CN109982113B

CN109982113B - Video file processing method and device

Info

Publication number: CN109982113B
Application number: CN201711461989.6A
Authority: CN
Inventors: 崔九洲
Original assignee: Alibaba Group Holding Ltd
Current assignee: Alibaba Group Holding Ltd
Priority date: 2017-12-28
Filing date: 2017-12-28
Publication date: 2022-04-08
Anticipated expiration: 2037-12-28
Also published as: CN109982113A

Abstract

The application discloses a video file processing method and device, comprising the following steps: the server side obtains the trial viewing time; calculating the file position corresponding to the trial viewing duration in the video file according to the obtained trial viewing duration; and when the video data requested by the client is judged to exceed the file position of the calculated corresponding trial viewing time, stopping returning the video data to the client. The playing of the video file is flexibly controlled through the application.

Description

Video file processing method and device

Technical Field

The present application relates to, but not limited to, computer technology, and more particularly, to a method and apparatus for processing a video file.

Background

Currently, file formats for Video on demand include a Flash Video (FLV) format, a multimedia file format using MPEG-4 (MP4, MPEG-4Part 14), a Transport Stream (TS) format, and the like. Among them, MPEG is a Moving Picture Experts Group (Moving Picture Experts Group).

For the purpose of introducing members (VIPs), the website sets some videos as VIP users to be watched, and ordinary users can only try for a few minutes. In the implementation of the trial viewing, a Content Delivery Network (CDN) is required to perform some processing to prevent Content after the trial viewing duration from being returned to the user when the user drags for more than the trial viewing duration.

For both the FLV file and the MP4 file, there is meta (meta) information. Thus, if the trial viewing time is 5 minutes, the position corresponding to the trial viewing time length can be directly located according to the meta information. However, the TS file has no meta information, and if the TS file is returned to the position where the TS file tries for 5 minutes, the TS file can be realized only by analyzing the information of the TS packet.

Disclosure of Invention

In order to solve the above technical problem, the present application provides a video file processing method and apparatus, which can flexibly control the playing of a video file.

In order to achieve the object of the present invention, the present application provides a video file processing method, including: the server side obtains the trial viewing time;

calculating the file position corresponding to the trial viewing duration in the video file according to the obtained trial viewing duration;

and when the video data requested by the client is judged to exceed the file position of the calculated corresponding trial viewing time, stopping returning the video data to the client.

The present application further provides a computer-readable storage medium storing computer-executable instructions for performing any of the video processing methods described above.

The present application further provides an apparatus for implementing video processing, comprising a memory and a processor, wherein the memory stores the following instructions executable by the processor: acquiring the length of the trial viewing time; calculating the file position corresponding to the trial viewing duration in the video file according to the obtained trial viewing duration; and when the video data requested by the client is judged to exceed the file position of the calculated corresponding trial viewing time, stopping returning the video data to the client.

The present application further provides a video processing apparatus, including: an acquisition module, a calculation module and a judgment module, wherein,

the acquisition module is used for acquiring the trial viewing time;

the calculation module is used for calculating the file position corresponding to the trial viewing duration in the video file according to the obtained trial viewing duration;

and the processing module is used for stopping returning the video data to the client when judging that the video data requested by the client exceeds the file position of the calculated corresponding trial viewing duration.

The present application at least includes: the server side obtains the trial viewing time; calculating the file position corresponding to the trial viewing duration in the video file according to the obtained trial viewing duration; and when the video data requested by the client is judged to exceed the file position of the calculated corresponding trial viewing time, stopping returning the video data to the client. The playing of the video file is flexibly controlled through the application. In particular, it is achieved that the user is controlled to stop playing the TS file after playing to a prescribed point in time.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

Drawings

The accompanying drawings are included to provide a further understanding of the claimed subject matter and are incorporated in and constitute a part of this specification, illustrate embodiments of the subject matter and together with the description serve to explain the principles of the subject matter and not to limit the subject matter.

FIG. 1 is a flow chart of a video processing method of the present application;

FIG. 2 is a schematic flowchart of an embodiment of a video processing method according to the present application;

fig. 3 is a schematic diagram of a composition structure of a video processing apparatus according to the present application.

Detailed Description

To make the objects, technical solutions and advantages of the present application more apparent, embodiments of the present application will be described in detail below with reference to the accompanying drawings. It should be noted that the embodiments and features of the embodiments in the present application may be arbitrarily combined with each other without conflict.

