Correction of video errors based on feedback communication line information

FIELD: information technologies.

SUBSTANCE: video data is coded, packet is formed with coded video data, and packet is transferred via wireless channel into access network. Level of access control to transfer medium (MAC) receives negative notice from the access network (NAK). It is identified whether received NAK is associated with packet, which contains video data. If received NAK is associated with packet, which contains video data, errors are corrected.

EFFECT: improved efficiency of video data errors correction.

36 cl, 5 dwg

 

This patent application is a partial continuation of the patent application from the applicant claims the priority of application No. 11/315399, filed December 21, 2005 and entitled "METHODS AND SYSTEMS FOR ADAPTIVE ENCODING OF REAL-TIME INFORMATION IN PACKET-SWTTCHED WIRELESS COMMUNICATION SYSTEMS" (case number in the registry attorney 051126), and which claimed priority to provisional application US No. 60/729017, filed October 21, 2005, the entire contents of which are incorporated herein by reference.

The technical field to which the invention relates

The present description relates to video encoding and, more specifically, to the lower level of the reverse link, facilitate error correction of the video.

The level of technology

Cell phone may include an audio capture device, such as a microphone or a speech synthesizer, and the audio encoding device for generating audio packets (or frames). The phone can use the levels of the communication Protocol and modules such as the module of the Protocol of the radio communication (RLP), the level of access control for transmission medium (MAC) and physical (PHY) layer. The phone can put the audio packets in the queue RLP. Module level MAC can generate the MAC level packets from the content queue RLP. The MAC level packets can be converted to the packet level PHY for transmission through the communication channel to another condition is the unit of communication.

Disclosure of invention

One aspect relates to a method containing the steps that encode video data; form a package of Internet Protocol (IP) with the encoded video data; transmit the packet across a wireless channel to the access network; receiving from the network access level access control for transmission medium (MAC) negative notice (NAK); determine whether associated adopted NAK with the package that contains video data; determine what IP packet contains data that has been lost during transmission; and performing error correction, if the received NAK is associated with a packet that contains video data.

Another aspect relates to a method containing the steps, which encode the first frame of video data; form a package with the encoded first frame of video data; transmit the packet across a wireless channel to the access network; determine, whether from the access network level access control for transmission medium (MAC) negative notice (NAK)before to encode a second frame of video data; determine whether associated NAK is received with a packet that contains video data; and then perform error correction, if the received NAK is associated with a packet that contains video data.

Another aspect relates to a device containing computer-readable memory that stores n the set of instructions, configured to encode video data; forming a package of Internet Protocol (IP) with the coded video data; send the packet through the wireless channel to the access network; to receive from the access network a negative notice (NAK) control access to the transmission medium (MAC); to determine whether associated adopted NAK with the package that contains video data; determine what IP packet contains data that has been lost in transmission; perform error correction, if the received NAK is associated with a packet that contains video data.

Another aspect relates to a device containing computer-readable memory that stores a set of instructions configured to encode the first frame of video data; forming a package with the encoded first frame of video data; send the packet through the wireless channel to the access network; determine, whether from the access network level access control for transmission medium (MAC) negative notice (NAK)before to encode a second frame of video data; determine whether associated adopted NAK with a packet that contains video data, and then perform error correction, if the received NAK is associated with a packet that contains video data.

Another aspect relates to the device containing the video encoder configured DL is in to encode video data; a module configured to generate a packet Internet Protocol (IP) with the coded video data; a transceiver configured to: (a) to transmit the access network packet through the wireless channel, and (b) to receive from the network access level access control for transmission medium (MAC) negative notice (NAK); a module configured to determine associated with whether adopted NAK with the package that contains video data, and to determine what IP packet contains data that has been lost in transfer; and if the received NAK is associated with a packet that contains video data, the video encoder is configured to perform error correction.

The device containing the video encoder configured to encode the first frame of video data; a first module configured to generate a packet with the encoded first frame of video data; a transceiver configured to: (a) to transmit the access network packet through the wireless channel, and (b) to receive from the network access level access control for transmission medium (MAC) negative notice (NAK); a second module configured to before to encode a second frame of video data to determine whether the level of the MAC from the network to blunt NAK, and to determine associated with whether adopted NAK with the package that contains video data; and a module error correction, configured to perform error correction, if the received NAK is associated with a packet that contains video data.

Details of one or more embodiments of the present invention set forth below in the accompanying drawings and description.

Brief description of drawings

Figure 1 - illustration of a communication system with a device for encoding video and audio, sending data through the transmission channel decoding device.

Figure 2 - illustration of the method and structures for the first method of detection and correction of errors, which can be used in the system illustrated in figure 1.

Figure 3 - illustration of a method and structure for the second method of detection and correction of errors, which can be used in the system illustrated in figure 1.

4 is a further illustration of the first and second methods, illustrated on figure 1 and figure 2.

Figure 5 - illustration of an example of detection of a lost packet and accelerate intraabdominal, which minimizes error propagation caused by a lost packet.

The implementation of the invention

The encoding and transmission of video and audio

Figure 1 - illustration of a system 10 communicate with the device 12, the video encoding and the dio, sending data through the channel 16 of the transfer (including component 15 network access device 14 decoding. The device 12 and encoding device 14 decoding can be distributed throughout the system 10. The device 12 and encoding device 14 decoding can represent different types of devices, such as wireless phone, cell phone, laptop, wireless multimedia device, wireless card of a personal computer (PC), pocket PC (PDA), an external or internal modem, or any device that communicates through a wireless channel.

