Method and device for indication of quantizer parameters in video encoding system

FIELD: engineering of systems for encoding digital video signals, in particular, indication of values of quantization parameters in video encoding system.

SUBSTANCE: method and device for encoding a digital video series are claimed, where indication of quantization parameter is given out in encoded bit stream for use during decoding. Indication of information concerning the quantization parameter is ensured by insertion of SQP value - series level quantization parameter value. In particular, instead of encoding absolute values of parameters of quantization of image/section, indication of difference ΔQP between series level quantization parameter SQP and QP of image/section, is given out.

EFFECT: increased efficiency when encoding digital video signals and reduced speed of data transmission in bits.

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This application is based on provisional application for U.S. patent No. 60/374667, filed April 23, 2002, and this application claims the priority of the specified application.

The technical field to which the invention relates

The present invention relates to a method, encoder, decoder and device for encoding digital video signals. In particular, the invention relates to specify values of quantization parameters (QP) in video encoding.

Prior art

Digital video sequences recorded in the same way as kinosobytiem contain a sequence of still images, the illusion of motion is created by view images one after the other, usually with a frequency of 15-30 frames per second.

Each frame of uncompressed digital video sequence contains an array of image pixels. The frame is widely used in digital video format, known as the common interchange format compressed video data with a reduced four times the resolution (QCIF), contains an array of 176×144 pixels (i.e. 25344 pixels). Each pixel, in turn, presents a certain number of bits, which contain information about the brightness and/or color of the image area corresponding to the pixel. In the General case, to represent a brightness and color composition of the images, use the so-called YUV model. Luminance component or Y is (subjective) image brightness, and color composition of an image is represented by two components of chrominance or color difference components, denoted by U and V

Color model based on the representation of the brightness and color composition of the image, provide certain advantages compared to color models, which are based on the representation using the primary colors (i.e. red, green and blue, i.e., the RGB system). System human vision is more sensitive to rate changes than to changes in color, and YUV color model uses this property by appointment spatial resolution for chrominance components (U, V) is lower than for luminance (Y). Thus, the amount of information necessary to encode color information, can be reduced at an acceptable image quality degradation.

The spatial resolution of the chrominance components is usually lowered by means of subdirectly. Each frame of the sequence is usually divided into so-called "macroblocks", which contain the luminance (Y) information and appropriate color (U, V) information, which is subjected to spatial subdirectory.

Figure 1 shows on the in way, through which you can form a macroblock. Figure 1 shows the frame of the video sequence using the YUV color model, all components have the same spatial resolution. Macroblocks form a representation of the field of 16×16 pixels of the image into four blocks of luminance information, each luminance block contains an array of 8×8 luminance (Y) values and two spatially corresponding chrominance components (U and V), which exposes subdirectly by a factor of two both horizontally and vertically, and end up with an array of 8×8 values of chrominance (U, V). In accordance with some recommendations for coding, for example, recommendation H.26L of the telecommunication sector of the International telecommunication Union (ITU-T), the block size in the composition of the macroblocks may vary from 8×8, for example, may be 4×8 or 4×4 (see T. Wiegand, "Joint Model Number 1", Doc. JVT-A003, Joint Video Team (JVT) of ISO/IEC MPEG and ITU-T VCEG, Jan. 2002, Sections 2.2 and 2.3 (document JVT-A003 joint group of experts on data processing (JVT) on the basis of the expert group on cinematography (MPEG) under ISO/IEC and the expert group on coding (VCEG) in ITU-T, January 2002, sections 2.2 and 2.3). Recommendation H.26L (ITU-T also allows the joint organization of the macroblocks in the so-called "sections". Namely, each section of the Fort is irout of several consecutive macroblocks in the order of encoding and encode so, that section can be decoded independently, without consideration of any other section of the same scene. The advantage of this scheme lies in the ability to limit the spread of the distortion in the decoded video data, which may occur due to transmission errors. Despite the fact that there is no specific limitation on the method of potential development section, there is one simple scheme, the essence of which is that all the macroblocks in a single horizontal row of the frame group as a section. This scheme, together with the split image format QCIF at macroblocks 16×16 shown in figure 2.

As can be seen from figure 2, the image format QCIF contains 11×9 macroblocks (in this case, broken into groups of 9 sections, each of which contains 11 consecutive macroblocks). If luminance blocks and blocks of color are represented with 8-bit resolution (i.e. numbers in the range 0-255), then one macroblock required in the sum (16×16×8)+2×(8×8×8)=3072 bits. Therefore, the number of bits required to represent the video frame in the QCIF format is 99×3072=304128 bit. This means that the amount of information necessary to transmit/record/display the uncompressed sequence in QCIF format, presented using the YUV color model, 30 frames per second exceeds 9 M the it/s (million bits per second). The specified data rate is too high and practically not suitable for recording, transmission and display of video data, since it requires the storage capacity (memory), the bandwidth of the transmit channel and the performance of the hardware had a super value.

If the video you want to transfer in real time over the network with fixed communication lines, such as ISDN (digital network integrated services) or conventional PSTN (public switched telephone network public use), the available bandwidth when the data transfer is usually around 64 kbit/S. In mobile video telephony, when the transfer is at least partly carried by the radio link, the available bandwidth may be reduced up to 20 kbit/S. that is, that digital video can be sent over a narrow-band communication networks require significantly reduce the amount of information used to represent video data. For this reason, methods have been developed for video compression, which reduces the amount of transmitted information while maintaining acceptable image quality.

Methods of video compression is based on the reduction of redundant and useless for the perception of parts videopokeronline is Inesta. Redundancy in video sequences can be classified into spatial, temporal and spectral. The term "spatial redundancy" is used to describe the correlation (similarity) between neighboring pixels in the frame. The term "temporal redundancy" reflects the likelihood that objects that appear in one frame of the sequence, will appear in subsequent frames, and the term "spectral redundancy" refers to the correlation between different components of the color of the same image.

The pixels that make up each frame of the digital video sequence, often characterized by a high degree of mutual correlation, in other words, any pixel in the frame sequence has the same value as the other pixels in its immediate vicinity. System coding usually reduce spatial redundancy using the method known as block encoding conversion", according to which the blocks of pixels of the image process by a mathematical transformation, such as discrete cosine transform (DCT). This video is converted from a view containing the pixel values, in a form containing a set of values of coefficients of the spaces of the NGO-frequency components. Described an alternative representation of video data provides a significant reduction of spatial redundancy and thus a more compact representation of the video data.

Belonging to the video sequence frames, which are compressed using block coding with transform independently of any other frame in the sequence, called nutribase coded (INTRA-coded or I-hadrami.

The system of coding is usually not only reduce spatial redundancy, but also use a method called "prediction with motion compensation to reduce temporal redundancy in the sequence. When using prediction with motion compensation, the image contents of some (often many) frames of digital video sequences "predict" the content, at least one of the other frames of the sequence, called the "reference" frames. The image content cannot be predicted by tracking the movement of objects or areas of the image in the interval(s) between the encoded (compressed) by the frame and reference(s) frame(s) using "motion vectors". As in the case of INTRA-coding, the prediction video frame with motion compensation is usually performed on macroblocks.

Frames videopokeronline the tee, compressed using prediction with motion compensation, usually called miblock coded (INTER-coded) or predicted frames (P-frames). Only one prediction with motion compensation rarely provides a reasonably accurate representation of the image content of the frame, therefore it is usually necessary to provide a so-called frame "prediction errors" (PE-frame) with each INTER-coded frame. The frame of the prediction error is the difference between a decoded version of the INTER-coded frame and the contents of the encoded frame. In particular, the frame of the prediction error contains values that represent the difference between the pixel values in the frame to be encoded and the corresponding restored values of the pixels formed on the basis of the predicted variation on this frame. Therefore, the frame of the prediction error has characteristics similar to the static image, therefore, to reduce spatial redundancy and, consequently, the amount of information (number of bits)required to represent it, you can use block coding with transform.

Below the operation of a system of coding detail demonstrated by the example in figure 3 and 4. Figure 3 is a principle block diagram of a generalized video encoder to the second combines INTRA-coding and INTER-coding with the aim of creating a bitstream compressed (encoded) video. The corresponding decoder is depicted in figure 4, and the description of the decoder shown later in the text.

The video encoder 100 includes an input 101 for receiving the digital video signal from a camera or other video source (not shown). The video encoder also includes a module 104 conversion, which is designed to perform the block discrete cosine transform (DCT), a quantizer 106, an inverse quantizer 108, the module 110 inverse transform 110 that is designed to perform a reverse block discrete cosine transform (IDCT), combiners 112 and 116 and the storage 120 of the frame. In addition, the encoder contains the module 130 analysis of motion parameters, the encoder 140 motion and module 150 prediction with motion compensation. The switches 102 and 114 operate in a coordinated manner with control from the control module 160 to switch the encoder mode is INTRA-coding mode is INTER-coding and Vice versa. The encoder 100 also includes a multiplex coder 170 video, which forms one bit stream from different types of information generated by the encoder 100, for subsequent transmission to a remote receiving terminal or, for example, is deposited on the storage medium of large capacity, for example, on the computer's hard disk (not shown).

The encoder 100 operates as follows. Each frame of uncompressed video signal coming from the source video signal input 101, is received and processed by macroblocks, in the preferred embodiment, in the order of raster scanning. When you begin coding a new video sequence, the first encoded frame is encoded as INTRA-coded frame. Then the encoder is programmed for encoding each frame in the format of INTER-coding, until either of the following conditions: 1) the analysis shows that encode the current macroblock of the frame to be so different on the values of the pixels from the reference frame used for prediction, which is given information about too much of the forecast error, and then the current macroblock is encoded in the format of an INTRA-coding; 2) over a specified interval following INTRA-coded frames; or 3) from the receiving terminal has received the signal feedback request frame transmission in the format of an INTRA-coding.

Below is a description of the operation of the encoder 100 in the mode of INTRA-coding. In the INTRA mode coding, the control module 160 converts the switch 102 in position for receiving the input signal from the input line 118. The input signal is accepted by the macroblocks, and blocks of luminance values and color values that make up each macroblock are transmitted to the module 104 conversion, performing DCT (DCT module-conversion). This module will is b 2-black the discrete cosine transform, and generates for each block in the 2-dimensional array of coefficients of the discrete cosine transform (DCT coefficients).

DCT-coefficients for each block are passed to the quantizer 106, in which they quanthouse using the quantization parameter QP. The selection control of the quantization parameter QP performs the control module 160 on the control line 115.

