[0022] The application will be further described in detail below with reference to the drawings and embodiments. It can be understood that the specific embodiments described here are only used to explain the related invention, but not to limit the invention. In addition, it should be noted that, for ease of description, only the parts related to the relevant invention are shown in the drawings.
[0023] It should be noted that the embodiments in the application and the features in the embodiments can be combined with each other if there is no conflict. Hereinafter, the present application will be described in detail with reference to the drawings and in conjunction with embodiments.
[0024] figure 1 An exemplary system architecture 100 to which an embodiment of the method for switching video streams or the apparatus for switching video streams of the present application can be applied is shown.
[0025] Such as figure 1 As shown, the system architecture 100 may include terminal devices 101, 102, 103, a network 104, and a server 105. The network 104 is used to provide a medium for communication links between the terminal devices 101, 102, 103 and the server 105. The network 104 may include various connection types, such as wired, wireless communication links, or fiber optic cables.
[0026] The user can use the terminal devices 101, 102, and 103 to interact with the server 105 through the network 104 to receive or send messages and so on. Various communication client applications, such as video players, webcast applications, video search applications, and social platform software, may be installed on the terminal devices 101, 102, and 103.
[0027] The terminal devices 101, 102, 103 can be various electronic devices with display screens and support for video playback, including but not limited to smart phones, tablet computers, e-book readers, MP4 (Moving Picture Experts Group Audio Layer IV, moving picture expert compression Standard audio level 4) Players, laptops and desktop computers, etc.
[0028] The server 105 may be a server that provides various services, for example, a background video server that provides support for the playback request information of the video sent on the terminal devices 101, 102, and 103. The background video server can analyze and process the received video playback request information and other data, and feed back the processing result (for example, video stream data) to the terminal device.
[0029] It should be noted that the method for switching video streams provided by the embodiments of the present application is generally executed by the server 105, and accordingly, the device for switching video streams is generally set in the server 105.
[0030] Should understand, figure 1 The number of terminal devices, networks, and servers in the are only illustrative. According to implementation needs, there can be any number of terminal devices, networks and servers.
[0031] Continue to refer figure 2 , Shows the process 200 of an embodiment of the method for switching video streams according to the present application. The method for switching video streams includes the following steps:
[0032] Step 201: In response to receiving the play request information of the video sent by the terminal, obtain the video stream of the video.
[0033] In this embodiment, in response to receiving the video playback request information sent by the user using the terminal through a wired connection or a wireless connection, the method for switching the video stream runs on the electronic device (for example, figure 1 The server shown) can obtain the video stream of the video requested by the user. The above-mentioned video stream refers to the transmission of video data. For example, it can be processed as a stable and continuous stream through the network. The browser or plug-in can display multimedia data before the entire file is transferred. The above-mentioned video stream may include a video stream with a first group of pictures (Group of Pictures, GOP) frame number and a video stream with a second group of pictures frame number. A group of pictures is a group of continuous pictures, and the number of frames in a group of pictures can be a video stream. The number of frames from the first key frame to the previous frame of the second key frame, the second key frame is the next key frame adjacent to the first key frame, where the key frame may also be called It is an I frame, which can also be referred to as an Intra Picture. The I frame is usually the first frame of each GOP. It is appropriately compressed and used as a reference point for random access. It can also be regarded as an image . The number of frames in the first picture group needs to be smaller than the number of frames in the second picture group.
[0034] As an example, when the video stream of the first picture group frame number is IBBPIBBPIBBP, where I is an I frame, B is a B frame, P is a P frame, the B frame is a two-way interpolation frame, and the P frame is a forward Predicted frame, the above I frame is a complete picture, P and B frames record the changes relative to the I frame, then the number of frames in the first picture group is from the first I frame to the second I frame. The number of frames in one P frame, that is, the number of frames in the first picture group is 4; the number of frames in the second picture group needs to be greater than the number of frames in the first picture group, and the number of frames in the second picture group can be greater than 4. Any picture group frame number, for example, when the above-mentioned second picture group frame number is 5, the video stream of the second picture group frame number may be IBBBPIBBBP.
[0035] In some optional implementations of this embodiment, when the above-mentioned electronic device receives the video playback request information sent by the terminal device, the above-mentioned electronic device may obtain the above-mentioned video stream from the buffer of the video stream with the first picture group frame number. The video stream with the first frame number of the video is stored in the first sending queue, and the video stream with the second frame number of the video is obtained from the buffer of the video stream with the second frame number. And store it in the second sending queue. Before the electronic device obtains the video stream from the buffer of the video stream, the electronic device may receive the frame of the video, and when the frame of the video is received, the frame will be stored in the buffer. If the frame is an I frame, then The frames in the above buffer will be cleared and the I frame will be stored in the buffer, so there is one and only one I frame in the group of pictures buffer, and the I frame is the first frame.
