WO2012028096A1

WO2012028096A1 - Method and apparatus for downloading audio-video file

Info

Publication number: WO2012028096A1
Application number: PCT/CN2011/079149
Authority: WO
Inventors: 刘俊
Original assignee: 腾讯科技（深圳）有限公司
Priority date: 2010-09-01
Filing date: 2011-08-31
Publication date: 2012-03-08
Also published as: CN102387177A; CN102387177B

Abstract

Disclosed are a method and apparatus for downloading an audio-video file, which belongs to the field of data processing. The method comprises: downloading various segments of an audio-video file selected by a user and carrying out structural analysis on each of the segments; judging whether each of the segments meets a format conversion condition according to the analysis results; and converting the format of each of the segments into a format matching that of a specified device when each of the segments meets the format conversion condition. In the present invention, a downloaded audio-video file can be made to meet the audio-video file format requirements of various devices by carrying out format conversion thereon at the time of downloading it, so that the format barrier at the time of downloading the audio-video file is eliminated and user operation can be simplified since there is no need to separately download a format conversion tool.

Description

Method and apparatus for downloading audio and video files, the present application claims priority to Chinese Patent Application No. 201010272312.X, filed on September 1, 2010, entitled "Downloading Method and Apparatus for Video Files", The entire contents are incorporated herein by reference. Technical field

The present invention relates to the field of data processing, and in particular, to a method and an apparatus for downloading audio and video files. Background of the invention

With the gradual improvement of multimedia entertainment functions, the general user equipment provides video and audio playback functions. However, due to the limited format of audio and video files supported by the audio and video playback functions of some user equipments, and the need to obtain audio and video files from the Internet, and the variety of audio and video files on the Internet, the audio and video files on the Internet are directly downloaded to the user equipment. It is often impossible to play on the top.

In order to enable the audio and video files to be played normally on the user equipment, an implementation method requires two processes of downloading and format conversion, that is, downloading the video and audio files first, and then the user converts the downloaded video and audio files according to the format conversion tool, and In the format conversion, the format conversion tool needs to be downloaded separately. Another implementation method is to set up different user equipment zones through some video resource websites to meet the specific requirements of different user equipments for the audio and video formats.

In the process of implementing the present invention, the inventors have found that the prior art has at least the following disadvantages: Since general video and audio format conversion tools are specialized, ordinary users often have higher thresholds for using these tools, so the first implementation is more Complex; when the website meets the format requirements of different user equipments for audio and video files, it requires a higher operating cost to network The network video resources are converted into a format suitable for a specific user equipment, and there are many types of user equipment, which is difficult to meet the requirements of all user equipment. Summary of the invention

In order to meet the format requirements of various user equipments for audio and video files, and to eliminate the format obstacles in downloading audio and video files, and to simplify user operations, embodiments of the present invention provide a method and apparatus for downloading video and audio files. The technical solution is as follows:

In one aspect, a method for downloading a video file is provided, where the method includes: downloading each segment of a video file selected by a user, and performing structural analysis on each downloaded segment;

It is judged according to the analysis result whether each of the segments satisfies the format conversion condition; when the segment satisfies the format conversion condition, the format of the segment is converted into a format that matches the specified device.

The performing structural analysis on each of the downloaded segments specifically includes: identifying a file type of the video file according to each segment, and parsing the segment according to a structure corresponding to the identified file type, to obtain the The structural information of each segment takes the structural information of each segment as the analysis result of each segment.

And determining, according to the analysis result, whether each of the segments satisfies a format conversion condition, and specifically includes:

Determining, according to the structural information of each of the segments, whether the index data of the file header and the file end of the video file is successfully downloaded, and determining, according to the index data of the file header and the file end, whether each segment is a current to-be-converted segment;

If the index data of the file header and the file end of the video file is successfully downloaded, and the segment is determined to be the current to-be-converted segment according to the index data of the file header and the file end, the segment is determined to satisfy the format conversion condition; otherwise , determining that the segment does not satisfy the format conversion bar Piece

Correspondingly, after determining that the segment does not satisfy the format conversion condition, the method further includes: buffering the segment that does not satisfy the format conversion condition until the format conversion condition is satisfied.

Before converting the format of the segment to a format that matches the specified device, the method further includes:

Determining a transcoding parameter that matches the specified device;

Correspondingly, the converting the format of the fragment into a format that matches the specified device includes:

And separating the audio and video streams to obtain an audio data stream and a video data stream; and decoding the audio data stream and the video data stream to obtain an uncompressed audio data stream and an uncompressed video data stream;

And compressing the uncompressed audio data stream and the uncompressed video data stream according to a transcoding parameter matched with the specified device to obtain a compressed audio data stream and a compressed video data stream; and the compressed audio data stream and the compressed video The data streams are combined to obtain a video file having a format matching the specified device.

The determining the transcoding parameters that match the specified device specifically includes:

Prompting the user to select a device model of the specified device, searching for a transcoding parameter matching the specified device in a pre-stored parameter database according to the device model selected by the user; or prompting the user to set a transcoding parameter, and the user is The set transcoding parameter is determined to be a transcoding parameter that matches the specified device.

In another aspect, a device for downloading a video file is provided, where the device includes: a downloading module, configured to download each segment of a video file selected by a user;

An analysis module, configured to perform structural analysis on each segment downloaded by the download module, and a determining module, configured to respectively determine each segment according to an analysis result of the analysis module Whether the format conversion condition is satisfied;

And a conversion module, configured to: when the determining module determines that the segment satisfies a format conversion condition, convert the format of the segment into a format that matches a specified device.

The analyzing module is specifically configured to identify a file type of the video file according to each segment, and parse each segment according to a structure corresponding to the identified file type, to obtain structural information of each segment. The structural information of each of the segments is taken as the analysis result of each of the segments.

The determining module is configured to determine, according to the structural information of each segment, whether the index data of the file header and the file tail of the video file are successfully downloaded, and determine the foregoing according to the index data of the file header and the file tail. Whether the fragment is the current to-be-converted segment; if the file header of the video file is successfully downloaded, and the segment is determined to be the current to-be-converted segment according to the index data of the file header and the file end, determining that the segment satisfies the format conversion condition ; Nobe ' J , judge that the fragment does not satisfy the format conversion condition;

Correspondingly, the device further includes:

And a buffering module, configured to: when the determining module determines that the segment does not satisfy the format conversion condition, cache the segment that does not satisfy the format conversion condition until the format conversion condition is met.

Further, the device further includes:

a determining module, configured to determine a transcoding parameter that matches the specified device before the converting module converts a format of each of the segments into a format that matches the specified device;

Correspondingly, the converting module specifically includes:

And an audio and video stream separation unit, configured to separate the audio and video streams, to obtain an audio data stream and a video data stream;

a decoding unit, configured to decode the audio data stream and the video data stream separated by the audio and video stream separation unit, to obtain an uncompressed audio data stream and an uncompressed video data stream; a coding unit, the uncompressed audio data stream obtained by decoding the decoding unit and the uncompressed video data stream are encoded according to the transcoding parameters determined by the determining module and matched with the designated device, to obtain a compressed audio data stream. And compressing the video data stream;

And an audio/video stream merging unit, configured to combine the compressed audio data stream and the compressed video data stream obtained by the coding unit to obtain a video file with a format matching the specified device.

The determining module is specifically configured to prompt the user to select a device model of the specified device, and search for a transcoding parameter matching the specified device in the pre-stored parameter database according to the device model selected by the user; or, prompt the user to set Transcoding parameters, the transcoding parameters set by the user are determined as transcoding parameters that match the specified device.

The beneficial effects of the technical solutions provided by the embodiments of the present invention are:

By downloading the audio and video files and simultaneously converting them, the downloaded video files can meet the format requirements of various user equipments for the audio and video files, thereby eliminating the format obstacles in downloading the audio and video files, and since no additional download format is required. The conversion tool is thus able to streamline user operations. BRIEF DESCRIPTION OF THE DRAWINGS

1 is a flowchart of a method for downloading a video file according to Embodiment 1 of the present invention; FIG. 2 is a flowchart of a method for downloading a video file according to Embodiment 2 of the present invention; FIG. 3 is a parameter setting of transcoding provided by Embodiment 2 of the present invention; Schematic diagram

4 is a schematic structural diagram of an apparatus for downloading video and audio files according to Embodiment 3 of the present invention; FIG. 5 is a schematic structural diagram of another apparatus for downloading video and audio files according to Embodiment 3 of the present invention;

6 is a schematic structural diagram of another apparatus for downloading video and audio files according to Embodiment 3 of the present invention; Figure 结构 is a schematic structural diagram of a conversion module provided in Embodiment 3 of the present invention. The embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

Embodiment 1

Referring to FIG. 1, the embodiment provides a method for downloading a video file, and the method is specifically as follows:

101: download each segment of the video file selected by the user, and perform structural analysis on each segment;

102: Determine, according to the analysis result, whether each segment satisfies a format conversion condition;

103: When each segment satisfies the format conversion condition, the format of each segment is converted into a format that matches the specified device.

The method for downloading video and audio files provided by this embodiment is to perform format conversion on the user equipment when the user equipment downloads the video file, so that the downloaded video file satisfies the format requirement of the user equipment for the video file, thereby eliminating the existence of downloading the video file. The format is cumbersome, and since there is no need to download a separate format conversion tool, the user operation can be managed.

Embodiment 2

The embodiment provides a method for downloading a video file. After downloading each segment of the video file, the method directly converts the format of each segment into a format that matches the specified device, thereby eliminating the existence of the video file. Format barrier. Referring to FIG. 2, the flow of downloading the audio and video file provided in this embodiment is as follows:

201: download each segment of the video file selected by the user, and perform structural analysis on each segment;

For this step, in order to download the video file desired by the user, the video and audio provided by this embodiment The downloading method of the file may provide the user with an entrance for searching for the audio and video resources, and the user searches for and selects the video and audio file to be downloaded through the entrance of the searched audio and video resource, and starts downloading the video and audio file after adding the downloading task according to the user's selection. In this embodiment, the specific download mode is not limited. Since the existing download mode generally adopts P2P (Peer-to-Peer) technology, the video file is sliced when downloaded, for example, the basic unit is 512 KB. The audio and video files are segmented, and are not downloaded in strict accordance with the segment sequence of the video file segmentation, but the segments of the video file are downloaded in an out-of-order manner.

After downloading the various segments of the video file, in order to successfully convert the format, a structural analysis of each segment is required. When performing structural analysis, the file type of the video file may be identified according to each segment, and each segment is parsed according to the structure corresponding to the identified file type, and the structural information of each segment is obtained, and the structural information of each segment is Analysis results.

Regarding how to identify the file type of the video file according to each segment, this embodiment is not specifically limited. This can be identified by the file suffix name or file type identification byte of each fragment. For example, the three file type identification bytes of the rmvb type file at the beginning of the file are the characters "RMF".

When each segment is parsed according to the structure corresponding to the identified file type, the structure of the segment can be parsed according to the file structure specification corresponding to the file type of the video file. Video files of different file types correspond to different structures. The structure of a general video file includes three parts: description information (HEAD) of the file header, audio and video data (DATA) in the file, and index data (INDX) at the end of the file. The file header describes the overall information of the file, including but not limited to the file duration, the number of audio streams in the file, the detailed information of the audio and video streams, etc.; the index data at the end of the file describes the location information of the file data block, such as the Nth The file address corresponding to the fragment, and so on. The description information of the file header and the index data at the end of the file are generally short. For example, the RMVB file has about 512 KB of head and tail data. By solving the structure of each fragment Analysis, you can determine whether the various parts of the video file have been downloaded.

202: Determine, according to the analysis result, whether each segment satisfies the format conversion condition, if not, execute step 203, otherwise, perform step 204;

Specifically, since each segment of the video file is downloaded in an out-of-order manner, the format conversion needs to be converted according to the order in which the segments are arranged in the video file, that is, the first segment of the video file needs to be converted. Even if other clips have already been downloaded, if the first clip has not been successfully downloaded to the local, it still needs to wait until the first clip is downloaded and the first clip is formatted before the other clips can be sequentially processed. Format conversion. Therefore, when performing format conversion on each segment, it is necessary to ensure that each segment to be format converted is the current segment to be converted.

The determination of the currently to-be-converted segments is in a certain order. Although the segments are downloaded out of order, since the file header describes the file duration and the detailed information of the audio stream in the file, the index data at the end of the file describes the file segment. The position information, so the order of each segment in the video file can be obtained according to the index data of the file header and the file end. According to the order of each segment in the video file, it can be determined that each segment to be format converted is sequentially Whether it is the current segment to be converted.

That is to say, the format conversion condition requires that the index data of the file header and the file end of the video file be downloaded successfully, and it is also required to determine, according to the index data of the file header and the file end, that the fragment to be format converted is the current to-be-converted segment. Then, according to the analysis result, whether each segment satisfies the format conversion condition, firstly, according to the structure information of each segment, it is determined whether the file header and the file end index data of the video file are successfully downloaded, and according to the index data of the file header and the file tail. Determining whether each segment to be format-converted is the current segment to be converted; if the index data of the file header and the file end of the video file is successfully downloaded, and determining the format conversion to be performed according to the index data of the file header and the file tail The segments are sequentially the segments to be converted, and then each segment is judged to satisfy the format conversion condition; otherwise, each segment is judged. The format conversion condition is not met.

Taking the currently downloaded segment as the fifth segment of the video file, if it is determined according to the structure information of each segment downloaded, the index data of the file header and the file end of the video file has not been successfully downloaded, which means that each of the out-of-order downloads is downloaded. The order of the fragments has not been determined, so that all the downloaded fragments do not satisfy the format conversion condition; in addition, even if it is judged that the index data of the file header and the file end of the video file are successfully downloaded, if the format to be converted is That is, the current to-be-converted segment is the fourth segment, that is, the fourth segment has not been successfully formatted, and it is still determined that the fifth segment to be format-converted does not satisfy the format conversion condition; only when the file header of the video file is determined The index data at the end of the file is successfully downloaded, and the fourth segment has been successfully formatted, and the current segment to be converted is just the fifth segment, and it can be judged that the fifth segment satisfies the format conversion condition.

203: Cache the fragment that does not meet the format conversion condition, and after the format conversion condition is met, perform step 204;

For this step, if the current segment does not satisfy the conversion condition, it needs to be cached until the format conversion condition is satisfied, that is, when the current to-be-converted segment is sequentially selected as the segment, and then the format conversion is continued, thereby continuing to perform the subsequent step 204. . For example, if the current segment to be converted is the fifth segment in the video file, if the sixth segment has been downloaded after the fifth segment is not successfully downloaded, the sixth segment needs to be cached because it is not the current segment to be converted. After the 5th fragment is downloaded and the 5th fragment is successfully formatted, the 6th fragment satisfies the format conversion condition.

204: Convert the format of the fragment that satisfies the format conversion condition to a format that matches the specified device.

Specifically, in order to convert the format of the segment into a format that matches the specified device, the method for downloading the video file provided in this embodiment needs to determine a transcoding parameter that matches the specified device before performing the format conversion operation. In the specific implementation, different types of devices can be pre-stored. Corresponding transcoding parameters, and storing the transcoding parameters corresponding to different types of devices in the form of a parameter database, prompting the user to select the device model of the specified device, and searching for the device in the pre-stored parameter database according to the device model selected by the user. Specifies the transcoding parameters that the device matches. Taking the transcoding parameter setting selection interface shown in FIG. 3 as an example, the user is prompted to select the device on which the video file is desired to be downloaded. Find the corresponding transcoding parameters in the parameter database according to the device model entered by the user. The transcoding parameters include, but are not limited to, the file type of the transcoded output, the video resolution, the video frame rate, the video encoding type, the audio encoding type, the video bit rate, and the audio bit rate. The specific content of the transcoding parameter is not performed in this embodiment. limited. Still taking the transcoding parameter shown in Figure 3 as an example, the file type in the transcoding parameter is MP4, video resolution 640x360, video frame rate 15fps, video encoding type MPEG4, audio encoding type AAC, video bit rate 768kbps, and audio code. Rate 64kbps and so on.

If the transcoding parameters corresponding to different types of devices are not stored in advance, the user may be prompted to set a transcoding parameter, and the transcoding parameter set by the user is determined as a transcoding parameter that matches the specified device, that is, the user manually performs transcoding. The setting of the parameters.

In addition to the above two methods for determining the transcoding parameters, other methods may be selected, which are not specifically limited in this embodiment. After determining the transcoding parameters that match the specified device, and converting the format of each segment to a format that matches the specified device, specifically:

The audio and video streams are separated in turn to obtain an audio data stream and a video data stream; and the audio data stream and the video data stream are decoded to obtain an uncompressed audio data stream and an uncompressed video data stream;

Encoding the uncompressed audio data stream and the uncompressed video data stream according to a transcoding parameter matching the specified device to obtain a compressed audio data stream and a compressed video data stream;

The compressed audio data stream and the compressed video data stream are combined to obtain a video file whose format matches the specified device.

Since audio and video streams are separated, decoded, encoded, and combined, they are implemented in the prior art. The embodiment is not specifically limited, and will not be described again. After the compressed audio and video data streams are combined to obtain a video file whose format matches the specified device, the designated device can directly play the video file without having to download the format conversion tool, thereby enabling the user to operate.

It should be noted that the method for downloading a video file provided by this embodiment may perform format conversion on all segments sequentially or simultaneously after all segments of the video file are downloaded. However, in order to save time, the method for downloading the video file provided by the embodiment may not require the format conversion to be converted according to the order of the segments in the video file, that is, each time a segment is downloaded, the segment successfully downloaded is separately executed. The format conversion does not need to wait for all the segments of the video file to be downloaded and then format conversion. Other conversion strategies can also be adopted. This embodiment does not limit the specific conversion strategy.

The method for downloading a video file provided by the embodiment, by downloading the video file at the same time, and simultaneously converting the video file, so that the downloaded video file satisfies the format requirements of the audio and video files of various devices, thereby eliminating the existence of the video file when downloading the video file. The format is cumbersome, and since there is no need to download a separate format conversion tool, the user operation can be managed.

Embodiment 3

Referring to FIG. 4, the embodiment provides a downloading device for video and audio files, and the device includes: a downloading module 401, configured to download each segment of a video file selected by a user; and an analyzing module 402, configured to download the downloading module 401. The segment is subjected to structural analysis; the determining module 403 is configured to determine, according to the analysis result of the analyzing module 402, whether each segment satisfies a format conversion condition;

The conversion module 404 is configured to convert the format of each segment into a format that matches the specified device when the determining module 403 determines that each segment satisfies the format conversion condition.

The analyzing module 402 is specifically configured to identify a file type of the audio and video file according to each segment, and parse each segment according to the structure corresponding to the identified file type, to obtain structural information of each segment, and to construct structure information of each segment. As a result of the analysis. The determining module 403 is specifically configured to determine, according to the structure information of each segment, whether the file header and the file end of the video file are successfully downloaded, and determine whether each segment is the current to be converted according to the index data of the file header and the file tail. If the index data of the file header and the file end of the video file is successfully downloaded, and each segment is judged to be the currently to be converted according to the index data of the file header and the file end, it is judged that each segment satisfies the format conversion condition; otherwise, each judgment is judged; Segments do not satisfy the format conversion condition;

Accordingly, referring to Figure 6, the device further includes:

The cache module 405 is configured to: when the determining module 403 determines that each segment does not satisfy the format conversion condition, cache the segment that does not satisfy the format conversion condition until the format conversion condition is satisfied.

Further, referring to FIG. 7, the apparatus further includes:

a determining module 406, configured to determine, after the converting module 404 converts the format of each segment into a format that matches the specified device, determining a transcoding parameter that matches the specified device;

Correspondingly, the conversion module 404 specifically includes:

The audio and video stream separation unit 404a is configured to separate each segment into an audio and video stream to obtain an audio data stream and a video data stream;

The decoding unit 404b is configured to decode the audio data stream and the video data stream separated by the audio-video stream separation unit 404a to obtain an uncompressed audio data stream and an uncompressed video data stream. The encoding unit 404c is configured to decode the decoding unit 404b. The uncompressed audio data stream and the uncompressed video data stream are encoded according to a transcoding parameter determined by the determining module and matched with the specified device, to obtain a compressed audio data stream and a compressed video data stream;

The audio and video stream merging unit 404d is configured to combine the compressed audio data stream and the compressed video data stream obtained by the encoding unit 404c to obtain a video file whose format matches the specified device.

It should be noted that in order to save time, various segments of the audio and video files can be simultaneously entered. For the line format conversion, the apparatus provided in this embodiment may include multiple conversion modules 404, or one conversion module 404 may include multiple decoding units 404b and coding units 404c, or may adopt other manners. limited.

The determining module 406 is specifically configured to prompt the user to select a device model of the specified device, and search for a transcoding parameter matching the specified device in the pre-stored parameter database according to the device model selected by the user; or, prompt the user to set the transcoding parameter. , the user-set transcoding parameter is determined as a transcoding parameter that matches the specified device.

In summary, the downloading device for video and audio files provided by this embodiment eliminates the download by satisfying the format requirements of the audio and video files of various devices by downloading the video files at the same time. The format barrier exists in video files, and since there is no need to download a separate format conversion tool, user operations can be managed.

It should be noted that, when downloading a video file, the downloading device of the audio and video file in the foregoing embodiment is only illustrated by the division of each functional module. In actual applications, the function may be assigned to different functional modules according to needs. Upon completion, the internal structure of the device is divided into different functional modules to perform all or part of the functions described above. In addition, the downloading device of the audio-visual file provided by the foregoing embodiment is the same as the embodiment of the method for downloading the audio-visual file. For the specific implementation process, refer to the method embodiment, and details are not described herein again.

The serial numbers of the embodiments of the present invention are merely for the description, and do not represent the advantages and disadvantages of the embodiments.

All or part of the steps in the embodiment of the present invention may be implemented by software, and the corresponding software program may be stored in a readable storage medium such as an optical disk or a hard disk.

The above is only the preferred embodiment of the present invention, and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., which are within the spirit and scope of the present invention, should be included in the protection of the present invention. Within the scope.

Claims

Claim

A method for downloading a video file, the method comprising: downloading each segment of a video file selected by a user, and performing structural analysis on each downloaded segment;

The method according to claim 1, wherein the performing structural analysis on each of the downloaded segments comprises:

Identifying a file type of the video file according to each segment, and parsing each segment according to a structure corresponding to the identified file type, obtaining structural information of each segment, and using the structure information of each segment as The analysis results of each fragment.

The method according to claim 2, wherein the determining, according to the analysis result, whether each of the segments satisfies a format conversion condition, specifically includes:

If the index data of the file header and the file end of the video file is successfully downloaded, and the segment is determined to be the current to-be-converted segment according to the index data of the file header and the file end, the segment is determined to satisfy the format conversion condition; otherwise , determining that the segment does not satisfy the format conversion condition;

4. The method according to claim 1, wherein said said segment Before the format is converted to a format that matches the specified device, it also includes:

Determining a transcoding parameter that matches the specified device;

The method according to claim 4, wherein the determining the transcoding parameter that matches the specified device comprises:

6. A device for downloading audio and video files, the device comprising: a downloading module, configured to download each segment of a video file selected by a user;

An analysis module, configured to perform structural analysis on each segment downloaded by the downloading module, and a determining module, configured to determine, according to the analysis result of the analyzing module, whether each of the segments meets a format conversion condition;

7. The apparatus according to claim 6, wherein the analysis module is specific And identifying a file type of the video file according to each segment, and parsing each segment according to a structure corresponding to the identified file type, obtaining structural information of each segment, and constructing the structure of each segment Information is used as the analysis result of each of the segments.

The device according to claim 7, wherein the determining module is configured to determine, according to structural information of each segment, whether the index data of the file header and the file tail of the video file is successfully downloaded, and Determining, according to the index data of the file header and the file end, whether each of the segments is a current to-be-converted segment; if the index data of the file header and the file tail of the video file is successfully downloaded, and according to the file header and the file tail The index data determines that the segment is the current to-be-converted segment, and then determines that the segment satisfies the format conversion condition; otherwise, determines that the segment does not satisfy the format conversion condition;

Correspondingly, the device further includes:

The cache module is configured to: when the determining module determines that the segment does not satisfy the format conversion condition, cache the segment that does not satisfy the format conversion condition until the format conversion condition is met.

The device according to claim 6, wherein the device further comprises: a determining module, configured to: before the converting module converts a format of each segment into a format that matches a specified device, Determining a transcoding parameter that matches the specified device;

Correspondingly, the converting module specifically includes:

a decoding unit, configured to decode the audio data stream and the video data stream separated by the audio and video stream separation unit, to obtain an uncompressed audio data stream and an uncompressed video data stream;

a coding unit, the uncompressed audio data stream obtained by decoding the decoding unit and the uncompressed video data stream are encoded according to the transcoding parameters determined by the determining module and matched with the designated device, to obtain a compressed audio data stream. And compressing the video data stream; And an audio/video stream merging unit, configured to combine the compressed audio data stream and the compressed video data stream obtained by the coding unit to obtain a video file with a format matching the specified device.

The device according to claim 9, wherein the determining module is specifically configured to prompt the user to select a device model of the designated device, and search for a location in the pre-stored parameter database according to the device model selected by the user. Deriving a transcoding parameter that matches the specified device; or, prompting the user to set a transcoding parameter, and determining the transcoding parameter set by the user as a transcoding parameter that matches the specified device.