In particular, the quantization of the DCT coefficients is performed by dividing the value of each coefficient by the quantization parameter QP and rounding the result to the nearest whole number. At the output of the quantization process produces many of the values of the quantized DCT coefficients, which are characterized by a lower numerical accuracy compared with the values of the coefficients initially generated by module 104 DCT transform. Therefore, in the General case, each of the quantized DCT coefficients can be represented by fewer information bits than required to represent the corresponding coefficient before quantization. In addition, the quantization process results in some DCT-coefficients to zero and thereby reduces the number of coefficients that you want to encode. The result of both of these processes reduce the amount of information (i.e. the number of information bits required to represent the DCT coefficients of the block image. Therefore, quantization provides an additional mechanism by which you can reduce the volume of the m information required to represent each image in the sequence. In addition, quantization introduces an irreversible loss of information, resulting in a corresponding reduction in image quality. Although the above-described image quality degradation may not always be desirable, the quantization values of the DCT-coefficients enables correction of the number of bits required to encode the video sequence with the purpose of, for example, considering the bandwidth available for transmission of the coded sequence or the desired quality of the encoded video data. In particular, by increasing the values of the QP used for the quantization of the DCT coefficients, it is possible to create lower quality, but more compact representation of video sequences. On the contrary, by reducing the values of QP, it is possible to form the coded bit streams of higher quality, but with less compression.

The quantized DCT-coefficients for each block are transferred from the quantizer 106 in multiplex coder 170 video data, as shown by line 125 to 1. Multiplex coder 170 video arranges quantized transform coefficients for each block using the procedure zigzag scan, and thereby converts the two-dimensional array of quantized values is the second of the transform coefficients in the one-dimensional array. Next multiplex coder 170 video data typically represents each non-zero quantized coefficient in the composition of a one-dimensional array by a pair of values, calledlevel(level) and the series (run)wherelevelgives the value of the quantized coefficient, and the series is a number of consecutive coefficients with zero values prior to this factor. Value series andleveladditionally compress statistical coding. For example, it is possible to apply this method, as uneven coding (VLC)to form a variety of combinations of variable length, which characterizes each pair of(series, level).

At the end of the statistical encoding of pairs(series, level)(for example, codes of variable length) multiplex coder 170 video then combines these pairs with control information, also statistically coded, for example, with the use of this method, non-uniform coding, which is suitable for information of this type to form a single compressed bit stream of encoded video data 135. It is specified bitstream containing the coded combinations of variable length, characterizing pairs(series, level)and the control information is associated, inter alia, the quantization parameter, QP, used the bathroom for the quantization of the DCT coefficients, sent from the encoder.

In the encoder 100 is formed also locally decoded version of the macroblock. This operation is performed by transmission of the quantized transform coefficients for each block generated by the quantizer 106, through the inverse quantizer 108 and performing inverse DCT transformation module 110 inverse transformation. Inverse quantization is performed by treatment of quantization performed by the quantizer 106. In particular, the inverse quantizer 108 tries to restore the original values of the DCT coefficients for the block of the image by multiplying each quantized values of the DCT-coefficient by the quantization parameter QP. Because of the rounding operation performed in the process of quantization by the quantizer 106, as a rule, it is impossible to restore the original values of the DCT coefficients. As a result, there is a difference between the recovered values of the DCT-coefficients and initially generated by module 104 DCT-transformation (and, hence, the aforementioned irreversible loss of information).

The operations performed by the inverse quantizer 108 and the module 110 inverse transformation, form the reconstructed array of pixel values for each block of the macroblock. The resulting decoded video data inputted in the multiplexer 112. In the mode of INTRA-Cody who Finance the switch 114 is set in such a position, to the input signal supplied to the multiplexer 112 through switch 114, consistent with zero. When this operation is performed by the unifier 112, equivalent to the transmission of the decoded video data without modification.

As subsequent macroblocks of the current frame are received and processed in accordance with the above-described stages of encoding and local decoding modules 104, 106, 108, 110 and 112, is formed decoded variant INTRA-coded frame in the storage 120 of the frame. After INTRA-encoded and then decoded the last macroblock of the current frame, the storage 120 of the frame contains the fully decoded frame, which can be used as a reference frame prediction when encoding the next received frame in the INTER-coded format. A flag that indicates the format of the INTRA-coding or INTER-coding is given in line 122.

Below is a description of the operation of the encoder 100 in the mode of INTER-coding. In the INTER mode coding, the control module 160 converts the switch 102 in position for receiving its input signal from line 117, which contains the output signal of the combiner 116. A multiplexer 116 receives the input video macroblock from input 101. As a multiplexer 116 receives blocks of brightness and color that make up the macroblock, the volume of inital forms corresponding data blocks of prediction errors. These prediction errors reflect the difference occurring between the observed block and its prediction and defined by the module 150 prediction with motion compensation. In particular, the data of the prediction error for each block of the macroblock contain a two-dimensional array of values, each of which represents the difference between the pixel value in the block of the encoded luminance or color information and the decoded value of the pixel obtained by the formation of the block prediction with motion compensation in accordance with the following procedure.

The data of the prediction error for each block of the macroblock are transmitted to the module 104 DCT transform, which performs two-dimensional discrete cosine transform for each block of values of the prediction error to generate a two-dimensional array of DCT coefficients of the transform for each block.

Transform coefficients for each block of the prediction error is transmitted to the quantizer 106, in which they quanthouse using the quantization parameter QP in the same way as described above in connection with the operation of the encoder mode is INTRA-coding. And again, the selection control of the quantization parameter QP performs the control module 160 on the control line 115. The accuracy of coding the prediction error can skorrektiroval the depending on the available bandwidth and/or the desired quality of the encoded video data. In a typical system with a discrete cosine transform (DCT) the specified operation is performed by changing the quantization parameter (QP)used in the quantization of the DCT coefficients with a given accuracy.

The quantized DCT-coefficients representing the data of the prediction error for each block in the macroblock is transmitted from the quantizer 106 in multiplex coder 170 video data, as shown by line 125 to 1. Similarly, the mode is INTRA-coding multiplex coder 170 video arranges the transform coefficients for each block of the prediction error using the procedure zigzag scan, and then represents each non-zero quantized coefficient in the form of pairs(series, level). The above advanced encoder compresses a pair of(series, level)using statistical coding, similarly as described above in connection with the mode of INTRA-coding. In addition, multiplex coder 170 video receives the data of the motion vector (description follows) of the encoder 140 motion along the line 126 and the control information (for example, indicating the quantization parameter QP from the control module 160. The specified encoder statistically encodes data of the motion vector and the control information, and generates a single bit stream of encoded video data 135, stereoselectivities the coded data of the motion vector and the prediction error and statistically encoded control information. Specifying, qz, the quantization parameter QP is transmitted in multiplex coder 170 video on line 124.

The quantized DCT-coefficients representing the data of the prediction error for each block in the macroblock are transmitted from the quantizer 106 in the inverse quantizer 108. Here they are processed by the method of the inverse quantization in the same way as described above in connection with the operation of the encoder mode is INTRA-coding. In the INTER mode coding, the quality of the encoded video bit stream and the number of bits required to represent a video sequence, can be adjusted by changing the degree of quantization to DCT coefficients representing data of the prediction error.

The resulting blocks is inversely quantized DCT coefficients are fed into the module 110 inverse DCT transformation, where are the inverse DCT-transformation for the formation of the locally decoded blocks of the values of the prediction errors. Then locally decoded blocks of the values of the prediction errors are introduced in the unifier 112. In the INTER mode coding, the switch 114 is set in such a position that the unifier 112 there were also predicted pixel values for each block in the macroblock, formed in the module 150 prediction with motion compensation. The unifier 112 combines each of the local the but the decoded blocks of the values of the prediction errors with the corresponding predicted block of pixel values to form the restored block image and enters them in the storage 120 of the frame.

As subsequent macroblocks of the video taken from the video source and processed in accordance with the above-described stages of encoding and decoding in the modules 104, 106, 108, 110, 112 is formed decoded version of the frame in the storage 120 of the frame. After processed the last macroblock of the frame store 120 frame contains the fully decoded frame, which can be used as a reference frame prediction when encoding the next received frame in the INTER-encoded format.

The following describes the process of forming a prediction for the macroblock of the current frame. Any frame encoded in the format of INTER-coding, needs a reference frame for prediction with motion compensation. This certainly means that, when encoding a video sequence, the first encoded frame, no matter whether the first is a frame sequence, or any other frame should be coded in the format of an INTRA-coding. This,in turn, it follows that, when the control module 160 switches the video encoder 100 in the INTER mode coding, the reference frame generated by the local decoding a previously encoded frame, already entirely exist in the repository 120 frame encoder. In General, the reference frame formed by local decoding or INTRA-coded frame or INTER-coded frame is.

The first stage of forming a prediction for the macroblock of the current frame is performed in the module 130 analysis of motion parameters. The module 130 analysis of motion parameters takes blocks of brightness and color that make up the current macroblock of the frame to be coded, on the line 128. Then the specified module performs the matching operation blocks, to detect the reference frame region, which essentially matches the current macroblock. To perform the matching operation blocks, the analysis module motion parameters accesses data of the reference frame stored in the storage 120 of the frame on line 127. In particular, the module 130 analysis of motion parameters performs mapping units calculating differential values (for example, sums of absolute differences), reflecting the differences between the pixel values of the analyzed macroblock and the corresponding values at possible options for optimally matching regions of pixels from the reference frame stored in the storage 120 of the frame. A differential value is calculated for possible areas in all possible positions within a given search area of the reference frame, and the module 130 analysis of motion parameters determines the minimum of the calculated differential value. The displacement between the macroblock of the current frame and an option unit the values of the pixels of the reference frame, at the point above the minimum differential value, determines a motion vector for the macroblock.

After the module 130 analysis of motion parameters generates a motion vector for a macroblock, this module generates the motion vector in the module 140 coding region of motion. The module 140 coding region of the movement approximates the motion vector obtained from the module 130 analysis of motion parameters, using motion models containing many basis functions and coefficients movement. In particular, the module 140 coding region of motion is a motion vector in the form of a set of values of coefficients of the movement, which when multiplied by the basis functions form an approximate representation of the motion vector. Usually use the translational motion model with only two factors of movement and basic functions, but you can use more complex motion models.

The coefficients of the motion is transmitted from module 140 coding region of motion in the module 150 prediction with motion compensation. The module 150 prediction with motion compensation also takes optimally matching variant region of the pixel values found by the module 130 analysis of motion parameters in the storage 120 of the frame. When using the approximate representation of vecto the and motion, generated by the module 140 coding region movement, and the pixel values of the optimal matching possible choices field of the reference frame, the module 150 prediction with motion compensation generates an array of predicted pixel values for each block of the macroblock. Each block of predicted pixel value is passed to a multiplexer 116, which subtracts the predicted pixel values of the actual (input) values of the pixels of the corresponding block of the current macroblock and thus generates a lot of blocks with errors of prediction for the macroblock.

Below is a description of the operation of the video decoder 200 shown in figure 4. The decoder 200 includes a multiplex decoder 270 video, which takes a bit stream of encoded video data 135 from the encoder 100 and demuxes mentioned stream into its component parts, the inverse quantizer 210, module 220 inverse DCT transformation, the module 240 prediction with motion compensation, the storage 250 of the frame, a multiplexer 230, the control module 260 and the output 280.

The control module 260 controls the operation of the decoder 200, depending on whether the decoded INTRA-coded or INTER-coded frame. The control signal mode INTRA-/INTER-coding, which instructs the decoder to switch from one mode Dec is tiravanija in the other, displayed, for example, of the type information of the image associated with each compressed video frame received from the encoder. The control signal mode INTRA-/INTER-coding stands out from the bit stream of encoded video multiplex decoder 270 video data and transmitted to the control module 260 of the control line 215.

INTRA-coded frame is decoded according to the macroblocks. Multiplex decoder 270 separates video data coded information related to the blocks of the macroblock, from the possible control information relating to a given macroblock. Encoded data for each block is INTRA-coded macroblock contains a combination of variable length, representing unevenly coded (VLC) values ofleveland the series is non-zero quantized DCT coefficients of the block. Multiplex decoder 270 decodes video data code combinations of variable length using the method of decoding variable length fields, corresponding to the encoding method used in the encoder 100, and thereby restores pairs(series, level). Then the decoder restores the array of quantized values of the transform coefficients for each block of the macroblock, and passes the above-mentioned values in the inverse quantizer 210. Any control information, kasaysayan the macroblock, also decoded multiplexed decoder 270 video data using the corresponding method of decoding and transmitted to the control module 260. In particular, information concerning the level of quantization of the transform coefficients (i.e., the quantization parameter QP), stands out from the encoded bitstream multiplex decoder 270 video data and transmitted to the control module 260 of the control line 217. The control module, in turn, transmits this information to the inverse quantizer 210 on the control line 218. The inverse quantizer 210 performs inverse quantization of the quantized DCT coefficients for each block of the macroblock in accordance with control information related to the quantization parameter QP, and issues already back quantized DCT-coefficients in the module 220 inverse DCT transform. The operation of the inverse quantization performed by the inverse quantizer 210, identical to the operations performed by the inverse quantizer 108 in the encoder.

Module 220 inverse DCT transform performs the inverse DCT transformation is inversely quantized DCT coefficients for each block of the macroblock to form a decoded block of video data containing the recovered pixel values. The restored values of the pixels are transferred through the multiplexer 230 to the output 280 of the video decode is a, with which, for example, they may be transferred to a display (not shown). The restored pixel values for each block in the macroblock are store 250 frame. Prediction with motion compensation is not applied when encoding/decoding the INTRA-coded macroblocks, so in this case, the control module 260 instructs the multiplexer 230 to transmit each block of pixel values without changing the output 280 of video data and store 250 frame. As are decoded and entered into the memory of the subsequent macroblocks INTRA-coded frame store 250 frame gradually linked decoded frame that is available for use as a reference frame for prediction with motion compensation in connection with the decoding of the received subsequently INTER-coded frames.

INTER-coded frames are also decoded by macroblocks. Multiplex decoder 270 video takes the bitstream 135 coded video data and separates the encoded data of the prediction error for each block is INTER-coded macroblock from the encoded data of the motion vector and the possible control information related to the considered macroblock. In accordance with the foregoing, the encoded data of the prediction error for each block of the macroblock typically contain code which new combinations of variable length, representing the values ofleveland the series is non-zero quantized transform coefficients of the considered block of prediction errors. Multiplex decoder 270 decodes video data code combinations of variable length using the method of decoding variable length fields, corresponding to the encoding method used in the encoder 100, and thereby restores pairs(series, level). Then the decoder restores the array of quantized values of the transform coefficients for each block of the prediction error and transmits these values to the inverse quantizer 210. Control information relating to INTER-coded macroblock, is also decoded in the multiplex decoder 270 video data using the corresponding method of decoding and transmitted to the control module 260. Information concerning the level of quantization (QP) of the transform coefficients of the blocks of prediction errors, stands out from the encoded bit stream and transmitted to the control module 260 of the control line 217. The control module, in turn, transmits this information to the inverse quantizer 210 on the control line 218. The inverse quantizer 210 performs inverse quantization of the quantized DCT coefficients representing the data of the prediction error for each block of the Mac is oblaka, in accordance with control information related to the quantization parameter QP, and issues already back quantized DCT-coefficients in the module 220 inverse DCT transform. Again, the operation of the inverse quantization performed by the inverse quantizer 210, identical to the operations performed by the inverse quantizer 108 in the encoder. The mode flag INTRA/INTER issued in line 215.

Then in the module 220 inverse DCT transform is the inverse transform is inversely quantized DCT coefficients representing the data of the prediction error for each block to obtain an array of reconstructed values of prediction errors for each block of the macroblock.

Multiplex decoder 270 video highlights from the bit stream 135 coded video data and decodes the coded data of the motion vector associated with the macroblock. Thus obtained decoded data of the motion vector are transmitted over control line 225 in module 240 prediction with motion compensation, which restores the motion vector for the macroblock using the motion models that were used to encode the INTER-coded macroblock, the encoder 100. The restored motion vector is an approximate representation of the motion vector, originally defined by the module 130 estimates the motion parameters of the encoder Module 240 prediction with motion compensation decoder uses the restored motion vector to determine the location of the restored pixels in the reference frame prediction, stored in the storage 250 of the frame. The pixel area specified by the restored motion vector is used to form a prediction for the macroblock. In particular, the module 240 prediction with motion compensation generates an array of pixel values for each block in the macroblock by copying the corresponding values of the pixels of the pixel area specified in the reference frame. These blocks of pixel values determined by the control frame transmitted from module 240 prediction with motion compensation in a combiner 230, where they are combined with the decoded data of the prediction error. In practice, the pixel values of each of the predicted block are added to the corresponding restored values of the prediction errors generated by the module 220 inverse DCT transform. So get an array of reconstructed pixel values for each block of the macroblock. The restored values of the pixels are transferred to the output 280 of a video decoder, and are entered in the storage 250 of the frame.

As are decoded and entered into the memory of the subsequent macroblocks of the INTER-coded frame store 250 frame gradually linked decoded frame that is available for use as a reference frame for prediction compensation magic cube MOV is I other INTER-coded frames.

In accordance with the foregoing, a typical system of coding and decoding (usually called codecs) operate on the principle of prediction with motion prediction and coding of prediction errors. Prediction with motion compensation is performed through the analysis and coding of motion from frame to frame and restore segments the image using the data movement. Encoding the prediction error is used to encode the differences between segments of the image with motion compensated and the corresponding segments of the original image. The accuracy of coding the prediction error can be corrected depending on the available bandwidth and the required quality of the encoded video data. In a typical system with a discrete cosine transform (DCT) the specified operation is performed by changing the quantization parameter (QP)used in the quantization of the DCT coefficients with a given accuracy.

It should be noted that in order to remain in sync with the encoder, the decoder must know the exact value of the QP used in coded video sequences. Usually dispatched one QP value for the section that leads to an increase in the number of bits which must be transmitted to the image encoding. (In accordance with the foregoing which, section contains part of the image and is encoded independently of other sections, to eliminate the spread of possible transmission errors in the image). For example, if the encoding of a single value QP requires 6 bits, and each second passed 20 images, each of which is divided into 10 sections, to transfer only information QP is required to 1.2 kbit/s

In accordance with known solutions (e.g., on the recommendation H.26L on the coding presented in the document: T. Wiegand, "Joint Model Number 1", Doc. JVT-A003, Joint Video Team (JVT) of ISO/IEC MPEG and ITU-T VCEG, Jan. 2002), the parameters QP images/partitions are encoded independently uniform or nonuniform code. These decisions lead to an increase in the bit rate in accordance with the above description. In particular, in accordance with the joint model No. 1 (Joint Model Number 1) on the recommendation H.26L, the value of the quantization parameter (QP)used for quantization values of the DCT coefficients, usually indicated in the coded bit stream at the beginning of each image (see T. Wiegand, "Joint Model Number 1", Doc. JVT-A003, Joint Video Team (JVT) of ISO/IEC MPEG and ITU-T VCEG, Jan. 2002, Section 3.3.1). If the macroblocks of the frame are organized in sections, then at the beginning of each section of the frame (for example, additional constituting the header section of the part of the encoded bit stream) also specifies the value of QP. In both cases QP indicated no change or encoded using an appropriate schema uneven coding. In accordance with the foregoing, it should be understood that this scheme is very costly in terms of the number of bits required to represent the data of the quantization parameter, especially if the frames are divided into many sections, and/or the bandwidth available for transmission of coded video sequences, is narrow. This problem is of particular complexity in the tasks associated with the transmission of video signals to mobile phones when the bit streams of encoded video data is passed through radio. In these circumstances, the bandwidth available for transmission of the bitstream of encoded video data may limit the transmission rate up to 20 kbit/s, and data QP entered in the bit stream, can occupy a significant portion of the entire available bandwidth.

In addition, in accordance with H.26L, the value of QP can be further modified at the level of the macroblock using the method consists in the fact that part of the encoded bitstream enter setting switching quantizer (Dquant)characterizing the considered macroblock (see T. Wiegand, "Joint Model Number 1", Doc. JVT-A003, Joint Video Team (JVT) of ISO/TEC MPEG and ITU-T VCEG, Jan. 2002, Section 3.4.7). This solution leads to a further increase in the volume of such information in the coded bit stream, which is used to specify information related to QP.

In view of the above, you should realize that there is a great need for an improved mechanism for specifying information concerning the values of quantization parameters, systems of video encoding.

A brief formulation of the invention

In accordance with the present invention, the known solutions for the instructions associated with the QP information improved input QP sequence level. In this application, the encoder may decide on the application of the reference QP-dependent sequence, to encode parameters QP images/partitions. Then, in accordance with the present invention, instead of encoding the absolute values of the parameters QP images/partitions enough to encode the difference between the QP of the reference sequence and actually used QP images/partitions. In accordance with this decision the full value of QP for each image/partition to convey not necessarily, but to restore the QP images/sections transfer and use statistically smaller differential value, which reduces the speed of data transmission in bits.

Reduced requirements for speed of data transmission in bits is most obvious at constant QP. Thus it is enough to send only one bit per cell to indicate that decoding CE is the use QP sequence. For example, in the previous example, the data transmission rate in bits for transmission QP is reduced from 1.2 kbit/s to 0.2 kbit/s (i.e. you want to send only one bit instead of six bits in each partition).

In accordance with the first aspect of the present invention proposes a method of encoding a digital video sequence, intended for use in the application of coding to form a bit stream of encoded video data representing a digital video sequence. Digital video sequence contains a certain number of frames, and each frame of the sequence contains an array of pixels divided into a set of blocks, and each block contains a certain number of pixels. The method comprises the stages consisting in the fact that encode a frame of the digital video sequence by applying the prediction with motion compensation to blocks of pixels and thereby form the respective blocks of the values of the prediction errors. Apply to blocks of values of the error encoding method with conversion to form sets of values of transform coefficients representing the units of the values of the prediction errors, and apply some level to the sets of values of transform coefficients to form a quantized set C is achene conversion factors. In accordance with the present invention, the method further comprises a step consisting in the fact that specify the default level of quantization to be applied during the whole process of encoding a digital video sequence, to quantize the set of values of transform coefficients.

The advantage is that the method in accordance with the first aspect of the present invention is also used to specify the values of the quantization parameter (QP)used in the quantization of the set of values of transform coefficients representing the blocks of pixel values generated for frames encoded in the INTRA mode coding, in the manner similar to that described above, to specify the values of the quantization parameter used to quantize the sets of values of transform coefficients representing the values of the prediction errors generated for frames encoded in the INTER mode encoding.

Preferably the default level of quantization to be applied during the whole process of encoding a digital video sequence is specific for the encoded video sequence. According to another option, the default level of quantization is specific to the application of videokameru the deposits.

In accordance with the preferred option given specifying the default level of quantization to be applied during the whole process of encoding a digital video sequence. In a more preferred embodiment, specifying the default level of quantization is given in the encoded bit stream representing the digital video sequence. Preferably, the encoded bit stream indicating the default level of quantization to be applied during the whole process of encoding a digital video sequence, is passed into the device videodatabase.

The advantage is that the default level of quantization to be applied during the whole process of encoding a digital video sequence in order to quantize the set of values of transform coefficients can be adjusted in the process of encoding a digital video sequence, when this issue other indication representing adjusted the default level of quantization.

In accordance with the preferred option specifying adjusted the default level of quantization is passed to the device videodatabase in the coded bit stream representing the digital videopokeronline the .

The advantage is that the level of quantization applied to the sets of values of transform coefficients may be adjusted so that the actual level of quantization applied to the sets of values of transform coefficients, different from the default level of quantization to be applied during the whole process of encoding a digital video sequence. In the preferred embodiment, used the actual level of quantization is introduced as the difference with respect to the default level of quantization. The advantage is that an indication of the difference with respect to the default level of quantization is given in the encoded bit stream representing the digital sequence.

In the embodiment, the video encoding method in accordance with the first aspect of the present invention, the level of quantization applied to the sets of values of transform coefficients may be adjusted from frame to frame of the digital video sequence in such a way that the actual level of quantization applied to the sets of transform coefficients for a particular frame of a digital video sequence that differs from the default level of quantization to apply the entire process of encoding a digital video sequence. The advantage is that in the present embodiment, the actual level of quantization for a particular frame are as a difference in relation to the default level of quantization, and an indication of the difference with respect to the default level of quantization is given in the encoded bit stream representing the digital sequence.

In another embodiment, the video encoding method in accordance with the first aspect of the present invention, the set of blocks into which the broken frame of the digital video sequence, group, at least one segment, and the level of quantization applied to the sets of values of transform coefficients may be adjusted from the segment-frame segment of the frame so that the actual level of quantization applied to the sets of transform coefficients for a particular segment of the frame is different from the default level of quantization to be applied during the whole process of encoding a digital video sequence. The advantage is that in accordance with this other embodiment, the actual level of quantization to be applied on a particular segment is represented as a difference in relation to taking what the reception is the default level of quantization and give an indication of the difference with respect to the default level of quantization in the encoded bit stream, representing the digital sequence.

The advantage is that if the default level of quantization is to be used for quantization of all sets of values of conversion factors across the digital video sequence, specifying the default level of quantization is given together with an indication that mentioned the default level should be used for quantization of all sets of values of transform coefficients for the entire digital video sequences.

In accordance with the second aspect of the present invention proposes a method of decoding encoded digital video sequence, intended for use in the application videodatabase to form a decoded digital video sequences. Mentioned digital video sequence contains a certain number of frames, and each frame of the sequence contains an array of pixels divided into a set of blocks, where each block contains a certain number of pixels and frames of the digital video sequence is coded by applying to the pixel blocks of the prediction with motion compensation to form the corresponding blocks of the values of the prediction errors, apply to b is the approx value of the prediction error coding method conversion to form sets of values of transform coefficients, representing the units of the values of the prediction errors, and the application of some level of quantization to the sets of values of transform coefficients to form a set of quantized values of the transform coefficients representing mentioned blocks of the values of the prediction errors. In accordance with the present invention a method of decoding includes a step consisting in the fact that specify the default level of inverse quantization to be applied during the whole process of decoding encoded digital video sequence, to perform the inverse quantization of the sets of quantized values of the transform coefficients.

The advantage is that the default level of inverse quantization is identical to the default level of quantization is used to quantize the sets of values of transform coefficients in the coding sequence.

Preferably, the default level of inverse quantization that is specified for use during the entire process of decoding encoded digital video sequence is specific to the decoded coded video sequences. In accordance with another embodiment the default level obratno the quantization is specific to the application videodatabase.

The advantage is that the method of decoding includes a step consisting in that restore specifying the default level of inverse quantization, in the preferred embodiment, the bit stream representing the encoded video sequence.

The advantage is that the default level of inverse quantization can be adjusted in the process of decoding a digital video sequence. In a preferred embodiment, the correction of the default level of inverse quantization is performed in dependence on the adjusted specify the default level of quantization used to encode the video sequences recovered from the bit stream representing the encoded digital video sequence. In accordance with another embodiment, the default level of inverse quantization is adjusted depending on the adjusted specify the default level of quantization used in the encoding of the video transmitted from the video encoding device.

The advantage is that the level of inverse quantization applied to the sets of quantized values of the transform coefficients, it is possible to adjust the thus, the the actual level of inverse quantization applied to the sets of quantized values of the transform coefficients, different from the default level of inverse quantization to be applied during the whole process of decoding encoded digital video sequence. In this case, the actual level of inverse quantization is determined by adding the differential value to the default level of inverse quantization, while the difference value represents the difference between the default level of inverse quantization and used the actual level of inverse quantization. In a preferred embodiment, the indication of differential values recovered from the bit stream representing the encoded digital video sequence.

In the embodiment, the method videodatabase in accordance with the second aspect of the present invention the level of inverse quantization applied to the sets of quantized values of the transform coefficients, adjusted from frame to frame of the digital video sequence in such a way that the actual level of inverse quantization applied to the sets of quantized transform coefficients for a particular frame of the digital video sequence, which differentiates itself here from the default level of inverse quantization to be applied during the whole process of decoding encoded digital video sequence. The advantage is that in this embodiment, the actual level of inverse quantization for use in a particular frame is determined by adding the differential value that is specific to the frame to accept the default level of inverse quantization, when this difference is specific to the frame, is the difference between the default level of inverse quantization and the actual level of inverse quantization for use in a particular frame. In a preferred embodiment, the indication mentioned differential values that are specific to frame, recovered from the bit stream representing the encoded digital video sequence.

In another embodiment of the method of videodatabase in accordance with the second aspect of the present invention a set of blocks that has a frame mentioned digital video sequence, group, at least one segment, and the level of inverse quantization applied to the sets of quantized values of the transform coefficients, correct from the segment-frame segment of the frame so that the actual level of inverse quantization applied to the sets of quantized transform coefficients in a particular segment of the frame is different from when imagelogo default level of inverse quantization to be applied during the whole process of decoding encoded digital video sequence. The advantage is that in this other embodiment, the actual level of inverse quantization for use in a particular segment is determined by adding the differential value, specific for a segment, the default level of inverse quantization, when this difference is specific to the segment represents the difference between the default level of inverse quantization and the actual level of inverse quantization for use in a particular segment. In a preferred embodiment, the indication mentioned differential values that are specific to the segment recovered from the bit stream representing the encoded digital video sequence.

In accordance with a third aspect of the present invention features an encoder for encoding a digital video sequence to form a bit stream of encoded video data representing a digital video sequence that contains a certain number of frames, and each frame of the sequence contains an array of pixels divided into a set of blocks, and each block contains a certain number of pixels. The video encoder in accordance with a third aspect of the present invention is configured to encode digital frame as the sequence through the use of prediction with motion compensation to blocks of pixels, in forming the respective blocks of the values of the prediction errors. The video encoder is additionally configured to apply to the blocks of the values of the prediction error coding method conversion to form sets of values of transform coefficients representing mentioned blocks of the values of the prediction errors, and the possibility of applying to the said sets of values of transform coefficients of a certain level of quantization to form a set of quantized values of the transform coefficients. In accordance with the present invention, the video encoder is additionally performed with an option to set the default level of quantization to be applied during the whole process of encoding a digital video sequence with the purpose of quantization sets of values of transform coefficients.

The advantage is that the encoder in accordance with a third aspect of the present invention is also made with the possibility of specifying the values of the quantization parameter (QP)used to quantize the sets of values of transform coefficients representing the blocks of pixel values generated for frames encoded in the INTRA mode coding, in the same way as described above, to specify the values of the quantization parameter, the IP is risovannyh for quantization of sets of values of transform coefficients, represent the values of prediction errors for frames encoded in the INTER mode encoding.

The advantage is that the default level of quantization is set by the decoder, is specific for the encoded video sequence.

The advantage is that the video decoder is additionally made with the possibility of issuing specify the default level of quantization in the encoded bit stream representing the digital video sequence. Preferably, the video decoder is configured to transmit the encoded bit stream into a corresponding video decoder.

The advantage is that the video decoder can be optionally configured to adjust the default level of quantization in the encoding process of the digital video sequence and outputting adjusted specify the default level of quantization. In a preferred embodiment, the encoder is also configured to instruct adjusted the default level of quantization in the corresponding video decoder. The advantage is that the encoder includes an indication of the adjusted default level of quantization in the encoded bit stream representing the digital videoposledovatel the awn.

In accordance with the preferred encoder is additionally made with the possibility of adjusting the level of quantization applied to the sets of values of transform coefficients, and thereby to apply the actual level of quantization, which is different from the default level of quantization. In a preferred embodiment, the video encoder is additionally configured to represent the actual level of quantization as a difference with respect to the default level of quantization and issuing instructions of a difference compared to the default level in the coded bit stream representing the digital sequence.

In one of the embodiments in accordance with the third aspect of the present invention, the video encoder is configured to adjust a level of quantization applied to the sets of values of transform coefficients from frame to frame of the digital video sequence. When the video encoder is configured to apply to the sets of transform coefficients for a particular frame of the actual level of quantization, which is different from the default level of quantization to be applied during the whole process of encoding a digital video sequence. Becoming the PTO is what the video encoder, in accordance with the present embodiment, it is additionally made with the possibility of representing the actual level of quantization for use in a particular frame as a difference with respect to the default level of quantization and the possibility of issuing instructions to the difference with respect to the default level of quantization in the encoded bit stream representing the digital sequence.

In another embodiment, in accordance with a third aspect of the present invention, the video encoder is additionally made with the possibility of grouping together blocks into which the broken frame of the digital video sequence, at least one segment and with the option of adjusting the level of quantization applied to the sets of values of transform coefficients, from segment to segment of the frame. When the video encoder is configured to apply to the sets of transform coefficients for a particular segment of the frame of the actual level of quantization, which is different from the default level of quantization to be applied during the whole process of encoding a digital video sequence. The advantage is that the video encoder in accordance with said another embodiment d is further configured to represent the actual level of quantization for use in a particular segment as a difference in relation to the default level of quantization and opportunity issuing instructions to the difference in relation to the default level of quantization in the encoded bit stream representing the digital sequence.

In a particular embodiment, the video encoder is configured to issue instructions to the default level of quantization and specify that the default level should be used for quantization of all sets of values of transform coefficients for the entire digital video sequences.

The advantage is that the video encoder in accordance with a third aspect of the present invention placed in a multimedia terminal. In a more preferred embodiment, the video encoder is implemented in the radio communications device.

In accordance with the fourth aspect of the present invention is proposed a decoder for decoding encoded digital video sequence to form a decoded digital video sequences. The digital sequence contains a certain number of frames, and each frame of the sequence contains an array of pixels divided into a set of blocks, each block contains a certain number of pixels and frames of the digital video sequence is coded by applying to the pixel blocks of prediction-compensated DV is the position to form the corresponding blocks of the values of the prediction errors, by applying for the units of the values of the prediction error coding method conversion to form sets of values of transform coefficients representing mentioned blocks of the values of the prediction errors, and by applying to the set of values of transform coefficients of a certain level of quantization to form a set of quantized values of the transform coefficients representing the units of the values of the prediction errors. In accordance with the present invention, the video decoder is configured to specify the default level of inverse quantization to be applied during the whole process of decoding encoded digital video sequence, to perform the inverse quantization of the sets of quantized values of the transform coefficients.

In accordance with the preferred option, the default level of inverse quantization is identical to the default level of quantization is used to quantize the sets of values of transform coefficients in the coding sequence.

The advantage is that the default level of inverse quantization that is specified for use during the entire process of decoding coded digital videopo is sledovatelnot, is specific to the decoded coded video sequences.

The advantage is that the video decoder is configured to recover specify the default level of inverse quantization, in the preferred embodiment, the bit stream representing the encoded digital video sequence.

The advantage is that the video decoder is configured to recover specify the default level of inverse quantization in the process of decoding a digital video sequence, in a preferred embodiment, by restoring the adjusted specify the default level of quantization of the bit stream representing the encoded digital video sequence. In accordance with another variant, the video decoder is configured to recover the adjusted specify the default level of quantization is transmitted from the video encoding device.

In accordance with the preferred option, the video decoder is configured to adjust a level of inverse quantization applied to the sets of quantized values of the transform coefficients, and applying the actual level of inverse quantization to the sets of quantized values to which fficient conversion, which is different from the default level of inverse quantization. The advantage is that the decoder is arranged to determine the actual level of inverse quantization by adding the differential value to the default level of inverse quantization, while the difference value represents the difference between the default level of inverse quantization and used the actual level of inverse quantization. In the preferred embodiment, video decoder configured to restore instructions differential values from the bit stream representing the encoded digital video sequence.

In one of the embodiments in accordance with the fourth aspect of the present invention, the video decoder is configured to adjust a level of inverse quantization applied to the sets of quantized values of the transform coefficients from frame to frame of the digital video sequence and the possibility of using the actual level of inverse quantization to the sets of quantized transform coefficients for a particular frame of the digital video sequence, the actual level of inverse quantization is different from the default level of inverse quantum is tion for use during the entire process of decoding encoded digital video sequence. The advantage is that the decoder is arranged to determine the actual level of inverse quantization for use in a particular frame by adding the differential value of the specific frame to the default level of inverse quantization, when this difference is specific to the frame, is the difference between the default level of inverse quantization and the actual level of inverse quantization for use on a specific frame. In a preferred embodiment, the video decoder configured to restore instructions differential values that are specific to the frame of the bit stream representing the encoded digital video sequence.

In another embodiment, in accordance with the fourth aspect of the present invention, the video decoder is configured to decode coded video sequences, in which a set of blocks that has a frame mentioned digital video sequences, grouped in at least one segment, and additionally made with the possibility of adjusting the level of inverse quantization applied to the sets of quantized values of the transform coefficients, from the segment-frame segment of the frame, and the applications of the actual level of inverse quantization to the sets of quantized transform coefficients for a particular segment of the frame, however, the actual level of inverse quantization is different from the default level of inverse quantization to be applied during the whole process of decoding encoded digital video sequence. In accordance with the preferred decoder is configured to determine the actual level of inverse quantization for use in a particular segment by adding the differential value of the specific segment to the default level of inverse quantization, when this difference is specific to the segment represents the difference between the default level of inverse quantization and the actual level of inverse quantization for use in a particular segment. In accordance with the preferred video decoder configured to restore instructions differential values specific to a segment of the bit stream representing the encoded digital video sequence.

In accordance with the fifth aspect of the present invention offers a multimedia terminal, containing the encoder in accordance with a third aspect of the present invention.

In accordance with the sixth aspect of the present invention offers a multimedia terminal, stereodecoder, in accordance with the fourth aspect of the present invention.

In accordance with a preferred embodiment of a multimedia terminal according to the fifth and/or sixth aspects of the present invention is a mobile multimedia terminal, configured to communicate with mobile telecommunication networks via radio connection.

List of figures

Figure 1 - formation of a macroblock of 16×16 in accordance with the prior art.

Figure 2 - podraznienie image in QCIF format at the macroblocks of 16×16 and the grouping of consecutive macroblocks in the partition.

Figure 3 - schematic block diagram of a generalized video encoder in accordance with the prior art.

Figure 4 - schematic block diagram of a generalized video decoder in accordance with the prior art and corresponding to the encoder shown in figure 3.

5 is a principal block diagram of a video encoder in accordance with the embodiment of the present invention.

6 is a principal block diagram of a decoder in accordance with the embodiment of the present invention and corresponding to the encoder shown in figure 5.

7 - the process of decoding in accordance with one possible implementation of this is part II of the invention, in which the quantization parameters (QP) for each partition is obtained by summing the quantization parameter sequence (SQP) with Delta QP values, specific sections (n).

Fig - schematic block diagram of a multimedia communication terminal, in which you can implement the method in accordance with the present invention.

Detailed description of the invention

In accordance with a preferred embodiment of the present invention, the quantization parameter (QP)that is specific for the sequence, transmit and use as a reference value when encoding and decoding the actual quantization parameters image/partition. It is not necessary to transfer the full value of QP for each image/partition, and transmit statistically smaller differential value, which is used to restore QP images/partitions that reduces the transmission speed in bits.

The following is a description of embodiments of the present invention with reference to figure 5-8.

Figure 5 presents a fundamental block diagram of the video encoder 600 in accordance with a preferred embodiment of the present invention. The scheme of the video encoder shown in figure 5 is essentially similar to the scheme of the known video encoder, p is shown in figure 3, however, it includes the relevant amendments to the constituent parts of the video encoder that performs operations associated with the quantization of the DCT coefficients of the transformation and transmission of signals with values of quantization parameter (QP)used in the process of coding. All components of the video encoder, which perform functions and actions are identical to the previously described known video encoder, denoted by identical positions. Because the present invention applies in particular to the transmission of signals with values of quantization parameter (QP) at the partition level or frame, in the following description, it is assumed that the video encoder 600 in accordance with a preferred embodiment of the present invention is intended, in particular, to apply this method of coding, in accordance with which the encoded frames of the video sequence is divided into macroblocks and then the macroblocks are grouped in sections, the quantization parameter is issued at the beginning of each frame and at the beginning of each new section in the frame. An example of this method of coding is given in the previously mentioned guidelines for coding ITU-T H.26L, the description of which is given in the document: T. Wiegand, "Joint Model Number 1", Doc. JVT-A003, Joint Video Team (JVT) of ISO/IEC MPEG and ITU-T VCEG, Jan. 2002. In accordance with another embodiment, the method can note the thread in such a system of coding, in which the indication of the quantization parameter is given only at the beginning of the frame. Although the following detailed description made with the specific purpose to show the application of the method in accordance with the present invention for solving the problem of specifying the parameters of the quantization level section and transmitting signals with the given parameters, it should be understood that the method can similarly be applied to the representation of the quantization parameters of the level frame (image).

Below is a detailed description of the principles of operation of the video encoder 600. When encoding a digital video sequence, the encoder 600 is similar to the encoder previously described in connection with figure 3, to form INTRA-coded and INTER-coded compressed video frames. As described above, in the INTRA mode coding, discrete cosine transformation (DCT) is performed for each block of video data (pixel values)to generate the corresponding two-dimensional array of values of transform coefficients. The DCT operation is performed in the module 104 conversion, and resulting from this activity coefficients are then transmitted to the quantizer 106, where they are quantization. In the INTER mode coding, the DCT transformation is performed in the module 104 refers to the units of the values of the prediction errors. Ratios are the options conversion formed as a result of this operation, is also transmitted to the quantizer 106 running also and their quantization.

In accordance with the present invention, at the beginning of the new coding of the video encoder 600 specifies the default or reference level quantization that should be applied during the whole process of quantization of video sequences for the quantization values of the DCT coefficients generated in the quantizer 106. In the following description referred to the default or reference level quantization is referred to as "quantization parameter level sequence" or, abbreviated, SQP. The selection control SQP for a given video sequence is performed by the control module 660 and, for example, this selection may be made based on the properties of the encoded sequence and the bandwidth available for transmission of the encoded bitstream generated by the encoder.

In accordance with a preferred embodiment of the invention, the encoder 600 sets SQP as the default or reference level of quantization for use in INTER mode coding, i.e. in circumstances where the DCT-coefficients generated in the module 104 conversion, represent the values of the prediction errors. It should be understood that the method in accordance with the present the invention can also be applied to the quantization values of the DCT coefficients, formed in normal mode INTRA-coding, which is not a prediction in the spatial domain. However, given the differences in the origin of the transform coefficients in the modes of INTRA-coding and INTER-coding (DCT-coefficients produced by INTRA-coding, calculated using the values of the pixels, and DCT-coefficients obtained in the INTER mode coding, calculated by DCT-transformation values of the prediction errors), it is hardly possible to determine a single value SQP, which would be optimal for the quantization of the DCT coefficients in the mode as the INTRA-coding and INTER-coding. Therefore, in the embodiment, in which the method in accordance with the present invention used in two modes : INTRA-coding and INTER-coding, it is advisable to use two values SQP, namely, one that provides the most effective presentation of information about the value of QP mode is INTRA-coding, and the other that provides the most effective representation of QP values in the mode of INTER-coding. In all other respects the method in accordance with the present invention can be applied quite similarly in both modes, i.e. INTRA-coding and INTER-coding. Of course, in accordance with another embodiment it is possible to determine a single value of the SQP and use the address as a parameter quantization level sequence for INTRA-coded, and for INTER-coded frames. This approach is practically feasible, especially in modern systems of coding, for example, in the system described in the document: T. Wiegand, "Joint Model Number 1", Doc. JVT-A003, Joint Video Team (JVT) of ISO/IEC MPEG and ITU-T VCEG, Jan. 2002, where the prediction in the spatial domain is used for INTRA-coded macroblocks before the error of the prediction mode is INTRA-coding is the coding using DCT.

It should additionally be noted that, since most typical frames of the video sequence is encoded as frames in INTER-format, the maximum decrease in the rate of data transmission in bits is achieved by application of the method in accordance with the present invention to the performance of the QP values in the mode of INTER-coding. Therefore, in accordance with the preferred embodiment of the present invention, use only one value SQP, which specifies the default or reference level of quantization for use in the quantization of the DCT coefficients representing the values of the prediction errors in the INTER mode encoding.

After determining the values of the SQP to be applied to the sequence control module 660 gives an indication of the selected value SQP on control line 122 in multiplex encoder 670 video data, which, in turn, inserts the decree is in the SQP values in the bit stream 635 coded video data, representing the sequence. In a preferred embodiment, the above-mentioned instruction is issued in constituting the title sequence fragment bit-stream 635 coded video data.

Then the video encoder 600 starts to encode the sequence. In accordance with the explanations given in connection with the description of known encoder 100, is shown in figure 3, the first frame of the encoded sequence is encoded in INTRA format. Since the SQP value, determined in accordance with the preferred embodiment of the present invention, is characteristic of the quantization values of the DCT coefficients generated in the INTER mode coding, the INTRA mode encoding operation of the encoder 600 is quite similar to the well-known video encoder 100 further optionally not described in detail.

After coding the first frame of the control module 660 switches the video encoder 600 in the INTER mode coding. In the INTER mode coding, the switch 102 operates to receive the input signal from line 117, in which there is an output signal of the combiner 116. A multiplexer 116 receives the macroblock input signal from input 101 and generates a data block of the prediction error for each block of the macroblock. The data of the prediction error for each block is transmitted in fashion is 104 DCT-transformation, which performs two-dimensional discrete cosine transform for each block of values of the prediction errors with the aim of forming a two-dimensional array of DCT coefficients transformations for this unit. Transform coefficients for each block of the prediction error is transferred to the quantizer 106, which quantum them in accordance with the foregoing by using a quantization parameter QP. Next, the process of INTER-coding continues in accordance with the above description with reference to well-known encoder 100.

As you receive each macroblock management module 660 determines whether the macroblock being processed at the moment, the first macroblock partition. If the macroblock is such, the control module determines the value of the quantization parameter QP for use in the quantization values of the DCT coefficients generated by the module 104 DCT transform. It should be noted that QP can be estimated on the basis of the number of bits allocated per frame, the number of bits already used in the previous sections of the frame, and possibly the number of bits spent on the section in the previous frame. Following the above assessment, the control module 660 determines the difference () between the previously determined value of the quantization parameter SQP sequence level and the actual the sky QP value to apply to this section. Then, the control module transmits an indication of this difference in the control line 624 in multiplex encoder 670 video, which further includes an indication of the difference in the bit stream 635. In the preferred embodiment, this indication is issued in constituting the header section of the fragment bit-stream 635 encoded video data that contains control information that is specific to the considered section. The described process is repeated until until all sections of the current frame will not be encoded by INTER-coding, then the video encoder immediately begins to encode the next frame of the sequence.

Below with reference to Fig.6 describes the decoder 700 in accordance with a preferred variant of the present invention. Scheme for the construction of the decoder shown in Fig.6, in essence, similar to the scheme of the known decoder, shown in figure 4, however, includes the relevant amendments to the constituent parts of the video encoder that performs operations related to the inverse quantization of the DCT coefficients of the transformation. All components of the decoder that perform functions and actions are identical to the previously described known to the decoder, denoted by identical positions.

In this description implies the tsya, what video decoder, shown in Fig.6, corresponds to the encoder described according to figure 5, and so made capable of receiving and decoding the bit-stream 635 transmitted by the encoder 600. As described above, the encoder 600 in accordance with a preferred embodiment of the present invention determines the quantization parameter SQP level sequence for use in the INTER mode coding. Accordingly, the decoder 700 is configured to receive to receive indications of the values of this SQP and using the quantization parameter SQP level of consistency in defining the parameters of the inverse quantization to be applied to blocks of the quantized values of the transform coefficients (representing the values of the prediction errors existing in the coded bit stream for INTER-coded frames. In accordance with another embodiment of the present invention is identical to the process can also be applied to quantized values of the transform coefficients recovered from the bit stream INTRA-coded frames. As follows from the above, in accordance with another embodiment it is possible to give an indication for two values of the SQP, one of which refers to the INTRA-coded frames of the sequence, and the other to the INTER-coded frames. In the accordance with one other embodiment, you can specify a single parameter quantization level sequence for frames encoded in two modes : INTRA-encoding and INTER-encoding.

Below is a detailed description of the principles of operation of the decoder in accordance with a preferred embodiment of the present invention. The decoder 700 receives the bitstream 635 and divides it into parts. This operation performs multiplex decoder 770 video.

At the beginning of the decoding of the new sequence, multiplex decoder 770 video first retrieves the information and settings associated with the entire sequence, comprising a sequence header of a fragment of the received bit stream 635. As follows from the above explanations with regard to the description of the encoder 600 in accordance with a preferred embodiment of the present invention, comprising a sequence header fragment bit stream is modified in such a way as to transmit the indication of the quantization parameter SQP level sequence used in the quantization values of the DCT coefficients generated in the INTER mode coding. Multiplex decoder video highlights the indication of the SQP values from the bit stream and, if this value is encoded, for example, by the method of Nera is numbered encoding, performs the corresponding decoding to recover the value of the SQP. Then multiplex the video decoder passes the value of the SQP in the control module 760 decoder, which enters this value in the memory of the decoder.

Then, the video decoder 700 begins to decode the coded frames of the video sequence, the decoding of each frame begins immediately after the video decoder starts to receive information relating to the frame in the bit stream 635 video. Multiplex decoder 770 video highlights the control signal mode INTRA-/INTER-coding of the information type of the video image associated with each compressed video frame taken in the coded bit stream 635, and transmits the above-mentioned signal to the control module 760 for control line 215. The control module 760 thus controls the operation of the decoder according to the control signal mode INTRA-/INTER-coding to switch the decoder to correctly decode mode.

In accordance with a preferred embodiment of the present invention for decoding the INTRA-coded frames is the same as described above in connection with the operation of the known decoder 200. On the other hand, decoding the INTER-coded frames is performed in accordance with h deprivement description.

When the control module 760 receives the indication selected from a received bitstream multiplex decoder 770 video, that the next decoded frame is INTER-coded frame, the control module 760 switches the decoder 700 in the INTER mode coding. As follows from the explanation with reference to the description of the encoder 600 in accordance with a preferred embodiment of the present invention, in which the macroblocks of each frame are grouped into sections, the encoded bit stream 635 contains certain specific sections of the control information, which indicates the values of QP-specific section, represented as the value of QP difference in respect to the quantization parameter SQP sequence level. The advantage is that the control information specific to each section, is given in the bit stream in the form constituting the segment header specific to the considered section. When you receive this fragment bitstream multiplex decoder video allocates the control information specific to the section, constituting the header section of a fragment of the bitstream, and passes the note to section recovered from the bit stream, the control module 760 for control line 717.

The module then upravleniya determines the level of inverse quantization to be applied to the quantized DCT-coefficients of the macroblocks in the section. This operation is performed by combining the values for the partition-specific sequence quantization parameter SQP adopted previously and stored in the memory of the decoder. In accordance with the above description, the operation of the inverse quantization performed in the decoder consists of multiplying each quantized DCT coefficient by an amount equal to the initially applied to the level of quantization, i.e. on the QP value used in the corresponding encoder for quantizing DCT coefficients. Therefore, in accordance with the preferred embodiment of the present invention, the control module 760 determines the level of the inverse quantizer for macroblocks section by summing the accepted value for the partition with SQP. Then, the control module transmits this value to the inverse quantizer 210 on the control line 218.

As encoded data for each macroblock partition is made in the bit-stream 635, multiplex decoder 770 video separates the encoded data of the prediction error for each block of the macroblock from the encoded data of the motion vector. The above-mentioned decoder restores the quantized DCT coefficients transformations, representing the values of the prediction error for each block, and passes them to the inverse quantizer 210. Then reverse the quantizer 210 performs inverse quantization of the quantized DCT coefficients in accordance with QP section, the restored values and SQP control module 760. Then the inverse quantizer passes back the quantized DCT-coefficients in the module 220 inverse DCT transform. The remaining part of the decoding process is performed in accordance with the description previously given in connection with the known decoder 200.

Stages of acceptance-specific partition values, combined with SQP and inverse quantization of the quantized DCT coefficients for each block of the macroblock in section repeat for each section of the frame, until decoding of all sections of the current INTER-coded frame. From this point on, the video decoder 700 begins decoding the next frame of the coded video sequences.

7 depicts a process in which specific sections of the QP values are restored in accordance with the preferred embodiment of the present invention. As can be seen from the figures, the process contains the following steps:

1. Is resetting the quantization parameter (SQP) sequence level;

2. You restore a differential quantization parameter (level image or partition;

3. Is the summation of the differential quantization parameters parameter quantization level sequence with the purpose of obtaining the quantization parameters for the image is of, or partition;

4. Restores coefficients encoding the prediction error using the quantization parameter of the image or partition.

On Fig presents terminal device containing hardware video encoding and videodatabase that can be used to perform operations in accordance with the present invention. More precisely, this figure shows a multimedia terminal 80 made in accordance with the recommendation H.324 Committee of the ITU-T. the Terminal can be considered as a multimedia transmission and receiving device. The terminal contains components that collect, encode and multiplexers streams of multimedia data for transmission over the communication network, as well as components that receive, demultiplexers, decode and display adopted multimedia information. Recommendation H.324 Committee of the ITU-T defines the General principles of operation of the terminal and contains links to other recommendations, which regulate the procedure for the operation of various component parts of the terminal. Multimedia terminal of the specified type can be used in such real-time applications, as duplex telephony, or not relevant to the real-time applications such as search and/or streaming video, for example, from a multimedia information server is on the Internet.

In connection with the present invention it should be understood that the terminal in accordance with the standard H.324 shown in Fig, represents only one of many possible variants of realization of the multimedia terminal, suitable for application of the method subject of the invention. It should also be noted that there are a large number of options associated with the placement and performance of the terminal equipment. As can be seen from Fig, multimedia terminal can be placed in the communication equipment connected to the telephone network with fixed line, for example, to the analog public switched telephone network (PSTN). In this case, the multimedia terminal includes a modem 91, the relevant recommendations V.8, V.34 and, optionally, V.8bis Committee of the ITU-T. In accordance with another variant of the multimedia terminal can be connected to an external modem. The modem allows you to convert the multiplexed digital data and control signals generated by the multimedia terminal, in analog form suitable for transmission over the PSTN. In addition, the modem allows the multimedia terminal to receive data and control signals in analog form from the PSTN network and convert them into a stream of digital data that the terminal can respectively demultiplex and clicks the process.

Multimedia terminal H.324 standard can also be performed so that it can be connected directly to a digital network with fixed communication lines, such as ISDN (digital network integrated services). In this case, the modem 91 replace interface user - network ISDN. On Fig specified interface user - network" ISDN presents an alternative module 92.