In one exemplary configuration of the present application, a computing device includes one or more processors (CPUs), input/output interfaces, a network interface, and memory.

The memory may include forms of volatile memory in a computer readable medium, Random Access Memory (RAM) and/or non-volatile memory, such as Read Only Memory (ROM) or flash memory (flash RAM). Memory is an example of a computer-readable medium.

Computer-readable media, including both non-transitory and non-transitory, removable and non-removable media, may implement information storage by any method or technology. The information may be computer readable instructions, data structures, modules of a program, or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), Static Random Access Memory (SRAM), Dynamic Random Access Memory (DRAM), other types of Random Access Memory (RAM), Read Only Memory (ROM), Electrically Erasable Programmable Read Only Memory (EEPROM), flash memory or other memory technology, compact disc read only memory (CD-ROM), Digital Versatile Discs (DVD) or other optical storage, magnetic cassettes, magnetic tape magnetic disk storage or other magnetic storage devices, or any other non-transmission medium that can be used to store information that can be accessed by a computing device. As defined herein, computer readable media does not include non-transitory computer readable media (transient media), such as modulated data signals and carrier waves.

The steps illustrated in the flow charts of the figures may be performed in a computer system such as a set of computer-executable instructions. Also, while a logical order is shown in the flow diagrams, in some cases, the steps shown or described may be performed in an order different than here.

The TS format is suitable for packaging high-definition formats such as movies and the like, and the video stream can be independently decoded from any segment due to the unique packaging format of the TS format, so that the TS format is widely applied in the video field. If the video website provides a fee service for some videos and provides a test-watching segment for the user, the user needs to be controlled to stop playing after the user plays to a specified time point. However, since the TS file has no meta information, it is conceivable that the TS information is read from the beginning and analyzed until a desired time. On one hand, the processing time is long, and particularly if the trial viewing time is long, the file can be read for a long time to be positioned; on the other hand, bandwidth waste is also caused, server resources are also wasted, and the program always calculates and has certain influence on the CPU and the memory of the server; moreover, since the file content needs to be read repeatedly, a large amount of traffic is required.

In order to realize flexible control on video playing, a video processing method proposed by the inventor of the present application is shown in fig. 1, and includes:

step 100: the server side obtains the trial watching time length.

In this step, the server may obtain the trial viewing duration from the request parameter from the client, and the specific implementation belongs to the known technology of those skilled in the art, and is not used to limit the protection scope of the present application, and is not described here again.

Step 101: and calculating the file position corresponding to the trial viewing time length in the video file according to the obtained trial viewing time length.

The method specifically comprises the following steps:

respectively reading data of a file head and a file tail of a video file such as a TS file, acquiring timestamp information of the video file such as the TS file head and timestamp information of the video file such as the TS file tail, converting the timestamp information into accurate time, and subtracting the accurate time from the accurate time to obtain the total time of the video file such as the TS file;

acquiring the size of a video file such as a TS file;

and calculating the file position corresponding to the trial viewing time length according to the obtained trial viewing time length, the size of the video file such as the TS file and the total time length of the video file such as the TS file.

Optionally, the size of the video file, such as a TS file, may be obtained by sending a hypertext transfer protocol text length (HTTP get content length) request when the server returns to the source, and the specific implementation belongs to the known technology of those skilled in the art, and is not used to limit the protection scope of the present application, and is not described herein again.

Optionally, calculating the file position corresponding to the trial viewing time length includes:

calculating the ratio of the size of the file to the total duration of the file to obtain a bit rate, namely the number of bits transmitted per second; and calculating the product of the bit rate and the trial viewing duration to obtain the file position corresponding to the trial viewing duration.

Optionally, for a video with a dynamic bitrate, the bitrate is not uniformly distributed in the whole video, and after step 101, the method further includes:

and verifying whether the calculated time of the file position corresponding to the trial viewing duration is close to the actually required trial viewing time, wherein the time and the actual required trial viewing time are allowed to have a slight error, namely, are within a preset error range. If the two are beyond the preset error range, a larger time difference exists, and a position information which is closer to the file position corresponding to the actually required trial viewing time is further obtained according to the following formula:

new position information ═ [ (last calculated time-required time)/required time ] + last calculated position;

and performing recursive calculation according to the algorithm to finally find the file position information meeting the preset precision.