[0036] In some alternative implementations of this embodiment, the ratio of the number of frames in the second picture group to the number of frames in the first picture group may be a positive integer. For example, if the number of frames in the first picture group is 30 frames, then The number of frames in the second picture group may be 60 frames, 90 frames, and so on.
[0037] In some optional implementation manners of this embodiment, the video stream with the first number of picture groups may have the same sequence parameter set (Sequence Parameter Sets, SPS) as the video stream with the second number of picture groups. The parameter group may also be referred to as a sequence parameter set, where the sequence parameter group described above is used to describe information that does not often change in the video sequence. In H.264 decoding, first filter the code stream to obtain the parameter group. The parameter group is a method to enhance the error recovery ability by improving the structure of the video stream. For example, when some key information (such as sequence header information) bits are lost It will cause serious negative effects of decoding, and H.264 separates these key information and, by virtue of the design of parameter groups, ensures correct transmission in an error-prone environment.
[0038] Step 202: Send the video stream with the first number of picture group frames to the terminal, search for key frames in the video stream with the first picture group frame number, and extract the decoding timestamp of the key frame.
[0039] In this embodiment, after obtaining the video stream of the first picture group frame number and the video stream of the second picture group frame number in step 201, the electronic device may send the video stream of the first picture group frame number to the terminal device. Video stream. During the sending process of the video stream, the electronic device can search for the key frame in the video stream of the first picture group frame number. After the key frame is found, the electronic device can extract the decoding timestamp of the key frame ( Decoding TimeStamp (DTS), the decoding time stamp can also be called the decoding time stamp. In the digital TV system code stream analysis, when analyzing the digital TV elementary stream (Packetized Elementary Streams, PES), the packaged elementary stream is of non-fixed length, generally the length of one access unit, and one access unit is A video frame can also be an audio frame. In order to achieve synchronization of decoding, a corresponding time mark, that is, a decoding time stamp, is inserted before each segment.
[0040] Step 203: In the video stream of the second number of frames in the picture group, search whether there is a frame with the same decoding time stamp.
[0041] In this embodiment, the above-mentioned electronic device may search in the video stream of the second picture group frame number whether there is the same decoding time stamp as the key frame in the video stream of the first picture group frame number extracted in step 202 Frame. The above electronic device may first extract the decoding timestamp of each frame in the video stream of the second picture group frame number; then, compare with the decoding timestamp of the key frame in the video stream of the first picture group frame number to check whether they are the same .
[0042] Step 204, in response to finding that there is a frame that is the same as the decoding time stamp, further detecting whether the frame is a key frame.
[0043] In this embodiment, when it is found that there is a frame that is the same as the decoding time stamp in the video stream of the second number of frames of the picture group, the electronic device may further detect whether the frame is a key frame.
[0044] Step 205: In response to detecting that the frame is a key frame, send a video stream of the second number of frames in the picture group to the terminal.
[0045] In this embodiment, when it is detected that the above-mentioned frame is a key frame, the above-mentioned electronic device may send the video stream of the second number of frames to the terminal, and stop sending the video stream of the first number of frames, the video to be sent The stream is switched from the video stream with the first picture group frame number to the second picture group frame video stream.
[0046] Further reference image 3 , Which shows a process 300 of another embodiment of a method for switching video streams. The process 300 of the method for switching video streams includes the following steps:
[0047] Step 301: In response to receiving the play request information of the video sent by the terminal, obtain the video stream of the video.
[0048] In this embodiment, in response to receiving the video playback request information sent by the user using the terminal through a wired connection or a wireless connection, the method for switching the video stream runs on the electronic device (for example, figure 1 The server shown) can obtain the video stream of the video requested by the user. The above-mentioned video stream refers to the transmission of video data. For example, it can be processed as a stable and continuous stream through the network. The browser or plug-in can display multimedia data before the entire file is transferred. The above-mentioned video stream may include a video stream with a first picture group frame number and a second picture group frame number video stream. A picture group is a group of continuous pictures, and the picture group frame number can be from the first key frame to the second key frame in the video stream. The number of frames in the previous frame of the second key frame. The second key frame is the next key frame adjacent to the first key frame. The key frame may also be called an I frame or Called an internal picture, the I frame is usually the first frame of each GOP. It is appropriately compressed and used as a reference point for random access. It can also be regarded as an image. The number of frames in the first picture group needs to be smaller than the number of frames in the second picture group.
[0049] Step 302: Send the video stream of the first number of picture group frames to the terminal, and obtain the identifiers of the frames in the video stream of the first number of picture group frames.
[0050] In this embodiment, after obtaining the video stream of the first picture group frame number and the video stream of the second picture group frame number in step 301, the above-mentioned electronic device may send the above-mentioned first picture group frame number to the terminal device. For a video stream, in the process of sending a video stream, each time a frame of picture is sent, the above-mentioned electronic device can obtain the identifier of the above-mentioned frame. Before sending the video stream, the type of the frame can be marked in the header of each frame of the video stream. For example, in H.264, the type of the frame is marked in the slice_header. The above electronic device checks this flag bit. You can get the frame ID.
[0051] Step 303: Using the identifier, search for the key frame in the video stream of the first picture group frame number, and extract the decoding timestamp of the key frame.
[0052] In this embodiment, the video stream of the first picture group frame number includes I frame (key frame), B frame and P frame, and the I frame, B frame and P frame respectively correspond to different identifiers. The above electronic device The identification of the frame obtained in step 302 may be used to search for the key frame in the video stream of the first picture group frame number, and then extract the decoding timestamp of the key frame.
[0053] Step 304: In the video stream with the second number of frames in the picture group, search for whether there is a frame with the same decoding time stamp.
[0054] In this embodiment, the above-mentioned electronic device may search for the video stream with the second number of picture groups to find whether there is the same decoding time stamp as the key frame in the video stream with the first number of picture groups extracted in step 303. frame. The above electronic device may first extract the decoding timestamp of each frame in the video stream of the second picture group frame number; then, compare with the decoding timestamp of the key frame in the video stream of the first picture group frame number to check whether they are the same .
[0055] Step 305: In response to finding that there is a frame that is the same as the decoding time stamp, it is further checked whether the frame is a key frame.
[0056] In this embodiment, when it is found that there is a frame that is the same as the decoding time stamp in the video stream of the second number of frames of the picture group, the electronic device may further detect whether the frame is a key frame.
[0057] Step 306: In response to detecting that the frame is a key frame, send a video stream of the second number of frames in the picture group to the terminal.
[0058] In this embodiment, when it is detected that the above-mentioned frame is a key frame, the above-mentioned electronic device may send the video stream of the second number of frames to the terminal, and stop sending the video stream of the first number of frames, the video to be sent The stream is switched from the video stream with the first picture group frame number to the second picture group frame video stream.
[0059] From image 3 It can be seen that with figure 2 Compared with the corresponding embodiment, the process 300 of the method for switching video streams in this embodiment highlights the step of searching for the key frames in the video stream of the first picture group frame number. Therefore, the solution described in this embodiment can accurately find the key frames in the video stream, so that the picture quality of the video can be improved more quickly.
[0060] Further reference Figure 4 As an implementation of the methods shown in the above figures, this application provides an embodiment of a device for switching video streams, which is similar to figure 2 The method embodiment shown corresponds to that, and the device can be specifically applied to various electronic devices.
[0061] Such as Figure 4 As shown, the apparatus 400 for switching video streams described in this embodiment includes: an acquiring unit 401, an extracting unit 402, a searching unit 403, a detecting unit 404, and a sending unit 405. Wherein, the obtaining unit 401 is configured to obtain a video stream of the video in response to receiving the playback request information of the video sent by the terminal, wherein the video stream includes: a video stream with a first picture group frame number and a second picture For a video stream with the number of frames, the number of picture frames is the number of frames from the first key frame to the previous frame of the second key frame in the video stream, and the second key frame is the same as the first key frame. Next to the next key frame, the number of frames in the first picture group is less than the number of frames in the second picture group; the extraction unit 402 is configured to send the video stream of the first picture group frame number to the terminal, and search for all The key frame in the video stream of the first picture group frame number, and the decoding timestamp of the key frame is extracted; the searching unit 403 is configured to find whether there is a video stream with the second picture group frame number. The frame with the same decoding time stamp; the detecting unit 404 is configured to further detect whether the frame is a key frame in response to finding a frame that is the same as the decoding time stamp; the sending unit 405 is configured to respond to detecting If the frame is a key frame, the video stream of the second number of picture group frames is sent to the terminal.
[0062] In this embodiment, in response to receiving the video playback request information sent by the user using the terminal through a wired connection or a wireless connection, the acquiring unit 401 of the apparatus 400 for switching video streams may acquire the video of the video requested by the user to be played. Stream, where the above-mentioned video stream refers to the transmission of video data. The above-mentioned video stream may include a video stream with a first picture group frame number and a video stream with a second picture group frame number. A picture group is a group of continuous pictures, and the number of picture group frames can be from the first key frame to the second key frame in the video stream. The number of frames in the previous frame of the second key frame. The second key frame is the next key frame adjacent to the first key frame. The key frame may also be called an I frame or Called an internal picture, the I frame is usually the first frame of each GOP. It is moderately compressed and used as a reference point for random access. It can also be regarded as an image. The number of frames in the first picture group needs to be smaller than the number of frames in the second picture group.
[0063] In this embodiment, after the acquisition unit 401 acquires the video stream of the first picture group frame number and the video stream of the second picture group frame number, the extraction unit 402 may send the first picture group to the terminal device. For the video stream with the number of frames, during the sending process of the video stream, the extraction unit 402 can search for the key frames in the video stream with the first picture group frame number. After the key frames are found, the extraction unit 402 can extract the key frames. The decoding timestamp. In the digital TV system code stream analysis, when analyzing the digital TV basic code stream, the packaged basic code stream is of non-fixed length, generally the length of an access unit, and an access unit is a video frame, or it can be For an audio frame, in order to realize the synchronization of decoding, a corresponding time mark, that is, a decoding time stamp, is inserted before each segment.
[0064] In this embodiment, the search unit 403 may search for the video stream with the second picture group frame number to find whether there is a decoding of the key frame in the video stream with the first picture group frame number extracted by the extraction unit 402. Frames with the same time stamp. The searching unit 403 may first extract the decoding timestamp of each frame in the video stream with the second picture group frame number; then, compare it with the decoding timestamp of the key frame in the video stream with the first picture group frame number to check whether the same.
[0065] In this embodiment, when it is found that there is a frame that is the same as the decoding time stamp in the video stream with the second number of frames in the picture group, the detection unit 404 may further detect whether the frame is a key frame.
[0066] In this embodiment, when it is detected that the frame is a key frame, the sending unit 405 may send the video stream with the second number of frames to the terminal, and stop sending the video stream with the first number of frames, which will be sent soon. The video stream is switched from the video stream of the first picture group frame number to the second picture group frame number video stream.
[0067] In some optional implementation manners of this embodiment, the acquiring unit 401 may include a first acquiring module 4011 and a second acquiring module 4012. When the electronic device receives the video playback request information sent by the terminal device, the first acquisition module 4011 may acquire the video of the first picture group frame number of the video from the buffer of the video stream of the first picture group frame number. And store it in the first sending queue. The second acquisition module 4012 acquires the video stream of the second picture group frame number of the video from the buffer of the video stream of the second picture group frame number and stores it in In the second sending queue. Before the acquisition unit 401 acquires the video stream from the buffer of the video stream, the acquisition unit 401 may receive the frame of the video. When the frame of the video is received, the frame will be stored in the buffer. If the frame is an I frame , The frames in the above buffer will be cleared and the I frame will be stored in the buffer, so there is one and only one I frame in the GOP buffer, and the I frame is the first frame.
[0068] In some alternative implementations of this embodiment, the ratio of the number of frames in the second picture group to the number of frames in the first picture group may be a positive integer. For example, if the number of frames in the first picture group is 30 frames, then The number of frames in the second picture group may be 60 frames, 90 frames, and so on.
[0069] In some optional implementations of this embodiment, the video stream with the first number of frames in the picture group may have the same sequence parameter group as the video stream with the number of frames in the second picture group, where the sequence parameter group is used to Describe information that does not change frequently in a video sequence. In H.264 decoding, first filter the code stream to obtain the parameter group. The parameter group is a method to enhance the error recovery ability by improving the structure of the video stream. For example, when some key information (such as sequence header information) bits are lost It will cause serious negative effects of decoding, and H.264 separates these key information and, by virtue of the design of parameter groups, ensures correct transmission in an error-prone environment.
[0070] In some optional implementation manners of this embodiment, the aforementioned extraction unit 402 may include an acquisition module 4021 and a search module 4022. In the process of sending the video stream, each time a frame of picture is sent, the above-mentioned obtaining module 4021 may obtain the identifier of the above-mentioned frame. Before sending the video stream, the type of this frame can be marked in the header of each frame of the video stream. After that, the searching module 4022 may use the frame identifiers obtained in the obtaining module 4021 to search for key frames in the video stream with the first number of frames in the picture group.
[0071] Reference below Figure 5 , Which shows a schematic structural diagram of a computer system 500 suitable for implementing the server of the embodiment of the present application.
[0072] Such as Figure 5 As shown, the computer system 500 includes a central processing unit (CPU) 501, which can execute various programs according to a program stored in a read-only memory (ROM) 502 or a program loaded from a storage portion 508 into a random access memory (RAM) 503. Kind of appropriate actions and processing. In the RAM 503, various programs and data required for the operation of the system 500 are also stored. The CPU501, ROM502, and RAM503 are connected to each other through a bus 504. An input/output (I/O) interface 505 is also connected to the bus 504.
[0073] The following components are connected to the I/O interface 505: an input part 506 including a keyboard, a mouse, etc.; an output part 507 including a cathode ray tube (CRT), a liquid crystal display (LCD), etc. and speakers, etc.; a storage part 508 including a hard disk, etc. ; And a communication section 509 including a network interface card such as a LAN card, a modem, and the like. The communication section 509 performs communication processing via a network such as the Internet. The driver 510 is also connected to the I/O interface 505 as needed. A removable medium 511, such as a magnetic disk, an optical disk, a magneto-optical disk, a semiconductor memory, etc., is installed on the drive 510 as needed, so that the computer program read from it is installed into the storage portion 508 as needed.
[0074] In particular, according to an embodiment of the present disclosure, the process described above with reference to the flowchart can be implemented as a computer software program. For example, an embodiment of the present disclosure includes a computer program product, which includes a computer program tangibly contained on a machine-readable medium, and the computer program includes program code for executing the method shown in the flowchart. In such an embodiment, the computer program may be downloaded and installed from the network through the communication part 509, and/or installed from the removable medium 511.
[0075] The flowcharts and block diagrams in the drawings illustrate the possible implementation of the system architecture, functions, and operations of the system, method, and computer program product according to various embodiments of the present application. In this regard, each block in the flowchart or block diagram may represent a module, program segment, or part of code, and the above-mentioned module, program segment, or part of code contains one or more for realizing the specified logic function Executable instructions. It should also be noted that, in some alternative implementations, the functions marked in the block may also occur in a different order from the order marked in the drawings. For example, two blocks shown in succession can actually be executed substantially in parallel, and they can sometimes be executed in the reverse order, depending on the functions involved. It should also be noted that each block in the block diagram and/or flowchart, and the combination of the blocks in the block diagram and/or flowchart, can be implemented by a dedicated hardware-based system that performs the specified functions or operations Or it can be realized by a combination of dedicated hardware and computer instructions.
[0076] The units involved in the embodiments described in the present application can be implemented in software or hardware. The described unit may also be provided in the processor. For example, it may be described as: a processor includes an acquiring unit, an extracting unit, a searching unit, a detecting unit, and a sending unit. Among them, the names of these units do not constitute a limitation on the unit itself under certain circumstances. For example, the acquisition unit can also be described as "a unit for acquiring a video stream of a video."
[0077] As another aspect, the present application also provides a non-volatile computer storage medium. The non-volatile computer storage medium may be the non-volatile computer storage medium included in the above-mentioned device in the above-mentioned embodiment; or It is a non-volatile computer storage medium that exists alone and is not assembled into the terminal. The aforementioned non-volatile computer storage medium stores one or more programs. When the aforementioned one or more programs are executed by a device, the aforementioned device: in response to receiving the video playback request information sent by the terminal, acquire the video The video stream, wherein the video stream includes: a video stream with a first picture group frame number and a second picture group frame number video stream, and the picture group frame number is from the first key frame to the second key frame in the video stream The number of frames in the previous frame, the second key frame is the next key frame adjacent to the first key frame, and the number of frames in the first picture group is smaller than the number of frames in the second picture group; Send the video stream of the first picture group frame number to the terminal, search for key frames in the video stream of the first picture group frame number, and extract the decoding timestamp of the key frame; In the video stream with the number of frames in the picture group, search whether there is a frame that is the same as the decoding time stamp; in response to finding that there is a frame that is the same as the decoding time stamp, further detecting whether the frame is a key frame; If it is detected that the frame is a key frame, the video stream of the second number of picture group frames is sent to the terminal.
[0078] The above description is only a preferred embodiment of the present application and an explanation of the applied technical principles. Those skilled in the art should understand that the scope of the invention involved in this application is not limited to the technical solution formed by the specific combination of the above technical features, and should also cover the above technical features without departing from the inventive concept. Other technical solutions formed by any combination of its equivalent features. For example, the above-mentioned features and the technical features disclosed in this application (but not limited to) with similar functions are mutually replaced to form a technical solution.