Multimedia terminals standard H.324 can also be performed in the variant for use in mobile applications. In case of use with a wireless communication line, the modem 91 can be replaced with any appropriate wireless interface, presents an alternative module 93 on Fig. For example, the multimedia terminal standard H.324/M can contain the radio transceiver, which allows you to connect to the mobile phone network modern 2nd generation GSM type or proposed network of the 3rd generation type UMTS (universal mobile telecommunications system).

It should be noted that in the scheme of multimedia terminals intended for duplex communication, i.e., for transmitting and receiving video data, it is expedient to provide both the video encoder and video decoder made in accordance with the present invention. Mentioned pair of encoder/decoder is often performed in the form of the aqueous the combined function module, called "codec".

Below is a detailed description of a typical multimedia terminal H.324 standard, with reference to Fig.

Multimedia terminal 80 includes a number of components, called "terminal equipment". This equipment includes video, audio and remote-control device, in General, is marked with the numbers 81, 82 and 83, respectively. Video 81 may contain, for example, a video camera for obtaining video monitor for displaying the received video information and equipment for optical processing of video information. Sound equipment 82 typically contains a microphone, for example, to retrieve voice messages, and sound system for reproducing a received audio information. Sound equipment may also contain additional blocks for processing audio information. Telecontrol equipment 83 may contain data entry terminal, keyboard, electronic tablet or transceiver static images, such as Fax.

Video 81 is connected to the codec 85. The codec 85 contains the video encoder 600 and a corresponding video decoder 700, each of which is made in accordance with the present invention (see figure 5 and 6). The codec 85 must encode the received video data in suitable the th format for subsequent transmission over the communication line and decoding compressed video information, adopted from a communication network. In the example shown in Fig, the video codec is made in accordance with recommendation ITU-T H.26L, with appropriate changes to implement the method in accordance with the present invention as in the encoder and in the decoder of the codec.

Sound equipment terminal is connected with the codec indicated on Fig position 86. Like video codec, audio codec contains a pair of encoder/decoder. The codec converts the audio data received audio equipment terminal in a format suitable for transmission over a communication channel, and converts the encoded audio data received from the network back into a format suitable for playback, for example, the acoustic system of the terminal. The output signal of the audio codec is passed to the delay module 87. This ensures that the latency compensation made by the process of coding, and therefore, the synchronization of audio and video information.

The system control module 84 multimedia terminal controls the alarm from the target device in the network using an appropriate control Protocol (signaling module 88)to establish a common mode of operation for transmitting and receiving terminals. Signal module 88 provides the exchange of information about the characteristics of the encoding and decoding transmitting the th and the receiving terminal, and may serve to support various encoding modes of the encoder. In addition, the system control module 84 controls the use of data encryption. Information regarding the type of encryption to use when transferring data sent from the encryption module 89 in the multiplexer/demultiplexer module (MUX/DMUX) 90.

When transferring data from the multimedia terminal, the module MUX/DMUX 90 combines the encoded and synchronized streams of video and audio data with the input data from the remote-control equipment 83 and possible control data, and thereby generates a single bit stream. Information regarding the type of encryption (if encryption is performed) for use in the bit stream issued by the cryptographic module 89, is used to select the encryption mode. Accordingly, when receiving multiplexed and possibly encoded multimedia bitstream, the module MUX/DMUX 90 must decrypt the bitstream, divide it by multimedia components and pass the elements to the corresponding(s) codec(s) and/or terminal equipment for decoding and playback.

If the multimedia terminal 80 is a mobile terminal, i.e. if the terminal is equipped with a radio transmitter and receiver 93, specialists in the art it is obvious that it may contain additional com is onesty. In accordance with one variant of implementation of the specified terminal includes a user interface comprising a display and a keyboard that allows the user to control the operation of the multimedia terminal 80, a CPU, for example, a microprocessor that controls the modules that are responsible for performing various functions of the multimedia terminal, operative memory (RAM), permanent memory (ROM) and digital video camera. Working command of the microprocessor, i.e., program code corresponding to the basic functions of the multimedia terminal 80 are stored in the permanent memory (ROM) and can be executed in accordance with the microprocessor, for example, under the control of the user. The microprocessor in accordance with the code uses the radio transceiver 93 for communication with the mobile network and thereby enables the multimedia terminal 80 to transmit information to and receive information from the mobile communication network by radio.

The microprocessor monitors the state of the user interface and controls the digital camera. In response to a user command, the microprocessor instructs the camera to capture a digital image in RAM. After or in the process of obtaining images of the microprocessor divides the image into image segments is based (for example, macroblocks) and uses an encoder for encoding segments with motion compensation to generate a compressed video sequence in accordance with the foregoing. The user can give a multimedia terminal 80 command to display the received image or the transmission of compressed video sequences using transceiver radios 93 in other multimedia terminal, a Videophone connected to a network with fixed line (PSTN) or any other telecommunication device. In a preferred embodiment, the video transmission begins immediately after encoding the first segment, so the recipient can start the process of decoding with minimum delay.

Above the present invention is described with reference to specific variants of implementation, however, specialists in the art of the obvious possibility of making many additions and modifications in the described in the examples. Therefore, although the present invention is shown and described in detail on the example of one or more preferred variants of its implementation, specialists in the art it is obvious that in the invention it is possible to make some additions or changes that do not go beyond either the defined limits and merits of the present invention.

In particular, in accordance with a second possible embodiment of the present invention, QP sequence is not passed, and instead of QP sequences use a constant that is specific for the sequence.

In accordance with a third possible embodiment of the present invention, QP sequence can be adjusted depending on the change characteristics of the video sequence, if there is a reliable way to transfer new QP sequence. The adjusted value of the SQP can either be included in the encoded bit stream representing a sequence, or can be directly transmitted from the encoder to the decoder in the corresponding control channel.

In accordance with a fourth possible embodiment of the present invention, if QP sequence has a constant value for the entire sequence, then pass only the value of QP sequence, stating that it should be used as a QP for all images/partitions.

1. A method of encoding a digital video sequence, intended for use in the application of coding to form a bit stream of encoded video data representing a digital video sequence, while digital is videoposledovatel contains a certain number of frames, each frame of said sequence contains an array of pixels divided into a set of blocks, each block contains a certain number of the above-mentioned pixels, and the above-mentioned method comprises the following steps, which encode a frame of the digital video sequence by applying the prediction with motion compensation to the blocks of pixels to form the corresponding blocks of the values of the prediction error; and applying to said blocks of values, the prediction error encoding method with transformation with the purpose of formation of the sets of values of transform coefficients representing mentioned blocks of the values of the prediction errors, while the above-mentioned encoding method differs in that it includes a stage on which to set the default level of quantization for use in the process of encoding a digital video sequence, to quantize the above set of values of transform coefficients.

2. The encoding method according to claim 1, characterized in that the said default level of quantization is specific for the encoded video sequence.

3. The encoding method according to claim 1, characterized in that the said default level of quantization is application-specific Videokamera the project.

4. The encoding method according to claim 1, characterized in that it further comprises a stage on which give an indication of the default level of quantization for the decoding process.

5. The encoding method according to claim 4, characterized in that the above-mentioned specifying the default level of quantization is given in the bit stream of encoded video data representing a digital sequence.

6. The encoding method according to claim 5, wherein the bitstream of encoded video data is passed from the video encoding device in the appropriate device videodatabase.

7. The encoding method according to claim 1, characterized in that the default level of quantization is adjusted in the process of encoding a digital video sequence, while the above-mentioned method further comprises a step, which give an indication of the adjusted default level of quantization for the decoding process.

8. The encoding method according to claim 1, characterized in that the said set of values of transform coefficients quantuum to form sets of quantized values of the transform coefficients representing mentioned units value error of the prediction, based on the level of quantization is different from the default level of quantization

9. The encoding method of claim 8, characterized in that it further comprises a stage on which the decoding process generates an indication of the difference between the level of quantization and the default level of quantization.

10. The encoding method of claim 8, characterized in that said level of quantization adjusted from frame to frame of the digital video sequence in such a way that the actual level of quantization applied to the sets of transform coefficients for a particular frame of a digital video sequence that differs from the default level of quantization.

11. The encoding method of claim 10, characterized in that the actual level of quantization can be represented as a difference in relation to the default level of quantization.

12. The encoding method of claim 10, characterized in that it further comprises a stage on which the decoding process generates an indication of the difference between the actual level of quantization and the default level of quantization.

13. The encoding method of claim 8, wherein the set of blocks of pixels, which has a frame mentioned digital video sequences, grouped into one or more segments, and the level of quantization applied to the sets of the values of transformation coefficients, correct from the segment-frame segment of the frame so that the actual level of quantization applied to the sets of transform coefficients for a particular segment of the frame is different from the default level of quantization.

14. The encoding method according to item 13, characterized in that it further comprises a stage on which the decoding process generates an indication of the difference between the level of quantization and the default level of quantization.

15. Video encoder for encoding a digital video sequence to form a bit stream of encoded video data representing a digital video sequence, the digital video sequence contains a certain number of frames, each frame of said sequence contains an array of pixels divided into a set of blocks, each block contains a certain number of the above-mentioned pixels, and the video encoder includes means for encoding a frame of the digital video sequence by applying the prediction with motion compensation to the blocks of pixels to form the corresponding blocks of the values of the prediction errors; means for converting the aforementioned blocks of the values of the prediction errors to form sets of zacharylaylat conversion, representing the above-mentioned units of the values of the prediction errors, while the above-mentioned encoder differs in that it includes means for selecting the default level of quantization, with the goal of quantization is referred to sets of values of transform coefficients.

16. The video encoder according to 15, characterized in that the said default level of quantization is specific for the encoded video sequence.

17. The video encoder according to 15, characterized in that it further comprises means for issuing instructions mentioned default level of quantization in the encoded bit stream representing the digital sequence.

18. The video encoder according to 15, characterized in that the said set of values of transform coefficients quanthouse to form sets of quantized values of the transform coefficients representing mentioned units value error of the prediction, based on the level of quantization is different from the default level of quantization.

19. Video encoder for p, characterized in that it further comprises means for issuing instructions to the difference between the level of quantization and the default level of quantization in the encoded bit stream.

20. The video encoder according to 15, otlichayushiesya, what is the default level of quantization can be adjusted, with the video encoder is configured to issue instructions adjusted the default level of quantization in the encoded bit stream.

21. The video encoder according to claim 20, characterized in that the said set of values of transform coefficients quantized to form the sets of quantized values of the transform coefficients representing mentioned units value error of the prediction, based on the level of quantization is different from the adjusted default level of quantization.

22. Video encoder for p, characterized in that said level of quantization applied to the sets of values of transform coefficients may be adjusted from frame to frame of the digital video sequence is thus to apply the actual level of quantization to said sets of transform coefficients for a particular frame of the digital video sequence, and the actual level of quantization is different from the default level of quantization.

23. The video encoder according to article 22, characterized in that it further comprises means for issuing instructions mentioned differences from the default level of quantization to the consolidated bit stream, representing the digital sequence.

24. Video encoder for p, characterized in that it further comprises means for grouping together blocks that are broken frame mentioned digital video sequence into one or more segments; a means for correcting the level of quantization applied to the sets of values of transform coefficients, from the segment of the frame to the segment frame thus to apply the actual level of quantization to said sets of transform coefficients for a particular segment of the frame, with said encoder is additionally distinguished by the fact that the actual level of quantization is different from the default level of quantization, and mentioned the video encoder is additionally configured to represent the actual level of quantization intended for use in a particular segment, as a difference with respect to the default level of quantization.

25. The video encoder according to paragraph 24, characterized in that it further comprises means for issuing instructions mentioned difference with respect to the default level of quantization in the encoded bit stream representing the digital sequence.

26. The video encoder according to 15, characterized in that available in the multimedia terminal.

27. The video encoder according to 15, characterized in that it is placed in the radio communications device.

28. The method of decoding encoded digital video sequence, intended for use in the application videodatabase to form a decoded digital video sequence, the digital video sequence contains a certain number of frames, each frame of said sequence contains an array of pixels divided into a set of blocks, each block contains a certain number of the above-mentioned pixels and frames of digital video sequences encoded by the way, according to which are applied to the pixel blocks of the prediction with motion compensation with the aim of forming values corresponding blocks of prediction errors; apply to those blocks of values, the prediction error encoding method with conversion to form sets of values of transform coefficients representing mentioned blocks values errors predictions; and apply the default level of quantization to the mentioned sets of values of transform coefficients to form a set of quantized values of the transform coefficients representing mentioned blocks of the values of the prediction errors, thus indicating the aforementioned default level of quantization is given in the encoded bit stream, containing encoded digital video sequence, and the aforementioned method of decoding differs in that it includes a stage on which to choose the level of inverse quantization for use in the process of decoding the encoded digital video sequence to perform inverse quantization mentioned sets of quantized values of the transform coefficients, while the mentioned level is chosen based on the guidelines mentioned above the default level of quantization, issued in the coded bit stream.

29. The method of decoding according p, characterized in that the said chosen level of inverse quantization is specific to the decoded coded video sequences.

30. The method of decoding according p, characterized in that the said chosen level of inverse quantization is specific to the application videodatabase.

31. The method of decoding according p, characterized in that it contains the phase in which mentioned the default level of quantization is adjusted in the process of the above-mentioned formation of the above-mentioned sets of quantized values of the transform coefficients, while the above-mentioned method of decoding differs in that it further comprises a stage on which adjust the selected level of education is tion quantization depending on the adjusted default level of quantization.

32. Video decoder for decoding the encoded digital video sequence to form a decoded digital video sequence, the digital video sequence contains a certain number of frames, each frame of said sequence contains an array of pixels divided into a set of blocks, each block contains a certain number of the above-mentioned pixels and frames of the digital video sequence is coded by applying to the pixel blocks of the prediction with motion compensation with the aim of forming values corresponding blocks of prediction errors; application to the mentioned blocks of values, the prediction error coding method conversion to form sets of values of transform coefficients representing mentioned blocks of values, the prediction error; and applying the default level of quantization to the above sets of values of transform coefficients to form a set of quantized values of the transform coefficients representing mentioned blocks values of prediction errors, and the indication referred to the default level of quantization is given in the encoded bit stream containing encoded digital video sequence, and amenity video decoder differs it contains a tool for restoring encoded digital video sequence from the encoded bit stream; and means for selecting the level of inverse quantization for use in the process of decoding the encoded digital video sequence in order to perform the inverse quantization of the mentioned sets of quantized values of the transform coefficients, while the mentioned level of inverse quantization is chosen based on the mentioned instructions mentioned default level of quantization, issued in the coded bit stream.

33. Video decoder on p, characterized in that the said chosen level of inverse quantization is specific to the decoded coded video sequences.

34. Video decoder on p, characterized in that the said default level of quantization is adjusted in the process of the above-mentioned formation of the above-mentioned sets of quantized values of the transform coefficients, while the said video decoder is configured to adjust a selected level of inverse quantization depending on the adjusted default level of quantization.

35. Video decoder on p, characterized in that available in the multimedia terminal.

36. Video decoder on p,characterized in that what is placed in the radio communications device.



 

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5 cl, 3 dwg

FIELD: method for interpolating values of sub-pixels during encoding and decoding of data.

SUBSTANCE: method of interpolation during video data encoding is claimed, which features an image, containing pixels ordered in rows and columns and represented by values having given dynamic range, where pixels in rows are in integral horizontal positions, and pixels in rows are in integral vertical positions, which image is interpolated in such a way that values of sub-pixels are generated in fractional horizontal and vertical positions, aforementioned method containing following stages: a) when values are required for sub-pixels in half-integral horizontal positions and integral vertical positions and in integral horizontal positions and half-integral vertical positions, such values are interpolated directly using weighted sums of pixels located in integral horizontal and integral vertical positions; b) when values are required for sub-pixels in half-integral horizontal positions and half-integral vertical positions, such values are interpolated directly using a weighted sum of values for sub-pixels located in half-integral horizontal positions and integral vertical positions, computed in accordance with stage a); and c), when values are required for sub-pixel in quaternary horizontal position and quaternary vertical position, such values are interpolated by averaging of at least one pair from first pair of values of sub-pixel located in half-integral horizontal position and half-integral vertical position, and of sub-pixel, located in integral horizontal position and integral vertical position, and second pair of values of pixel, located in integral horizontal position and integral vertical position, and of sub-pixel, located in semi-integral horizontal position and semi-integral vertical position.

EFFECT: creation of improved method for interpolating values of sub-pixels during encoding and decoding of data.

13 cl, 26 dwg, 2 tbl

FIELD: observation of moving objects.

SUBSTANCE: method includes using movement sensors, capable of recording two-dimensional distributions of intensity in form of images, where sensors are positioned with known spatial orientation, making it possible to perform simultaneous observation of one and the same scene, periodical query of sensors is performed during whole time period after their enabling, processing and analysis of data received from sensors is performed, which constitutes series of images, and output signal is generated in case of detection of three-dimensional moving object and determining of its spatial position, which signal is injected into output device.

EFFECT: increased trustworthiness when determining spatial position of a moving object.

3 cl, 1 dwg

FIELD: systems for automatic video surveillance of an object.

SUBSTANCE: system for automatic detection and tracking of individuals on basis of images and biometric identity recognition based on target list, realizes following operations: on basis of three-dimensional data about scene and two-dimensional data, characterizing optical flow, detection of objects-noises of scene is performed, static background objects are selected, and regular dynamic object-noises; on basis of comparison of two-dimensional and two-dimensional data about the scene in current frame with reference data on previous frames and a map of object-noises changes are determined on a scene, in three-dimensional zones of interest, preliminary check of presence of human-like objects is performed, zones of interest are determined more precisely and their changes are tracked: a contour of separate elements of human body is singled out, zones of interest are divided onto a set of sub-zones of interest for elements, detection of three-dimensional head of individual is performed and it is tracked in each zone of interest; face of individual is tracked in each zone of interest; images of detected face are normalized in terms of dimensions, angles and brightness; recognition is performed.

EFFECT: objectivity and stability of system operation.

1 dwg

FIELD: video encoding, in particular, methods and devices for ensuring improved encoding and/or prediction methods related to various types of video data.

SUBSTANCE: the method is claimed for usage during encoding of video data in video encoder, containing realization of solution for predicting space/time movement vector for at least one direct mode macro-block in B-image, and signaling of information of space/time movement vector prediction solution for at least one direct mode macro-block in the header, which includes header information for a set of macro-blocks in B-image, where signaling of aforementioned information of space/time movement vector prediction solution in the header transfers a space/time movement vector prediction solution into video decoder for at least one direct mode macro-block in B-image.

EFFECT: creation of improved encoding method, which is capable of supporting newest models and usage modes of bi-directional predictable (B) images in a series of video data with usage of spatial prediction or time distance.

2 cl, 17 dwg

FIELD: mobile robot, such as cleaner robot, and, in particular, device for tracking movement of mobile robot.

SUBSTANCE: suggested device for tracking movement of mobile robot includes: video camera for filming an individual object; unit for tracking movement and creation of image for setting support one in an image for current moment by means of filming of individual object by video camera and creation of image in current moment, for which support zone is set; unit for selecting image of difference of pixels of image support zone limit based on difference between pixels present only at limit of support zone of aforementioned images; and micro-computer for tracking movement of separate object on basis of selected image of difference.

EFFECT: decreased time of pixel comparison operation and increased efficiency of room perception.

5 cl, 4 dwg

FIELD: system for encoding moving image, in particular, method for determining movement vector being predicted, of image block in B-frame in process of decoding of moving image.

SUBSTANCE: in accordance to method, at least one movement vector is produced for at least one block, different from current block, while aforementioned at least one block is related to one, at least, supporting frame in a row of supporting frame, movement vector is predicted for current block on basis of received one, at least, movement vector, while prediction operation includes also operation of comparison of value of order number of B-frame to value of order number of one, at least, supporting frame, while movement vector for current block and aforementioned one, at least, movement vector are vectors of forward movement.

EFFECT: increased efficiency.

2 cl, 1 dwg

FIELD: technology for processing images of moving objects, possible use, in particular, in theatric art, show business when registration/recording is necessary or repeated reproduction of scenic performance.

SUBSTANCE: method includes inserting enumeration system for each object and performing projection of enumerated objects onto plane, while projection is displayed in form of graph with trajectories of movement of enumerated objects in each staging.

EFFECT: spatial-temporal serial graphic display of scenic action for its further identification and repeated reproduction.

2 dwg

FIELD: device and method for recognizing gestures in dynamics from a series of stereo frames.

SUBSTANCE: method includes producing a series of stereo-images of object, on basis of which map of differences in depths is formed. System is automatically initialized on basis of probability model of upper portion of body of object. Upper portion of body of object is modeled as three planes, representing body and arms of object and three gauss components, representing head and wrists of object. Tracking of movements of upper part of body is performed with utilization of probability model of upper part of body and extraction of three-dimensional signs of performed gestures.

EFFECT: simplified operation of system, high precision of gesture interpretation.

3 cl, 12 dwg

FIELD: movement detection systems, technical cybernetics, in particular, system and method for detecting static background in video series of images with moving objects of image foreground.

SUBSTANCE: method contains localization of moving objects in each frame and learning of background model with utilization of image remainder.

EFFECT: increased speed and reliability of background extraction from frames, with possible processing of random background changes and camera movements.

4 cl, 14 dwg

FIELD: television.

SUBSTANCE: support frame is assigned with sign, showing information about direction of support frame, and during determining of predicted vector of movement of encoded block averaging operation is performed with use of vectors of movement of neighboring blocks, during which, if one of aforementioned blocks has movement vectors, information about direction of support frames is received, to which these movement vectors are related, and one of movement vectors is selected with reference to received information about direction, than averaging operation is performed with use of selected movement vector to receive subject movement vector of encoded block.

EFFECT: higher precision, higher reliability.

3 cl, 1 dwg, 3 ex

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