Step 102: and when the video data requested by the client is judged to exceed the file position of the calculated corresponding trial viewing time, stopping returning the video data to the client.

Optionally, the server may determine whether the video data requested by the client exceeds the calculated file position according to the video byte interval requested by the client.

Optionally, the server may further return an error message to the client according to the customization of the client to notify the client that the trial viewing is finished.

The following describes the implementation of the method in detail by taking a video file as a TS file as an example.

The TS file is composed of a plurality of Packetized Elementary Stream (PES) packets, each of which is fixed to 188 bytes in size, and video, audio, and other information are stored in the PES packets. One PES packet may include a plurality of TS packets, and the last TS packet is less than 188 bytes padded with 0.

Each PES packet has only one header information, the header information includes time information, but a Presentation Time Stamp (PTS) is read instead of directly reading the time itself, and the final time can be obtained by calculating the PTS, which is specifically implemented as follows:

the TS packet starts with a fixed two bytes 0x47, the PES packet starts with bytes 0x000001, and the header information of the PES starts with bytes 0x 10. Header information of the PES may be read from the TS file by the above information, and the header information includes a PTS flag (PTS flag), and if the PTS flag is 1, it indicates that there is a PTS in the header information. The PTS information is composed of a plurality of bytes, and is stored in five bytes, and the bits [32..30] [29..15] [14..0] in the five bytes. The bits are shifted and combined in the front-back order to form a new integer and then divided by 90000, namely the final time information, and the unit is second. The manner of reading the time of the TS header and the TS trailer is the same as that described above, and is not described herein again. Since the TS file does not necessarily start with 0, the end time (end _ time) minus the start time (begin _ time) is necessarily adopted as the total duration of the video. Then, the bit rate (bitrate) of the video is shown in equation (1):

bitrate＝(end_time–begin_time)/content_length (1)

in formula (1), content _ length is the size of the TS file, and how to obtain the size of the TS file is not used to limit the protection scope of the present application, and is not described herein again.

The file position range _ length corresponding to the trial viewing time length is shown in formula (2):

range_length＝bitrate*range_time (2)

in the formula (2), the range _ time is the trial viewing time.

Alternatively, for a video with a dynamic bitrate, since the bitrate is not uniformly distributed in the whole video, the range _ length calculated by formula (1) and formula (2) is used as the start to calculate the current timestamp current _ time in the manner of shift merging as described above.

For video with average bitrate, current _ time is equal to range _ time, but for video with dynamic bitrate or other cases, these two times may not be equal, and at this time, the calculation needs to be continued to obtain range _ length' corresponding to the actual range _ time.

The range _ length' to be positioned to the next time by the scale is as shown in equation (3):

range_length’

＝range_length-((range_length–bitrate*current_time)/(range_time-current_time))*(range_time-current_time)

＝2*range_length-bitrate*current_time (3)

in this way, by repeating the calculation formula (3) from the newly obtained file position and current _ time, one piece of position information closer to the file position corresponding to the actually required time can be acquired.

It should be noted that, due to the characteristics of the TS file, there may be a reasonable range, for example, a range _ length' with a difference value less than 1 second may be considered as the final location information found.

Fig. 2 is a schematic flowchart of an embodiment of a video processing method according to the present application, as shown in fig. 2, including:

step 200: and respectively reading 1KB data of the TS file head and the TS file tail.

Step 201: and determining whether a TS packet header is found according to byte reading 0x47, if so, determining that the current video file is a TS file, and entering step 202, otherwise, returning to step 201.

Step 202: reading 0x000001 determines whether the PES packet header is found, if so, step 203 is entered, otherwise, step 201 is returned.

Step 203: reading the header information of the PES, judging whether a PTS flag in the header information is 1, if the PTS flag is 1, indicating that the header information has a PTS, and entering step 204; otherwise, the procedure returns to step 201.

Step 204: and reading the PTS and calculating the timestamp information, calculating the total time length of the TS file according to the time difference value of the TS head and the TS tail, and calculating the bit rate of the current video according to the size of the obtained TS file according to the formula (1).

Step 205: and (4) according to the formula (2), calculating the file position corresponding to the trial viewing time length according to the calculated bit rate and the trial viewing time length.

Step 206: reading the current time information from the calculated file position, judging whether the time length is equal to the trial viewing time length or not, and if so, ending the process; if they are not equal or the difference is not within a preset error range, such as 1 second, step 207 is entered.