And the device 12 coding, and the device 14 decoding can have different names, such as access terminal (AT), block access, subscriber unit, mobile station, mobile device, mobile unit, mobile phone, mobile, remote station, remote terminal, remote unit, user device, user equipment, handheld device, etc.

Each device 12, 14 can communicate with the component 15 of the access network (AN) in a straight line (FL) and/or the return line (RL). FL (downward line) corresponds to the transmission from AN 15 devices 12, 14. The reverse link (or ascending line) corresponds to the transmission device 12, 14 AN 15. AN 15 can the t match the network part of the communication system and may include (but not limit) or to implement the function of the base station (BS), two-way radio system base station (BTS), access point (AP), a modem pool transceiver (MPT), Node B (for example, in the system such as WCDMA), etc.

The device 12 coding may be present in the first device video and can include source 17 audio source 18 video, the video encoder 20, the audio encoder 22, a transport Protocol real-time (RTP)/Protocol user datagram (UDP)/module 26 convert an Internet Protocol (IP), all 28 of the Protocol of the radio communication (RLP), the module 30 MAC-level and module 32 physical layer (PHY). Other embodiments of the device 12, the encoding may include other elements instead of or in addition to the elements shown in figure 1. Other embodiments of the device 12, the encoding may include fewer elements than shown in figure 1.

The device 14 decoding may be located in another device, the video and can include a module 34 level PHY module 36 MAC-layer queue 38 RLP module 40 conversion RTP/UDP/IP video decoder 42, the audio decoder audio 44, block 46 audio output and the block 48 video output. Other embodiments of the decoding device 14 may include other elements instead of or in addition to the elements shown in figure 1. Other embodiments of the decoding device 14 may include includes fewer items as shown in figure 1.

Through the channel 16, the system 10 can provide bi-directional transmission of video and audio, such as video telephony (VT). Similar coding, decoding and conversion modules may be provided on opposite ends of the channel 16. In some embodiments, implementation of the present invention, the device 12 and encoding device 14 decoding can be implemented within the video devices, such as wireless mobile terminals equipped for video streaming, VT, or both. Mobile terminals can support VT in accordance with the standards of packet switching, such as RTP, UDP, or IP.

Source 18 video can be a device to capture video images, such as a video camera, one or more storyboards, or a combination of video cameras and video archives. Video encoder 20 generates encoded video data packets in accordance with the method of video compression, such as MPEG-4. Can be used in other methods of video compression, such as H.263 International telecommunications Union (ITU), ITU H.264, or MPEG-2. Video encoder 20 may provide a scheme for controlling the speed of the video source, which in most cases depends on the codec. For example, video encoder 20 may be configured to encode video in compliance with the MPEG4, H.63 ITU

or ITU H.264. Video encoder 20 may be implemented by a DSP or embedded logical kernel.

Source 17 audio can be an audio capture device, such as a microphone, or device a speech synthesizer. Audio encoder 22 may encode the audio data and generate packets of audio to accompany the video. Audio data may be encoded in accordance with the method of audio compression, such as adaptive multistrata narrow band (AMR-NB) or other techniques. With respect to VT video will allow you to see the participant VT conference, and audio will allow you to hear the voice of the speaker.

Module 26 conversion RTP/UDP/IP receives packets of video and audio data from video encoder 20 and audiocamera 22. Module 26 conversion RTP/UDP/IP can add the appropriate header information of the RTP/UDP/IP packets of audio and video data received from AudioCodes 22 and video encoder 20, and place the data packets in the queue 28 RLP. RTP can function at the top of UDP. UDP can operate on top of IP. In a specific configuration IP can function on the upper level Protocol transmission from point to point (PPP).

Module level 30 MAC can restore packages RLP queue 28 RLP and package level MAC. Each level pack for MAC can transfer the header information of the RTP/UDP/IP packet audio or video data, which are within the queue 28 RLP.

The audio packets can be inserted in the queue 28 RLP regardless of video packages. In some cases, the MAC-layer packet that is generated from the content queue 28 RLP, will transfer only the header information and the packet of video data. In other cases, the MAC-layer packet will transfer only the header information and the packet of the audio data. In other cases, the MAC-layer packet will move the header information, the packet of the audio data and the video package, depending on the content of the queue 28 RLP. The MAC level packets can be configured in accordance with the Protocol of the radio communication (RLP) and may be referred to as packet MAC RLP.

Module 32 level PHY can convert batches MAC RLP in the packet level PHY for transmission over the channel 16. Channel 16 transfers the packet level PHY device 14 decoding.

In the device 14 decoding module 34 PHY level and module 36 MAC level can work in a similar way. Module 34 level PHY can distinguish the MAC level packets from the packet level PHY and convert/rebuild packages PHY level taken from the channel 16 in the packet MAC RLP.

Module 36 level MAC can reflow the content packs MAC RLP to provide packets of video and audio to insert packets MAC RLP queue 38 RLP. Module 40 conversion RTP/UDP/IP can hide/remove the accompanying header information of the data in the queue 38 RLP and Paramonov the th video and audio data for delivery to the video decoder 42 and the audio decoder audio 44, respectively.

The video decoder 42 decodes frames of video data to generate video data stream for use in the device 48 display (output video). Audio decoder audio 44 decodes the audio data to generate audio data for presentation to the user, for example, through the speaker 46 (audio output device).

Video telephony (VT) corresponds to the real-time transmission of audio packets and video, among at least two devices, such as systems 12 and 14. With respect to VT mobile device VT (wireless terminal) receives the packet level PHY via wireless direct communication line (FL) (that is, "the descending line") from the base station. Device VT transmits the packet level PHY via wireless reverse communication line (RL) (i.e., "upward communication") to the base station.

The system 10 and the channel 16 can be configured to support one or more wireless technologies, such as multiple access, code division multiple access (CDMA)multiple access frequency division multiple access (FDMA), multiple access with time division multiplexing (TDMA)multiplexing orthogonal frequency division (OFDM) or other suitable wireless technique. The above wireless technology can be implemented in the CE is provided with any of a variety of radio access techniques. For example, CDMA can be implemented in accordance with the standards CDMA2000 or wideband CDMA (WCDMA). TDMA can be implemented in accordance with the standard global system for mobile communications (GSM). Standard universal mobile telecommunications system (UMTS) allows operation WCDMA or GSM. For applications VT system 10 may be performed with the opportunity to support technology standard high data rate (HDR)such as CDMA2000 1x EV-DO Revision 0, Version A or later EV-DO.

The channel state may be a small problem for wireless channels, but can be particularly problematic for mobile applications VT, in which the channel state may suffer from attenuation or network overload.

Error correction video

Using the lower-level methods of error correction video can address errors that occur with the video data for transmission on the reverse link. Methods may provide the ability to video encoder 20 may use information in the error channel from level 30 MAC and immediately apply error correction, without waiting for feedback from the receiving device 14. The methods may use mechanisms to retrieve/receive error information, which can be understood by the video encoder 20. Depending on the desired complexity of the information the Oia error from level 30 MAC can be converted in two different sizes.

After taking from the lower levels of error messages, video encoder 20 may: (a) to use for the new frame different reference frame, (b) increase the update rate of intramacrophage (MV) or (c) insert intrakat (key frame or I-frame)to stop error propagation in the receiver. Insert I-frame is essentially the same as the acceleration of intraabdominal. In the I-frame every MB intraction, i.e. does not depend on the previous frame that can stop error propagation. To update the intra-MV only a few MV intra-coded. Option (c) can be circumvented by using the duplicate I-frames (or decrease speed pack intricata) to improve coding efficiency and video delay time, and ensure the best video quality when errors occur. Video quality may improve as video encoder 20 may correct the error immediately instead of gradually upgrade each MB in the frame sequence.

Figure 5 - illustration of an example of detection of a lost packet and accelerate intraabdominal, which minimizes error propagation caused by a lost packet.

Below uses a reverse link CDMA2000 1x EV-DO Version A, as one example, receiving/retrieving error information from level 30 MAC. The methods can also be applied to other communication systems, such as the WCDMA system with high-speed packet access uplink communication (HSUPA), who use H-ARQ, NAK, or other similar method of detecting transmission errors and/or lost data.

The following methods can provide are performed at all levels optimized for the characteristics of the errors in terms of multimedia over wireless networks, including video telephony and video sharing, where transmission errors may be inevitable.

In respect of transmission errors in a straight line (downward line) some of the ways you can use end-to-end feedback to provide information about the error. However, if these methods rely solely on end-to-end feedback, they are unable to react quickly enough to a transmission error RL to reduce artifacts caused by lost packets. Described in this document how RL can complement method end-to-end feedback.

Error correction video with the MAC using the information NAK

This section describes two methods of error correction video with the MAC, which use negative information notice (NAK) from the network 15 access. In both video encoder 20 or module 206 error correction may request a level 30 MAC on a frame-by-frame basis, that is, before coding a new frame, video encoder 20 may receive error information from one or more lower levels, and E. what do you want, to perform error correction. Based on a message type of error information, video encoder 20 may implement different error correction circuits to suppress the propagation of errors.

First method: the error correction using the NAK packet IP video stream

Figure 2 - illustration of the method and structures for the first method, where the video encoder 20 or module 206 error correction are informed, what macroblocks (MB) in the video frame is lost during transmission. Each frame of video may contain a lot of macroblocks.

When there are transmission errors, network 15 access sends a NAK in the reverse channel traffic level 30 MAC (RTCMAC). Level 30 MAC informs the module 210 Protocol combining packages (PCP) on the MAC package associated with this NAC.

Module 210 PCP determines whether the lost packet MAC some data of the video stream. Audio and video can be placed in the same package MAC, even if the quality of service (QoS) is supported in the return line connection, EV-DO revision A. If a lost packet MAC is video data, the module 210 PCP by NAK RLP packet informs the module 208 RLP what the RLP queue (can be multiple queues RLP) contains the package in which errors have occurred during transmission.

Module 208 RLP determines the IP packet contains the lost data. Module 208 RLP has information about the IP packet. For EV-DO Version Is a video stream is configured so that to the data block of the stream lines of communication were IP service. Then by NAK IP packet flow module 208 RLP informs the application layer level 202 RTP which the IP packet was lost.

Level 202 RTP supports map or table, which converts the lost IP packet lost in the frame MV. Then information about the lost MV will be transferred to the module 206 error correction and/or video encoder 20 for further error correction.

This first method may include modifications in three different levels:

- Video encoder 20 transmits the level 202 RTP information MV in each package.

Level 202 RTP supports map or a conversion table between IP packets (indexed by the ordinal numbers) and the macroblock. If the IP packet is lost, the level of the RTP 202 can convert the IP packet into macroblocks and to inform the encoder about lost 20 MV. Associated with each IP packet sequence number can also be transferred to the module 208 RLP.

Module 208 RLP monitors how IP packets are fragmented into packets RLP, and by checking the sequence number determines the IP packet is lost.

For error correction, as video encoder 20 knows what MV is lost, the video encoder 20 or module 206 error correction may implement one or more of the following methods for correction of errors:

- Restrict the range of p is the claim estimation motion, that corrupted (lost) part is not used as the prediction.

- Interaktywna combined MV and their neighboring MB.

- The use of different reference frames for combined MV.

Second method: the error correction using NAK video stream

The above-described first method can provide good error-correcting capabilities and performance, but the complexity of the implementation can be relatively high. The first method may have the need to change the RTP and levels 202, 208 RLP. The second method can provide a simpler, but effective method of correcting errors.

Figure 3 - illustration of a method and structure for the second method. Compared illustrated in figure 2, Figure 3 may not require modification level 202 RTP. In fact, the second method may not need to perform any operations at level 202 RTP. Instead, the video encoder or module 206 error correction can make a request module 208 RLP to encode each new frame of video data, and the error information for error correction can be transferred directly to the video encoder 20 or module 206 error correction. This error message may simply be a flag (e.g., bit), installed in the module 208 RLP, which informs the video encoder 20, if you have lost some data in the video stream since the AK was made last request level 30 MAC. In one embodiment of the present invention the level 30 MAC can automatically send NAK module 210 PCP sends NAK module 208 RLP, which sets a flag without any queries levels 210 PCP or 30 MAC.

Between the encoding of the two video frames of the video encoder 20 may only be necessary to know whether any data is lost in the previous frame, thus, video encoder 20 or module 206 error correction may perform error correction on the current frame. Since the encoder 20 or the module 206 error correction requests module 208 RLP on a frame-by-frame basis, that is, before coding a new frame, knowledge, is there any error in transmission, can be as useful as the knowledge which the IP packet was lost.

If the MAC layer uses automatic repeat request (MARQ) for the video stream, this flag should be set only when containing video package MARQ is not acknowledged (ACK) is positive in the physical level.

This second method could simplify the implementation complexity and provide useful video encoder 20 information in order to perform proper error correction. However, since the flag can only point, was a mistake or not, video encoder 20 may not know which part of the frame is lost. Therefore, error correction must assume that the error there is in any part of any frame, since the last query.

As soon as this flag is set, the video encoder 20 may perform one or more of the following methods of error correction, which may differ from the first method:

- The encoding of the current frame as an I-frame.

- Increase in the percentage intracoronary MV.

- Can be used for motion estimation frame before the previous frame as a reference.

4 is a further illustration of the first and second method. Channel return line connection, EV-DO Version A is used as an example, but can be used with other types of channels, standards and communication protocols. As illustrated in the lower part of figure 4, level 30 MAC sends a packet with the MAC, containing audio and video data, the physical layer 32 in the form of the first subpackage in the time slot n. For example, at level 30 MAC can be 50 packet transmissions per second, assuming the 12th slot end, and all of these packages MAC transfer video data. The physical layer EV-DO can provide the ability to access terminal almost instantly detect a lost packet on the reverse link.

Level 30 MAC receives from the base station NAK through the channel hybrid ARQ (H-ARQ). Level 30 MAC tries to send the second subpackage during time slot n+3. Level 30 MAC receives from the base station a second NAK again through the channel H-ARQ. Level 30 MAC tries to send the third is the package during time slot n+6. Level 30 MAC receives from the base station a third NAK again through the channel H-ARQ. Level 30 MAC tries to send the fourth subpackage during time slot n+9. The MAC layer 30 receives from the base station NAK through the channel last ARQ (L-ARQ), and also receives from the base station NAK through the channel packet ARQ (P-ARQ). This triggers a level 30 MAC to inform the module 210 PCP.

The second approach can enable video encoder 20 to recover quickly after an error and the user may not notice the deterioration of video quality. The second method is to insert an I-frame immediately after an error, to immediately stop the propagation of errors. When there are no errors, through I-frames of the second method can provide better quality and fewer gaps in the frame than the other methods.

The device 12 video encoding may include dedicated memory to store instructions and data, as well as dedicated hardware, software, firmware or combinations thereof. If implemented in software tools, these techniques may be implemented as instructions on a machine-readable medium such as random access memory (RAM), a persistent storage device (ROM), nonvolatile random access memory (NVRAM), electrically erasable programmable post is permanent memory (EEPROM), flash memory, etc. Mentioned instruct one or more processors to perform specific aspects of the functionality disclosed in the present description.

Described in the present invention methods can be implemented in the framework of the universal microprocessor, digital signal processor (DSP), a specialized integrated circuit (ASIC), gate arrays, user-programmable (FPGA), or other equivalent logic devices. For example, the device 12, the video encoding device 14 decodes the video and associated components and modules may be implemented as part of the encoding process or the process of encoding/decoding (CODEC), running on a digital signal processor (DSP) or other processing device. Accordingly, the components are described as modules, can generate programmable features such process or a separate process.

The device 12 video encoding may include dedicated memory to store instructions and data, as well as dedicated hardware, software, firmware or combinations thereof. If implemented in software tools, these techniques may be implemented as instructions executed by one or more processors. Instructions mo is ut be stored on a machine-readable carrier, such as random access memory (RAM), a persistent storage device (ROM), nonvolatile random access memory (NVRAM), electrically erasable programmable permanent memory (EEPROM), flash memory, magnetic or optical storage device, etc. Mentioned instruct one or more processors to perform specific aspects of the functionality disclosed in the present description.

Described various embodiments of the present invention. These and other embodiments of the present invention are within the following claims.

1. The error correction method of the video containing the segments, which encode the video data; form a package of Internet Protocol (IP) with the coded video data; transmit the said package in the access network via the wireless channel; accept negative notice (NAK) from the network-level access control access to the transmission medium (MAC); determine associated with whether a received NAK with the package that contains video data; determine what IP packet contains data that has been lost during transmission; perform error correction, if the received NAK is associated with a packet that contains video data.

2. The method according to claim 1, wherein the package contains the macroblock is (MB) of video data, however, the above method further comprises a stage on which convey information about the macroblock from the video encoder on the transport Protocol real-time communication (RTP).

3. The method according to claim 1, additionally containing phases in which requests the MAC layer after encoding a frame of video data, but before encoding a new video frame to determine whether NAK MAC layer; and performing error correction, if the MAC layer has received the NAK.

4. The method according to claim 1, additionally containing a stage at which inform the Protocol module merge packets (PCP) about the received NAK.

5. The method according to claim 1, additionally containing a stage at which inform the Protocol module of the radio communication (RLP) about the received NAK, if the received NAK is associated with a packet that contains video data.

6. The method according to claim 5, additionally containing phase, which will determine whether the RLP queue contains the package in which errors have occurred during transmission.

7. The method according to claim 1, additionally containing a stage at which inform the application layer of the packet associated with the received NAK.

8. The method according to claim 1, further comprising stages that support map match between packets of the Internet Protocol IP and the macroblocks of video data; determine, using the map matching to convert the IP packet in acrobacy video frame, what macroblock has been lost during transmission, after determining whether the IP packet contains data that has been lost during transmission; perform error correction for macroblocks that were lost during the transfer.

9. The method according to claim 8, in which the error correction includes at least one of: (a) limiting the search range of motion estimation so that the damaged part is not used as prediction, (b) intracoronary combined macroblock and the neighboring macroblock, and (C) the use of different reference frames for the combined macroblocks.

10. The method according to claim 1, wherein the wireless channel includes a channel corresponding to the Version And CDMA2000 lx EV-DO (multiple access code division with the development of optimization data).

11. The method according to claim 1, wherein the wireless channel includes a channel wideband multiple access code division (WCDMA) high speed packet access uplink communication (HSUPA).

12. The error correction method of the video containing the segments, which encode the first frame of video data; form a package with the encoded first frame of video data; transmit the said package in the access network via the wireless channel; before encoding the second frame of video data, determine whether the level of access control to the rede transmission (MAC) negative notice (NAK) from the access network; determine associated with whether a received NAK with the package that contains video data; and performing error correction, if the received NAK is associated with a packet that contains video data.

13. The method according to item 12, in which at the stage of determining whether the level of access control for transmission medium (WT) negative notice (NAK) from the access network, check to see if the flag in the Protocol module of the radio communication (RLP).

14. The method according to item 12, optionally containing phase, which inform the application layer about the received NAK.

15. The method according to item 12, optionally containing phase, which inform the encoder about the received NAK.

16. The method according to item 12, further containing the step on which Protocol module of the radio communication (RLP) establish a one-bit flag indicating that the MAC layer has received the NAK.

17. The method according to item 12, in which the error correction includes at least one of: (a) encoding the second frame as an I-frame, (b) increase the percentage intracoronary macroblocks, and (C) the use of a frame before the first frame as a reference for motion estimation.

18. The computer-readable memory that stores a set of instructions configured to perform error correction of the video, and the instructions when executed cause the computer
to encode VI is dannye; to form the package of the Internet Protocol (IP) with the coded video data; send the packet through the wireless channel to the access network; to receive from the access network a negative notice (NAK) at the level of management access to the transmission medium (MAC); to determine associated with whether a received NAK with the package that contains video data; determine what IP packet contains data that is lost during transmission; and to perform error correction, if the received NAK is associated with a packet that contains video data.

19. The computer-readable memory p, and mentioned package contains macroblocks (MB) of video data, further containing instructions for sending information about macroblocks from the video encoder on the transport Protocol real-time communication (RTP).

20. The computer-readable memory p in which the instructions are additionally configured to request the MAC layer, after encoding a frame of video data, but before encoding a new video frame, to determine whether NAK MAC level; and to perform error correction, if the MAC layer has received the NAK.

21. The computer-readable memory p in which the instructions are additionally configured to inform the Protocol module merge packets (PCP) about the received NAK.

22. The computer-readable memory p in which instructions will complement the correctly configured for to inform the Protocol module of the radio communication (RLP) about the received NAK, if the received NAK is associated with a packet that contains video data.

23. The computer-readable memory according to article 22, in which the instructions are additionally configured to determine whether the RLP queue contains the package in which errors have occurred during transmission.

24. The computer-readable memory p in which the instructions are additionally configured to inform the application layer of the packet associated with the received NAK.

25. The computer-readable memory p in which the instructions are additionally configured to maintain a map of correspondence between packets of the Internet Protocol (IP) and the macroblocks of video data; after determining which IP packet contains data that has been lost during transmission, using the map matching for converting the IP packet into macroblocks of the video frame to determine which macroblocks are lost during transmission; and to perform error correction for macroblocks that were lost during the transfer.

26. The computer-readable memory A.25, in which the error correction includes at least one of: (a) limiting the search range of motion estimation so that the damaged part is not used as prediction, (b) interaktywna with the absorbed macroblock and the neighboring macroblock, and (C) the use of different reference frames for the combined macroblocks.

27. The computer-readable memory p, and wireless channel includes a channel corresponding to the Version And CDMA2000 lx EV-DO (multiple access code division with the development of optimization data).

28. The computer-readable memory p, and wireless channel includes a channel wideband multiple access code division multiple access (WCDMA) high speed packet access uplink communication (HSUPA).

29. The computer-readable memory that stores a set of instructions configured to perform error correction of the video, and the instructions when executed cause the computer to encode the first frame of video data; forming a package with the encoded first frame of video data; send the packet through the wireless channel to the access network; determine before encoding the second frame of video data, whether the level of access control for transmission medium (MAC) negative notice (NAK) from the access network; determine associated with whether a received NAK with the package that contains video data; and to perform error correction, if the received NAK is associated with a package contains video data.

30. The computer-readable memory according to clause 29, in which when determining whether the level of access control for transmission medium (MAC) negative notice (NAK) from the network access is a, check to see if the flag in the Protocol module of the radio communication (RLP).

31. The computer-readable memory according to clause 29, in which the instructions are additionally configured to inform the application layer about the received NAK.

32. The computer-readable memory according to clause 29, in which the instructions are additionally configured to inform the encoder about the received NAK.

33. The computer-readable memory according to clause 29, in which the instructions are additionally configured to set Protocol module of the radio communication (RLP) one-bit flag to indicate that the MAC layer has received the NAK.

34. The computer-readable memory according to clause 29, in which the error correction includes at least one of: (a) encoding the second frame as an I-frame, (b) increase the percentage intracoronary macroblocks, and (C) the use of a frame before the first frame as a reference for motion estimation.

35. A device for implementing error correction video containing a video encoder configured to encode video data; a module configured to generate a packet Internet Protocol with the coded video data; a transceiver configured to (a) convey the said package through a wireless channel to the access network and (b) to take negative ouvido is of NAK from the network-level access control access to the transmission medium (MAC); these module configured to determine associated with whether a received NAK with the package that contains video data, and to determine what IP packet contains data that has been lost during transmission; and videoder configured to perform error correction, if the received NAK is associated with a packet that contains video data.

36. A device for implementing error correction video containing a video encoder configured to encode the first frame of video data; a first module configured to generate a packet with the encoded first frame of video data; a transceiver configured to (a) convey the said package through a wireless channel to the access network and (b) to take a negative notice (NAK) from the network-level access control access to the transmission medium (MAC); a second module configured to determine whether the MAC level from the access network NAK before to encode the second frame, and to determine associated with whether a received NAK with the package that contains video data; and a module error correction, configured to perform error correction, if the received NAK is associated with a packet that contains video data.



 

Same patents:

FIELD: physics, communications.

SUBSTANCE: invention relates to multimedia transmission systems, specifically to methods and a device for acquiring services. Proposed is a service acquisition device which has a source coder configured to generate one or more channel switch video (CSV) signals, which is an independently decoded version of a low-resolution video for the selected channel in a received multiplex transmission and associated one or more multimedia signals, an error coder configured to code CSV signals and multimedia signals for formation of coded error blocks, and a linker configured to encapsulate coded error blocks into a multiplex transmission signal.

EFFECT: fast acquisition of a service and/or switching between services in multiplex transmission.

60 cl, 23 dwg

FIELD: physics, communications.

SUBSTANCE: invention relates to transmission of a media stream over an error-prone digital video broadcasting - handheld (DVB-H) channel in which media datagrams are labelled according to a priority, packed in a multiprotocol encapsulation section, unequally protected using forward error-correction codes packed into a traffic stream and transmitted into the channel using packets with time-division. A system and a method are proposed for transmitting a multiplexed service stream over a DVB-H channel. Media IP packets are priority labelled. For each packet with time division, the IP packets are grouped based upon the priority labels. Multi protocol encapsulation - forward error correction (MPE-FEC) matrices are made for different priority labels in each packet with time division. Reed-Solomon code data table (RSDT) columns are computed such that the average service bit rate does not overshoot the maximum allowed bit rate, and protection increases with priority. The application data table (ADT) and RSDT of the MPE-FEC matrices are then encapsulated into MPE-FEC sections.

EFFECT: shorter start delay during reception of an unequally protected priority service bit stream.

21 cl, 10 dwg

FIELD: physics; image processing.

SUBSTANCE: invention relates to a method of buffering multimedia information, as well as a method of decoding a coded stream of images in a decoder, in which the coded stream of images is received in form of transmission blocks which contain multimedia data. A system for processing multimedia data is proposed, which contains a coder for coding images and a buffer for buffering multimedia data. Multimedia data are included in the data transmission blocks. The data transmission blocks are ordered in the transmission sequence, which at least partially differs from the sequence of decoding multimedia data in transmission blocks. There is also definition block, which can set a parametre which indicates the maximum number of data transmission blocks which precede any data transmission block in a stream of packets in the transmission sequence and that data transmission block is tracked in the decoding sequence.

EFFECT: more efficient compression when buffering multimedia information.

32 cl, 7 dwg

FIELD: information technologies.

SUBSTANCE: method and device are suggested for multilevel integration used for elimination of errors. Error is detected in multimedia data on the basis of the first level protocol, and then error detected in multimedia data is masked on the basis of the second level protocol. In one aspect error in multimedia data is eliminated on the basis of communication level protocol, and it is controlled on the basis of transport level protocol. Further distribution of controlled error is determined on the basis of synchronisation level protocol, then error detected in multimedia data is masked on the basis of applied level protocol. Further stage of error elimination and scaling stage are provided.

EFFECT: increased efficiency of multimedia data stream processing by reception of multiple streams of coded multimedia data, eliminating errors in erroneous part of stream and recovering multimedia data from multiple streams.

40 cl, 10 dwg

FIELD: information technology.

SUBSTANCE: invention relates to buffering packets of a media stream during transmission from a transmission device to a receiving device. Media packets are generated from at least one type of media information in a stream generator; at least one transmission frame is generated based on transmitted media packets; transmitted packets are generated from at least one transmission frame and a transmission schedule is generated for transmitted packets. In addition, the first and second steps of hypothetical decoding are executed. The first step of hypothetical decoding is executed in accordance with the transmission schedule, and involves buffering the transmitted packets in accordance with the transmission schedule in the first buffer for hypothetical decoding and output of packets from the first buffer for hypothetical decoding based on the transmission frame. The second step of hypothetical decoding involves controlling occupance rate of the first and second buffer for hypothetical decoding by controlling at least one of the following: operation of the stream generator, generation of at least one transmission frame, transmission schedule.

EFFECT: more efficient buffering of media stream packets.

20 cl, 7 dwg

FIELD: image transferring equipment engineering, possible use in multimedia communications.

SUBSTANCE: in accordance to method, when error codes are detected on receiving side, data of code stream of image with error codes are refused prior to decoding of data of code stream of image, and refused data of code stream of image are replaced with data of code stream of image, positioned in appropriate position of previous frame, and data of code stream of image are encoded continuously. Also, an array of marks is set up for data of code stream of image prior to encoding on receiving side, to perform recording of positions, where error codes have been detected.

EFFECT: possible avoidance of transfer of internal frame images on transmitting side and of frozen images on receiving side, or decrease of their occurrence periods, thus improving quality of image.

7 cl, 2 dwg

FIELD: re-synchronization.

SUBSTANCE: method can be used in decoding channel according to MPEG-4 standard. To provide proper decoding of pressed video data signal, the re-synchronization word RW differs from known words of variable length code VLC as well as from start code of plane of video object and has at least 17 sequent zeros, after which the unit follows, for plane of video object coded to provide two-directional prediction. After error in transmission in pressed video signal is detected, the pressed video data signal can be re-synchronized.

EFFECT: higher efficiency of re-synchronization.

4 cl, 2 dwg

The invention relates to encoding and decoding digital data divided into blocks of digits, in order of importance digits

The invention relates to television, in particular to the processing of the image data, and in particular to a method and apparatus for loop-filtering the image data

FIELD: radio engineering.

SUBSTANCE: invention is related to method, system, transmitter, network element, receiver and software for the system intended for transfer of data symbols, in which one or more data symbols are sent from transmitter to one or more receivers in process of transfer session in mode "point-to-multipoint", specified data symbols are equipped with headers of the first type, which are subordinate to protocol of files delivery, at that one or more symbols of restorative data is sent from data recovery data to one specific receiver from specified receivers in session of data recovery in mode "point-to-point", specified symbols of recovery data are equipped with one or several headers of the second type, which are at least partially subordinate to specified protocol of files delivery.

EFFECT: transfer of data symbols in communication sessions of "point-to-multipoint" mode and "point-to-point" mode.

62 cl, 17 dwg

FIELD: communication means.

SUBSTANCE: invention pertains to wireless communication systems. As per the method, first expected coverage zones are defined for the plurality of transfers subject to transmission within several time intervals. Length of the cyclic prefix for these transfers is selected based on the expected coverage zones. Length of the cyclic prefix for each of the transfers may be selected out of the set of permissible cyclic prefix lengths based on the expected coverage zone for the transfer, dislocation of the pilot-signal, etc. For example, the shortest length of the cyclic prefix may be selected for each of the local transfers, and the longest length of the cyclic prefix may be selected for each of broadcasting transfers. Selected length of the cyclic prefix may be transported to the terminals. Transfers are processed (for example, OFDM-modulation is conducted) on the bases of the selected length of the cyclic prefix. Length of the cyclic prefix may be periodically selected, for example in every super-frame.

EFFECT: reduced negative effect of delays dispersion.

33 cl, 17 dwg

FIELD: physics; communication.

SUBSTANCE: invention relates to wireless communication for advanced block acknowledgement. In one version, a receiving device indicates delay in decoding for an aggregate frame of maximum size with coordination of block acknowledgement, which can be used by a transmitting device to determine which request for block acknowledgement the block acknowledgement is responding to. In another version, a transmission serial number (TSN) can be incorporated into the request for block acknowledgement. The receiving device incorporates a TSN into the corresponding response for acknowledgement. This enables the transmitting device to determine which frames are "in transmission". The TSN can be used to identify blocks. In another version, a TSN can be associated with one or more transmitted frames. Although the TSN is not transmitted with the request for block acknowledgement, the transmitting device can determine which TSN corresponds to the block acknowledgement contained in it. A combination of these methods can be developed. Other various aspects are also presented.

EFFECT: improved block acknowledgement.

13 cl, 21 dwg

FIELD: communication facilities.

SUBSTANCE: invention concerns communication systems. Invention claims methods and systems for application in communication system for selective delay of absent acknowledgement (NAK) transmission after the original NAK requesting for retransmission of damaged packet has already been sent. Receiver launches NAK banning timer associated with specific NAK and bans inclusion of specific NAK into condition reports for receiver till timer-set period expires. Use of NAK banning timer reduced probability of false retransmissions from receiver caused by second NAK from receiver when retransmission process is already launched.

EFFECT: improved efficiency of resource utilisation.

34 cl, 10 dwg

FIELD: physics, radio.

SUBSTANCE: invention concerns field of a radio communication and can be used in radio communication system in which the individual pilot-symbol is transmitted each subscriber. The radio communication device is contained by the addressee who gains the parameter containing the indicator of medium of distribution in which pilots-symbols are transmitted, the selector of a profile board of a pilot-signal which chooses the profile board of the pilot-signal specifying position of pilot-symbols in the frequency field and in temporary field according to the gained parameter, and the transmitter which transmits the signal including the information on the chosen profile board of a pilot-signal. The addressee has or a measuring instrument of quantity of noises, either a measuring instrument of a variance of a delay or the block of an estimate of velocity of motion. The method of transmission of a pilot-symbol is grounded on reception of the parameter containing the indicator of medium of distribution in which pilots-symbols are transmitted, a select of a profile board of the pilot-signal specifying standings of pilots-symbols in the frequency field and in temporary field according to gained parameters and signal transmission, including the information on the chosen profile board of a pilot-signal.

EFFECT: maintenance underload actions of the information of a feedback on throughput capacity of the channel without decrease in efficiency of an information transfer as a result of transmission of pilots-symbols.

15 cl, 17 dwg

FIELD: communications.

SUBSTANCE: method and device for transmission of upstream communication line acknowledgement information (ACK) in communication system which uses multiple access scheme with orthogonal frequency division multiplexing (OFDMA) includes data bit receiving for upstream communication line ACK; output of code words corresponding to data bit; modulation execution by quadrature phase shift keying (QPSK) on characters for ACK vector indices matching to code words for received data bit; execution of inverse fast Fourier (IFFT) on transmission signal containing subcarrier groups to which modulated transmission characters are assigned; and transmission of processed by IFFT transmission signal.

EFFECT: reliability enhancement for transmission of upstream communication line acknowledgement information (ACK) and reduction of service protocol data portion.

49 cl, 8 dwg

FIELD: physics, communication.

SUBSTANCE: invention concerns method of uplink user data transfer control in a mobile communication system. The invention claims a control method for uplink user data transfer control in a mobile communication system where multiple processes of hybrid automatic query to repeat data transfer (HAQR) are applied to uplink user data. The method involves: classification of each HAQR process in radio network controller for each planned transmission process, unplanned transmission process or planned and unplanned transmission process which performs either planned or unplanned transmission; mobile station notification of classification result by radio network controller; and uplink user data transfer for each HAQR process from mobile station to base radio station with the use of planned or unplanned transmission on the basis of classification result sent with notification.

EFFECT: creation of control system for uplink user data transfer, allowing simultaneous reduction of equipment resources assigned for receiving unplanned transmission and setting appropriate data transfer speed for planned transmission.

4 cl, 20 dwg

FIELD: systems for providing for redundancy parameters.

SUBSTANCE: at least one series of parameters of redundancy is chosen from a defined set of series and passed to a terminal device through use of strategy information, indicating the chosen series of parameters. That way, the network operator can choose the strategy for the version of redundancy, which is required for use by the terminal device. In that case, a small volume of signalisation is required between the network and the terminal device.

EFFECT: making an improved scheme for selecting redundancy strategy, through which a load is linked to the signalling system, can be reduced, along with increase in flexibility in choosing.

36 cl, 2 dwg

FIELD: communication systems.

SUBSTANCE: effect is achieved because data block routing device in the network and method for controlling device for routing data blocks in the network identify one or several causes of overload in routing device and integrates information about overload cause into one or several data blocks being transferred.

EFFECT: provision of improved method for controlling overloads in communication system with transmission of data blocks, in which a type of overload notification is used.

8 cl, 5 dwg

FIELD: technology for receiving and decoding data of various users in multi-access communication system with code channel expansion.

SUBSTANCE: usage of auto-regressive smoothing of soft solutions about trustworthiness of receipt of code symbols by multi-user detector, their following decoding with restoration of the whole code word, auto-regression smoothing of restored soft solutions with following soft limitation of hyperbolic tangent function, and also estimation of complex envelope curve at each iteration, provides for increased receipt quality in multi-access communication system with code channel expansion, in other words, increased interference resistance of receiver, increased capacity of communication system, reduced cost of base station of system with code channel expansion.

EFFECT: increased interference resistance of signal receipt in multi-access communication system with code division of channels due to iterative combined detection and decoding of data of various users.

1 cl, 6 dwg

FIELD: communication systems.

SUBSTANCE: when two modulation circuits are accessible, information is modulated in compliance with lower-order modulation circuit in case first product of modulation order by peak velocity is lower than first threshold value and in compliance with higher-order circuit in case first product of modulation order by peak velocity is not lower than first threshold value. Product of modulation order by peak velocity depends here on personal computer size, number of Walsh codes, and number of slots per sub-burst. Second product of modulation order by peak velocity is computed using personal computer size, number of Walsh codes, and number of slots per sub-burst. If first product of modulation order by peak velocity does not exceed second threshold value higher than first one, then lower-order modulation circuit is chosen. If second product of modulation order by peak velocity is higher than second threshold value , higher-order modulation circuit is chosen.

EFFECT: provision for finding optimal modulation circuit for retransmission.

14 cl, 14 dwg

FIELD: communication systems, in particular, method and device for fast repeated transmission of signals in communication system.

SUBSTANCE: in accordance to method, transmitting terminal transfers signals in form of packets onto receiving terminal, if the packet was intended for receiving terminal, and if that is so, receiving terminal demodulates the packet. Receiving terminal then calculates packet quality coefficient and compares computed quality coefficient to quality coefficient contained in the packet. If quality coefficients coincide, packet is redirected for further processing. If quality coefficients do not coincide, receiving terminal dispatches request for repeated packet transmission. Transmitting terminal determines, which packet it is needed to transfer again, based on request of repeated transmission, if delivery of packet in accordance to aforementioned is unsuccessful, an attempt of repeated transmission is made in accordance to common plans, based on order numbers, for example, radio line protocol.

EFFECT: provision of automatic request of repeated transfer with low delay of repeated transfer.

4 cl, 5 dwg

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