CN101686391A - Video coding/decoding method and device as well as video playing method, device and system - Google Patents

Abstract

The embodiment of the invention discloses a video encoding/decoding method and device, and a video playing method, device and system, and relates to the technical field of communication. In order to solve the problem of the same live channel in the prior art, since the user accesses at different times and the current access frame is not an I frame, the streaming media server always starts to send the user an I frame according to the I frame closest to the user's current access frame in the buffer area. Sending data, resulting in the same time, users who access at different times see different programs, so that the time delay between the programs that users watch and the programs that are played in real time is invented. An embodiment of the present invention provides a video encoding method, the method comprising: an encoder performs inter-frame encoding on a source image into a P frame; performs intra-frame encoding on the source image, and obtains an I frame corresponding to the P frame; The I-frame corresponding to the P-frame is stored in the buffer of the encoder. Adoption of the present invention can enable access users to watch live programs in real time.

Description

Video encoding/decoding method, device and video playback method, device and system

technical field

The invention relates to the field of communication technology, in particular to video codec technology.

Background technique

Due to the real-time nature of live broadcast data, users are required to watch the same channel no matter when they access it, and the programs they watch are the same. In fact, each client is required to receive the same media data almost at the same time. Streaming media is generally transmitted using an image sequence such as "IPPPPPPPPI", wherein, in the string of double quotes, I represents an I frame, and P represents a P frame. Because the P frame must be decoded according to the I frame, if the user does not access when the I frame is sent, that is, the first data received by the client is not an I frame, and the client cannot decode it until it receives the I frame. next I-frame. In this way, a serious blurred screen or black screen will inevitably appear in a short period of time from the moment when the user switches to the arrival of the next I frame. In fact, this problem is not only encountered at the time of access, but also in scenarios such as bit rate switching, channel switching, and advertisement insertion. In order to eliminate the blurry or black screen phenomenon when accessing/switching/inserting scenes, the server is required to send I-frame data first when the user accesses/switches/inserts.

In the process of realizing the present invention, the inventor finds that there are at least the following problems in the prior art:

In the streaming media server, for each live channel, a buffer area is created, which buffers data between at least two I frames, that is, the buffer area is required to have at least one complete I frame data, and other P frames and B The frame data also needs to be cached. When the user accesses and the current frame is not an I frame, as shown in Figure 1, the latest I frame data is found from the cache data, and the I frame data starts to provide services for the user. In this way, for the same live channel, since the user access frame is not an I frame, the streaming media server always starts to send data to the user according to the I frame closest to the user's current access frame in the buffer area, thereby causing the same time , Different users see different programs, and cannot watch the current live program in real time, and there is a certain delay. Because when the user accesses, the current frame is not an I frame, and the program that the user watches is always the program played from the I frame closest to the access user frame in the buffer area.

In the streaming media server, for each live channel, the latest complete I-frame data can be cached, and updated in real time each time a complete new I-frame data is received. When a new user comes in and the current frame is not an I frame, PSS (Packet-switched Streaming Server, packet domain streaming server) sends the cached I frame data to the user first, and then sends the current frame, the described The current frame is a P frame or a B frame. As shown in Figure 1, that is, after the PSS sends the I0 frame data first, it continues to provide services following the P4 frame data. However, sending the current frame after sending the I frame in the buffer area is equivalent to losing the frame data between the P frame or the B frame of the recent I frame to the current frame, as shown in Figure 1, which is equivalent to losing P2, Data of P2 and P3 frames. Therefore, image blurring or mosaic phenomenon inevitably occurs during the initial access.

Contents of the invention

In order to solve the problem in the prior art, since the current access frame is not an I frame when the user accesses the same live channel, the streaming media server always starts to send the I frame to the user according to the I frame closest to the user's current access frame in the buffer area. data, resulting in different programs seen by users accessing at different times at the same time, causing delay problems between the programs watched by users and the programs played in real time. Embodiments of the present invention provide a video editing Decoding method, device and video playing method, device and system to solve time delay problem.

In realizing the technical solution of the present invention, an embodiment of the present invention provides a video coding method, the method including:

The encoder inter-codes the source image into a P frame;

Intra-coding the source image to obtain an I frame corresponding to a P frame;

The I-frame corresponding to the P-frame is stored in the buffer of the encoder.

In realizing the technical solution of the present invention, an embodiment of the present invention provides a video decoding method, the method including:

Receive the video frame forwarded by the streaming media server;

If the received video frame is a P frame, the I frame corresponding to the current P frame is obtained, and decoding is performed with reference to the I frame corresponding to the current P frame.

In realizing the technical solution of the present invention, the embodiment of the present invention provides a video playback method, the method including:

If the received video frame is a P frame, the streaming media server sends an I frame request message corresponding to the P frame;

The streaming media server receives the I frame, and the I frame is obtained by the encoder device by intra-coding the source image corresponding to the P frame according to the request for obtaining the I frame;

The streaming media server forwards the I frame to the client device, so that the client device decodes and plays the video P frame corresponding to the received I frame according to the I frame.

In realizing the technical solution of the present invention, the embodiment of the present invention also provides a video coding device, the device including:

Encoding unit: used to perform intra-frame encoding on the source image when the encoder performs inter-frame encoding of the source image into a P frame, and obtain an I frame corresponding to the P frame;

A cache unit: used to store the I frame corresponding to the P frame in the cache of the encoder.

In realizing the technical solution of the present invention, the embodiment of the present invention also provides a video decoding device, which includes:

The receiving unit is used to receive the video frame forwarded by the streaming media server;

The decoding unit is configured to obtain an I frame corresponding to the current P frame if the received video frame is a P frame, and decode with reference to the I frame corresponding to the current P frame.

In realizing the technical solution of the present invention, the embodiment of the present invention also provides a video playback device, which includes:

Information sending unit: for if the received video frame is a P frame, the streaming media server sends an I frame request message corresponding to the P frame;

The information receiving unit: used for the streaming media server to receive the I frame, the I frame is obtained by the encoder device by intra-coding the source image corresponding to the P frame according to the request for obtaining the I frame; it is also used for Through the message channel, the streaming media server receives the response message for obtaining the I frame;

An information forwarding unit: used for the streaming media server to forward the I frame to the client device, so that the client device decodes and plays the video P frame corresponding to the received I frame according to the I frame.

In realizing the technical solution of the present invention, the embodiment of the present invention also provides a video playback system, the system including:

The request receiving unit is used for if the received video frame is a P frame, the encoder device receives the I frame request message sent by the streaming media server to obtain the corresponding I frame of the P frame;

The information acquisition unit is used for the encoder device to perform intra-frame encoding on the source image corresponding to the current P frame according to the acquisition I frame request message, and acquire the I frame corresponding to the current P frame;

The information sending unit is used for the encoder device to send the I frame to the streaming media server; through the message channel, sending the response message for obtaining the I frame to the streaming media server; through the temporary channel, sending The I frame is issued to the streaming media server;

A forwarding unit, configured for the streaming media server to forward the I frame to the client device;

The decoding and playing unit, the client device decodes and plays the video P frame corresponding to the received I frame according to the I frame.

The video playback method, device and system provided by the embodiments of the present invention and the video encoding/decoding method and device, when the source image is inter-frame encoded into a P frame on the encoder side, the P frame is encoded while the P frame is corresponding Encoding of the I frame, and storing it in the cache of the encoder for later use; when the packet domain streaming server judges that the current access frame is not an I frame, it initiates a request to obtain the I frame, and the encoder device will obtain the frame according to the request I frame and forward the I frame to the client device through the packet domain streaming media server, so that the client device can decode the currently accessed P frame according to the I frame, so that the user accesses, switches/inserts , the image can be watched clearly in real time; the present invention decodes according to the I frame, so that users who access at different times can directly obtain the I frame corresponding to the current access P frame for live broadcast, thereby not only reducing the It reduces the playback delay of the live channel, and can also clearly decode the P frame, improving the clarity of the decoded image.

Description of drawings

FIG. 1 is a schematic diagram of playing a frame from a user access point in the prior art;

FIG. 2 is a flowchart of a video encoding method provided by an embodiment of the present invention;

FIG. 3 is a flowchart of a video decoding method provided by an embodiment of the present invention;

FIG. 4 is a flowchart of a video playback method provided by an embodiment of the present invention;

Fig. 5 is a processing flowchart for implementing a video playback method when a user accesses according to an embodiment of the present invention;

FIG. 6 is a schematic structural diagram of a video encoding device provided by an embodiment of the present invention;

FIG. 7 is a schematic structural diagram of a video decoding device provided by an embodiment of the present invention;

FIG. 8 is a schematic structural diagram of a video playback device provided by an embodiment of the present invention;

FIG. 9 is a schematic structural diagram of a video playback system provided by an embodiment of the present invention;

FIG. 10 is a schematic structural diagram of a data body in a message channel provided by an embodiment of the present invention;

FIG. 11 is a schematic diagram of a video coding method provided by an embodiment of the present invention.

Detailed ways

A video encoding/decoding method and device, and a video playing method and device provided in the embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

As shown in Figure 2, a video encoding method provided by an embodiment of the present invention, in the process of implementing the embodiment of the present invention, the method includes:

201: The encoder performs inter-frame encoding of the source image into a P frame;

202: Perform intra-frame encoding on the source image to obtain an I frame corresponding to a P frame;

203: Store the I frame corresponding to the P frame in the cache of the encoder.

Wherein, in this embodiment, the step 202 can have three different encoding methods respectively:

The first encoding method for synthesizing I frames is:

Obtain the original image of the reference frame of the current P frame;

The original image of the reference frame of the current P frame is used as a source image, and intra-frame encoding is performed to obtain an I frame corresponding to the P frame.

The second encoding method for synthesizing I frames is:

Obtain the reconstructed image of the reference frame of the current P frame;

Using the reconstructed image of the reference frame of the current P frame as a source image, perform intra-frame encoding to obtain an I frame corresponding to the P frame.

The third encoding method for synthesizing I frames is:

Obtain an image synthesized from source images of at least two reference frames of the current P frame;

An image synthesized from original images of at least two reference frames of the current P frame is used as a source image, and intra-frame coding is performed to obtain an I frame corresponding to the P frame.

Further, in this embodiment, the step 203 may include:

Set the size of the encoder cache according to the current encoding frame of the encoder and the current forwarding frame of the packet domain streaming server;

The I frame corresponding to the P frame is updated and stored in real time according to the size of the encoder cache.

As shown in Figure 3, a video decoding method provided by an embodiment of the present invention, in the process of implementing the embodiment of the present invention, the method includes:

301: Receive the video frame forwarded by the streaming media server;

302: If the received video frame is a P frame, acquire an I frame corresponding to the current P frame, and decode with reference to the I frame corresponding to the current P frame. Wherein, if the received video frame is a P frame, the I frame corresponding to the current P frame is obtained, and the step of decoding with reference to the I frame corresponding to the current P frame includes:

According to the received video frame, it is judged that the currently received video frame is a P frame;

Obtain an I frame corresponding to the current P frame, and decode with reference to the I frame corresponding to the current P frame.

In the video encoding/decoding method provided by the embodiment of the present invention, the source image is inter-coded into a P frame by the encoder, and at the same time, the source image is intra-coded, and the I frame corresponding to the P frame is obtained and cached in In the encoder, when the access is a P frame, the user can obtain the I frame corresponding to the P frame in real time for decoding, so that the user can watch the program of the live channel without delay.

As shown in Figure 4, the embodiment of the present invention provides a video playback method, the method, including:

401: If the received video frame is a P frame, the streaming media server sends an I frame request message corresponding to the P frame;

402: The streaming media server receives an I frame, and the I frame is obtained by the encoder device by intra-coding the source image corresponding to the P frame according to the request for obtaining the I frame; that is, through the message channel, the streaming media The server receives the response message for acquiring the I frame; the streaming media server receives the I frame through the temporary channel.

403: The streaming media server forwards the I frame to the client device, so that the client device decodes and plays the video P frame corresponding to the received I frame according to the I frame.

Wherein, the request message at least carries the live channel ID, the current frame ID, the receiving port of the temporary channel and the command indication value; the response message carries at least the live channel ID, the current frame ID, the receiving port of the temporary channel and the command indication value.

As shown in FIG. 5 , the embodiment of the present invention provides a processing flowchart for implementing a video playback method when the user accesses; in the process of realizing the embodiment of the present invention, the specific steps are as follows:

501. The client device sends an on-demand request according to user needs;

502. PSS on-demand responds to the request after receiving the on-demand request;

503, PSS judges whether the current frame is an I frame, if it is an I frame, directly enters step 508; if not an I frame, directly proceeds to step 504;

504. The PSS sends an I frame requesting the current frame; wherein, the request message requesting the I frame of the current frame may be sent to the encoder device through a message.

505. The encoder device performs I frame synthesis processing according to the received request for obtaining the I frame of the current frame; the implementation of the present invention can perform synthesis I frame processing through the video encoding method as described above:

In the process of obtaining and synthesizing I frames in the embodiment of the present invention, take the process of accessing the user's play frame shown in Figure 1 as an example, in the embodiment of the present invention for I0, P1, P2, P3, P4, P5, The encoding process of P6, P7, P8, and I9 frames is shown in FIG. 11 . If Fn is to be encoded as a P frame, in addition to performing the normal processes of 1 and 2 to encode the source image of Fn into a P frame, it is also necessary to perform 3 processes, and perform intra-frame encoding through process 3 to generate an image corresponding to the source image of the Fn. Corresponding I frame, described I frame is stored in among the In such as Fig. 7; If Fn will be encoded as I frame, In is all the same with the data output to NAL; If Fn will be encoded as B frame, because The B frame will not be referenced by other frames, which means that Fn will definitely not be referenced by subsequent frames, and there is no need to generate I frame data corresponding to Fn. Wherein, the Fn may be the source image of the reference frame of the current frame, or the reconstructed image of the reference frame of the current frame, or an image synthesized from multiple reference frames of the current frame.

506. The encoder device responds to the request of the PSS, and notifies the packet domain streaming media server of the response message of the synthesized I frame through the message channel;

Wherein, the data body structure of the request message and the response message transmitted through the message channel may be as shown in FIG. A live channel can be uniquely identified according to the channel ID. Sometimes the channel ID may fill in the multicast IP of the live channel; the meaning of the command indication value is as follows: 01 means that the PSS requests the Encoder for the synthesized I frame corresponding to the current frame, and 02 means that the Encoder responds to the PSS request. The specific usage method of this data body structure is: when PSS needs to request the synthesized I frame of a certain P frame, first, construct a piece of data according to the above data body structure, and establish a short TCP connection with the Encoder to obtain the synthesized I frame data and then disconnect Open; then, use the TCP protocol to transmit the above constructed data to the Encoder. After the Encoder receives the PSS request, after synthesizing the I frame according to the specified method of synthesizing the I frame, first, construct a piece of data according to the above data body structure, and respond the data to the PSS request through the message channel, and then synthesize the I frame through the temporary channel The frame data is sent to the port specified in the data body structure, so that the entire transmission interaction process is completed.

507. The encoder device sends the data of the I frame through the temporary channel; and delivers the I frame to the packet-domain streaming media server through the temporary channel.

The request message and the response message at least carry the receiving port of the live channel ID, the current frame ID, the temporary channel and the command indication value; the message channel is at least based on TCP (Transfer Control Protocol, Transmission Control Protocol), UDP (User Datagram Protocol, User Datagram Protocol); the temporary channel is based on RTP (Real-time Transport Protocol, real-time transport protocol).

508. The PSS sends the data of the I frame;

509. The PSS subsequently sends a normal live stream according to a common live broadcast process.

Further speaking, according to the frame forwarded by the packet domain streaming media server, the client device judges whether the current received frame is an I frame;

If the currently received frame is an I frame, the I frame is played directly; if the current frame is not an I frame, and its reference frame does not exist, the I frame corresponding to the current P frame is obtained for decoding. Wherein, in the above-mentioned third way of synthesizing the I frame, the process of synthesizing the I frame changes the reference relationship of the reference frame of the current frame. For example: the reference frames Pi, Pj, and Pk of a certain Pn frame, because Pi, Pj, and Pk are synthesized into an I frame, only one sequence number of the frame can be reserved, so some macroblocks of Pn cannot be processed according to the frame indicated by the message. No. to find the reference frame, so that it cannot be decoded, so the current frame can be decoded according to the synthetic I frame mentioned in the implementation of the present invention. Another most common situation is that due to the instability of the wireless network, packet loss is very likely to occur. Assuming that the reference frame Pi of Pn is lost, the subsequent P frame cannot be decoded until the next I frame arrives. In some cases, the I frame may also be obtained according to the embodiment of the present invention, so as to decode the current frame.

As shown in FIG. 6, an embodiment of the present invention provides a video encoding device, which includes:

Encoding unit 601: used to perform intra-frame encoding on the source image when the encoder performs inter-frame encoding on the source image into a P frame, and obtain an I frame corresponding to the P frame;

Buffering unit 602: configured to store the I frame corresponding to the P frame in the buffer of the encoder.

Wherein, the video encoding device also includes:

Source image acquisition unit 603: used to acquire the original image of the reference frame of the current P frame, the reconstructed image, or an image synthesized from the original images of at least two reference frames of the current P frame.

The cache unit 602 further includes:

Cache setting subunit: used to set the size of the encoder cache according to the current encoding frame of the encoder and the current forwarding frame of the packet domain streaming media server;

Update storage sub-unit: for updating and storing the I frame corresponding to the P frame in real time according to the size of the encoder cache.

As shown in FIG. 7, an embodiment of the present invention provides a video decoding device, which includes:

Receiving unit 701: for receiving the video frame forwarded by the streaming media server;

The decoding unit 702: if the received video frame is a P frame, obtain an I frame corresponding to the current P frame, and decode with reference to the I frame corresponding to the current P frame.

As shown in Figure 8, an embodiment of the present invention provides a video playback device; the device includes:

Information sending unit 801: used for, if the received video frame is a P frame, the streaming media server sends an I frame request message corresponding to the P frame;

The information receiving unit 802: used for the streaming media server to receive the I frame, the I frame is obtained by the encoder device by intra-coding the source image corresponding to the P frame according to the request for obtaining the I frame; Through the message channel, the streaming media server receives the response message for obtaining the I frame;

The information forwarding unit 803 is used for the streaming media server to forward the I frame to the client device, so that the client device decodes and plays the video P frame corresponding to the received I frame according to the I frame.

As shown in Figure 9, an embodiment of the present invention provides a video playback system; the system includes:

Request receiving unit 901: used for, if the received video frame is a P frame, the encoder device receives the I frame request message corresponding to the P frame sent by the streaming media server;

The information acquisition unit 902 is used for the encoder device to perform intra-frame encoding on the source image corresponding to the current P frame according to the acquisition I frame request, and acquire the I frame corresponding to the current P frame;

Information sending unit 903: used for the encoder device to send the I frame to the streaming media server; that is, send the response message for obtaining the I frame to the packet domain streaming media server through a message channel; channel, and deliver the I frame to the packet-domain streaming media server.

A forwarding unit 904, configured for the streaming media server to forward the I frame to the client device;

The decoding and playing unit 905, the client device decodes and plays the video P frame corresponding to the received I frame according to the I frame.

Further, the decoding playback unit 905 also includes:

Error-tolerant processing subunit: used to judge the currently received video frame as a P frame according to the received video frame, and the client device decodes the received video P frame according to the I frame corresponding to the current P frame play.

In the video playback method, device and system provided by the embodiments of the present invention, when the source image is inter-coded into a P frame on the encoder side, the corresponding I frame of the P frame is coded while the P frame is coded, and its Stored in the cache of the encoder for later use; when the packet domain streaming media server judges that the current access frame is not an I frame, it initiates a request to obtain an I frame, and the encoder device will obtain the I frame according to the request and send the I frame It is forwarded to the client device through the packet domain streaming media server, so that the client device can decode the currently accessed P frame according to the I frame, so that when the user accesses, switches/inserts the broadcast, he can clearly watch it in real time Image; with the prior art, because the time when the user accesses is different and the current access frame is not an I frame, the streaming media server always starts to send data to the user according to the I frame closest to the user's current access frame in the cache area, Thereby causing the same time, different programs seen by users who access at different times, so that the time delay generated between the programs watched by the users and the programs played in real time, the present invention decodes according to the I frame, which can make different Users who access at any time can directly obtain the I frame corresponding to the currently accessed P frame for live broadcast, which not only reduces the playback delay of the live channel, but also can clearly decode the P frame, improving the quality of the decoded image clarity.

Through the description of the above embodiments, those of ordinary skill in the art can understand that all or part of the steps in the method of the above embodiments can be completed by instructing related hardware through a program, and the program can be stored in a computer-readable When the program is executed, the program includes the steps of the above-mentioned method embodiment, the storage medium described, such as: ROM/RAM, magnetic disk, optical disk, etc.

The above is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Anyone skilled in the art can easily think of changes or substitutions within the technical scope disclosed in the present invention. Should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims (17)

1, a kind of method for video coding is characterized in that, comprising:

It is the P frame that encoder carries out interframe encode with source images;

Described source images is carried out intraframe coding, obtain and the corresponding I frame of P frame;

Be stored in the buffer memory of encoder with the corresponding I frame of P frame described.

2, method for video coding according to claim 1 is characterized in that, described source images is carried out intraframe coding, obtains the step with the corresponding I frame of P frame, comprising:

Obtain the original image of the reference frame of current P frame;

Original image with the reference frame of described current P frame carries out intraframe coding, obtains and the corresponding I frame of P frame.

3, method for video coding according to claim 1 is characterized in that, described source images is carried out intraframe coding, obtains the step with the corresponding I frame of P frame, comprising:

Obtain the reconstructed image of the reference frame of current P frame;

Reconstructed image with described current P frame reference frame carries out intraframe coding, obtains and the corresponding I frame of P frame.

4, method for video coding according to claim 1 is characterized in that, described source images is carried out intraframe coding, obtains the step with the corresponding I frame of P frame, comprising:

Obtain the synthetic image of original image of at least two width of cloth reference frames of current P frame;

The image that the original image of at least two width of cloth reference frames of described current P frame is synthetic carries out intraframe coding, obtains and the corresponding I frame of P frame.

5, method for video coding according to claim 1 is characterized in that, described and the corresponding I frame of P frame is stored in the step in the buffer memory of encoder, comprising:

The size of encoder buffer is set according to the current transmitted frame of the current encoded frame of encoder and streaming media server;

With the described and corresponding I frame of P frame, carry out the real-time update storage according to the size of described encoder buffer.

6, a kind of video encoding/decoding method is characterized in that, comprising:

The frame of video of receiving stream media server forwards;

If when the frame of video that receives is the P frame, obtain and the corresponding I frame of current P frame, decode with reference to the corresponding I frame of described and current P frame.

7, video encoding/decoding method according to claim 6 is characterized in that, when being the P frame as if the frame of video that receives, obtains and the corresponding I frame of current P frame, and the step with reference to the corresponding I frame of described and current P frame is decoded comprises:

According to the frame of video that receives, the frame of video of judging current reception is the P frame;

Obtain and the corresponding I frame of current P frame, decode with reference to the corresponding I frame of described and current P frame.

8, a kind of video broadcasting method is characterized in that, comprising:

When if the frame of video that receives is the P frame, streaming media server sends the I frame request message that obtains described P frame correspondence;

Streaming media server receives the I frame, and described I frame is that encoder device carries out intraframe coding according to the request of the described I of obtaining frame with the pairing source images of described P frame and obtains;

Streaming media server is transmitted to client device with described I frame, so as described client device according to described I frame to the broadcast of decoding of the video P frame of the described I frame correspondence that receives.

9, described according to Claim 8 video broadcasting method is characterized in that, obtains the request of I frame according to described, and streaming media server receives the step of I frame, comprising:

By message channel, streaming media server receives the described response message that obtains the I frame;

By occasional passage, streaming media server receives described I frame.

10, according to the described video broadcasting method of claim 9, it is characterized in that, carry the receiving port and the order indicated value of direct broadcast band ID, present frame ID, occasional passage in the described request message at least; At least carry the receiving port and the order indicated value of direct broadcast band ID, present frame ID, occasional passage in the described response message.

11, a kind of video coding apparatus is characterized in that, comprising:

Coding unit is used at encoder source images being carried out interframe encode when being the P frame, and described source images is carried out intraframe coding, obtains and the corresponding I frame of P frame;

Buffer unit is used for described and the corresponding I frame of P frame are stored in the buffer memory of encoder.

12, video coding apparatus according to claim 11 is characterized in that, also comprises:

Source images acquiring unit: the synthetic image of original image of at least two width of cloth reference frames of original image, reconstructed image or current P frame that is used to obtain the reference frame of current P frame.

13, video coding apparatus according to claim 11 is characterized in that, described buffer unit further comprises:

Buffer memory is provided with subelement: the size that is used for being provided with according to the current transmitted frame of the current encoded frame of encoder and streaming media server encoder buffer;

Updated stored subelement: be used for the described and corresponding I frame of P frame, carry out the real-time update storage according to the size of described encoder buffer.

14, a kind of video decoder is characterized in that, comprising:

Receiving element is used for the frame of video of receiving stream media server forwards;

Decoding unit is used for obtaining and the corresponding I frame of current P frame when if the frame of video that receives is the P frame, decodes with reference to the corresponding I frame of described and current P frame.

15, a kind of video play device is characterized in that, comprising:

Information transmitting unit: be used for when if the frame of video that receives is the P frame, streaming media server sends the I frame request message that obtains described P frame correspondence;

Information receiving unit: be used for streaming media server and receive the I frame, described I frame is that encoder device carries out intraframe coding according to the request of the described I of obtaining frame with the pairing source images of described P frame and obtains; Also be used for by message channel, streaming media server receives the described response message that obtains the I frame;

The information retransmission unit: be used for streaming media server described I frame be transmitted to client device so that described client device according to described I frame to the broadcast of decoding of the video P frame of the described I frame correspondence that receives.

16, a kind of audio/video player system is characterized in that, comprising:

The request receiving element is used for when if the frame of video that receives is the P frame I frame request message that obtains described P frame correspondence that encoder device receiving stream media server sends;

Information acquisition unit is used for encoder device according to the described I of obtaining frame request message, and the pairing source images of described current P frame is carried out intraframe coding, obtains and the corresponding I frame of current P frame;

Information issues the unit, is used for encoder device described I frame is handed down to described streaming media server; By message channel, the response message that issues the described I of obtaining frame is given streaming media server; By occasional passage, issue described I frame and issue to streaming media server;

Retransmission unit is used for streaming media server described I frame is transmitted to client device;

Decoding broadcast unit, client device according to described I frame to the broadcast of decoding of the video P frame of the described I frame correspondence that receives.

According to the described video play device of claim 16, it is characterized in that 17, described decoding broadcast unit comprises:

The fault-tolerant processing subelement is used for according to the frame of video that receives, and the frame of video of judging current reception is the P frame, client device according to the corresponding I frame of described and current P frame to the broadcast of decoding of the video P frame of described reception.

Images