Step 207: and (4) recalculating the file position corresponding to the trial viewing time length according to the formula (3) and returning to the step 206.

The present application further provides a computer-readable storage medium storing computer-executable instructions for performing any of the above-described video processing methods.

Fig. 3 is a schematic structural diagram of a video processing apparatus according to the present application, as shown in fig. 3, at least including: an acquisition module, a calculation module and a judgment module, wherein,

the acquisition module is used for acquiring the trial viewing time;

Optionally, the calculation module is specifically configured to:

respectively reading the data of the video file header and the data of the video file tail, acquiring the timestamp information of the video file header and the timestamp information of the video file tail, and performing subtraction operation on the two timestamp information to obtain the total duration of the video file;

acquiring the size of the video file;

and calculating the file position corresponding to the trial viewing duration according to the obtained trial viewing duration, the size of the video file and the total duration of the video file.

Optionally, the calculating, by the calculating module, a file position corresponding to the trial viewing time length includes:

calculating the ratio of the size of the video file to the total duration of the video file to obtain a bit rate;

and calculating the product of the obtained bit rate and the trial viewing duration to obtain the file position corresponding to the trial viewing duration.

Optionally, the processing module is further configured to:

and verifying whether the calculated time of the file position corresponding to the trial viewing duration is matched with the required time. If there is a time difference, recalculating a new file location based on the actual time, the requested time and the calculated file location until a file location satisfying a preset accuracy is obtained.

The video processing device can be arranged at a server side.

Although the embodiments disclosed in the present application are described above, the descriptions are only for the convenience of understanding the present application, and are not intended to limit the present application. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the disclosure as defined by the appended claims.

Claims

1. A video file processing method, comprising: the server side obtains the trial viewing time;

respectively reading the data of the video file header and the data of the video file tail, acquiring the timestamp information of the video file header and the timestamp information of the video file tail, converting the timestamp information into accurate time, and subtracting the accurate time to obtain the total duration of the video file;

acquiring the size of the video file;

calculating the file position corresponding to the trial viewing duration according to the obtained trial viewing duration, the size of the video file and the total duration of the video file;

verifying whether the calculated time of the file position corresponding to the trial viewing duration is matched with the required time or not, if so, recalculating a new file position according to the ratio of the time difference to the required time and the calculated file position until the file position meeting the preset precision is obtained;

2. The video file processing method according to claim 1, wherein said calculating the file position corresponding to the trial viewing time period comprises:

3. A computer-readable storage medium storing computer-executable instructions for performing the video processing method of any one of claims 1 to 2.

4. An apparatus for implementing video processing, comprising a memory and a processor, wherein the memory has stored therein the following instructions executable by the processor: acquiring the length of the trial viewing time; respectively reading the data of the video file header and the data of the video file tail, acquiring the timestamp information of the video file header and the timestamp information of the video file tail, converting the timestamp information into accurate time, and subtracting the accurate time to obtain the total duration of the video file; acquiring the size of the video file; calculating the file position corresponding to the trial viewing duration according to the obtained trial viewing duration, the size of the video file and the total duration of the video file; verifying whether the calculated time of the file position corresponding to the trial viewing duration is matched with the required time or not, if so, recalculating a new file position according to the ratio of the time difference to the required time and the calculated file position until the file position meeting the preset precision is obtained; and when the video data requested by the client is judged to exceed the file position of the calculated corresponding trial viewing time, stopping returning the video data to the client.

5. A video processing apparatus, comprising: an acquisition module, a calculation module and a judgment module, wherein,

the acquisition module is used for acquiring the trial viewing time;

the calculation module is used for respectively reading the data of the video file head and the data of the video file tail, acquiring the timestamp information of the video file head and the timestamp information of the video file tail, converting the timestamp information into accurate time, and subtracting the accurate time from the accurate time to obtain the total time of the video file; acquiring the size of the video file; calculating the file position corresponding to the trial viewing duration according to the obtained trial viewing duration, the size of the video file and the total duration of the video file; verifying whether the calculated time of the file position corresponding to the trial viewing duration is matched with the required time or not, if so, recalculating a new file position according to the ratio of the time difference to the required time and the calculated file position until the file position meeting the preset precision is obtained;

6. The video processing apparatus according to claim 5, wherein the calculating of the file position corresponding to the trial viewing time duration in the calculating module comprises: