CN106021565A

CN106021565A - Method for continuing writing MXF files in Op1a format and Op1b format

Info

Publication number: CN106021565A
Application number: CN201610376225.6A
Authority: CN
Inventors: 侯小叶; 张金沙; 刘盾
Original assignee: Chengdu Sobey Digital Technology Co Ltd
Current assignee: Chengdu Sobey Digital Technology Co Ltd
Priority date: 2016-05-31
Filing date: 2016-05-31
Publication date: 2016-10-12
Anticipated expiration: 2036-05-31
Also published as: CN106021565B

Abstract

The invention discloses a method for continuing writing MXF files in the Op1a format and the Op1b format. The method includes the following steps that whether the MXF files are complete is judged; if the MXF files are not complete, whether header metadata of the MXF files is finished or not is judged, and if the header metadata is not finished, the header metadata is rewritten; the last file body package, containing a complete index table segment, in the MXF files is sought, and audio and video frame numbers which have been written in are obtained by analyzing the file body package; audio and video data continues to be written in and new index table segments are put in, and index information of the audio and video data is recorded; a file tail package is written in; items, with duration parameters needing to be rewritten, in the header metadata are rewritten. Incomplete MXF files are processed by means of the method, and compared with rewriting operation on the incomplete MXF files, processing time is greatly shortened, and workloads are reduced.

Description

The MXF file of Op1a and Op1b form continue method

Technical field

The present invention relates to MXF file and continue technical field, particularly relate to a kind of Op1a and Op1b form MXF file continue method.

Background technology

MXF can process audio frequency and video and the database file of a plurality of track of packing simultaneously, so a complete MXF material content is more, and file is bigger.During the generation of MXF file, if running into power-off or other situations, having no progeny in file write, prior art is all from the beginning to re-write MXF file, the shortcoming that so certainly will have the following aspects:

(1) when rewriteeing MXF file, firstly the need of re-writing Header Metadata(head metadata), head metadata contains the overall content of description main body and the structure of the metadata group of single program fragment, the MXF document knowledge background needing specialty could write correctly, it is therefore desirable to puts into great effort and just can complete；

(2) if needing the MXF file generated very big, write there may come a time when that major part write by file when interrupting, if starting anew write the most again, will certainly waste time and energy,；And, file has been written to interrupt close to during afterbody, at this moment only fraction audio, video data need to be write again, then FPP(tail of file bag is write according still further to MXF standard) and RIP(random index bag), a complete material being available for exchange of media can be become, if rewriteeing this class file nearly equivalent to having write an identical complete file again, this is completely unnecessary；

(3) if rewriteeing MXF file, owing to the description information needed for the difference of different file coding format is different, if being ignorant of the people decoding information needed when writing video/audio and describing information, it is possible to the unclear characterising parameter that have to write, during rewriting, it is likely to result in mistake.

Summary of the invention

It is an object of the invention to overcome the deficiencies in the prior art, there is provided a kind of Op1a and Op1b form MXF file continue method, by the method continued, imperfect MXF file is processed, the rewrite operation of phase comparison imperfect MXF file, substantially reduce the process time, decrease workload.

It is an object of the invention to be achieved through the following technical solutions: the MXF file of Op1a and Op1b form continue method, including: judge that MXF file is the most complete；If described MXF file is imperfect, then judge whether the head metadata of described MXF file completes, if described head metadata is not fully complete, then rewrite described head metadata；Find in MXF file that last comprises complete file body bag indexing table segment, by resolve described file body bag obtain written into audio frequency and video frame number；Continue to write to audio, video data, and fill new index table segment, the index information of video-audio frequency data；Write tail of file bag.

Described method of continuing also includes: rewrite the item needing to rewrite duration parameters in head metadata.

Judge that the method that MXF file is the most complete is: the data at the end reading described MXF file are analyzed, judge whether described MXF file exists random index bag, if there is random index bag in described MXF file, then it is assumed that described MXF file is complete, otherwise it is assumed that described MXF file is imperfect.

If described head metadata completes, then record head metadata needs to rewrite the item side-play amount hereof of duration parameters.

Described head metadata need the item rewriting duration parameters include video and audio sequence and actual source material.

Described method of continuing also includes: judge whether to write complete index table segment and random index bag.

The invention has the beneficial effects as follows:

(1) workload of imperfect MXF file write is reduced: when incomplete MXF file is continued, it is not necessary to re-write head metadata, and the part audio, video data having been written into avoids the need for rewriteeing one time again, it is possible to greatly reduce workload；

(2) shorten imperfect MXF file write time: written into audio, video data need not re-write, save the plenty of time, especially file write-in block for the first time interrupts close to the when of afterbody, continues this class file and compares this class file of rewriting, and advantage is more apparent from；

(3) operability of the write of incomplete MXF file is improved: because decreasing re-writing of head metadata, afterbody is needed to write video presentation information and the MXF file of audio description information, have only to resolve the head metadata information in MXF top of file, replicate and write.

Accompanying drawing explanation

Fig. 1 be the MXF file of Op1a and Op1b form in the present invention continue method.

Detailed description of the invention

Technical scheme is described in further detail below in conjunction with the accompanying drawings, but protection scope of the present invention is not limited to the following stated.

As it is shown in figure 1, the MXF file of Op1a and Op1b form continue method, comprise the following steps:

Step one, judge that MXF file is the most complete: the data at the end reading described MXF file are analyzed, judge whether described MXF file exists random index bag, if there is random index bag in described MXF file, then it is assumed that described MXF file is complete, otherwise it is assumed that described MXF file is imperfect.

If step 2 described MXF file is imperfect, then judge whether the head metadata of described MXF file completes, if described head metadata is not fully complete, then rewrite described head metadata；If described head metadata completes, then record head metadata needs to rewrite the item side-play amount hereof of duration parameters.Need to rewrite the item side-play amount hereof of duration parameters by record, when facilitating follow-up rewriting duration, directly navigate to need the document location of rewrite data according to the side-play amount of record, it is not necessary to again resolve head metadata, saved the time.

If described MXF file is complete, then illustrate that described MXF file is without continuing.

Step 3, All Files body bag (BPP) resolved in MXF file, find in MXF file that last comprises the file body bag completely indexing table segment (Index Table Segment), by resolve described file body bag obtain written into audio frequency and video frame number.

Step 4, continue to write to audio, video data, and fill new index table segment, the index information of video-audio frequency data.

Step 5, write tail of file bag.

Described method of continuing also includes: rewrites the item needing to rewrite duration parameters in head metadata, positions by resolving the video and audio sequence obtained and actual source material side-play amount hereof above, rewrites the time advantage in video and audio sequence and actual source material.

Described method of continuing also includes: judge whether to need to write complete index table segment and random index bag according to the concrete form of file, for needing write complete index table segment and the MXF file of random index bag, is then indexed table segment and the write of random index bag.

The present invention is based on MXF standard packing manner, by resolving physical arrangement and the logical structure of MXF file, it is possible to simple, the quickly realization process to imperfect MXF file, the MXF file after process can correctly be play and transmit.By the method continued, imperfect MXF file is processed, the rewrite operation of phase comparison imperfect MXF file, substantially reduce the process time, decrease workload.

The above is only the preferred embodiment of the present invention, it is to be understood that the present invention is not limited to form disclosed herein, it is not to be taken as the eliminating to other embodiments, and can be used for other combinations various, amendment and environment, and can be modified by above-mentioned teaching or the technology of association area or knowledge in contemplated scope described herein.And the change that those skilled in the art are carried out and change are without departing from the spirit and scope of the present invention, the most all should be in the protection domain of claims of the present invention.

Claims

The MXF file of 1.Op1a and Op1b form continue method, it is characterised in that: including:

Judge that MXF file is the most complete；

If described MXF file is imperfect, then judge whether the head metadata of described MXF file completes, if described head metadata is not fully complete, then rewrite described head metadata；

Find in MXF file that last comprises complete file body bag indexing table segment, by resolve described file body bag obtain written into audio frequency and video frame number；

Continue to write to audio, video data, and fill new index table segment, the index information of video-audio frequency data；

Write tail of file bag.
The MXF file of Op1a and Op1b form the most according to claim 1 continue method, it is characterised in that method of continuing described in: also includes: rewrite in head metadata the item needing to rewrite duration parameters.
The MXF file of Op1a and Op1b form the most according to claim 1 continue method, it is characterized in that: judge that the method that MXF file is the most complete is: the data at the end reading described MXF file are analyzed, judge whether described MXF file exists random index bag, if there is random index bag in described MXF file, then think that described MXF file is complete, otherwise it is assumed that described MXF file is imperfect.
The MXF file of Op1a and Op1b form the most according to claim 1 continue method, it is characterised in that: if described head metadata completes, then record head metadata needs to rewrite the item side-play amount hereof of duration parameters.
5. continue method according to the MXF file of Op1a and the Op1b form described in claim 2 or 4, it is characterised in that: described head metadata need the item rewriting duration parameters include video and audio sequence and actual source material.
The MXF file of Op1a and Op1b form the most according to claim 1 continue method, it is characterised in that method of continuing described in: also includes: judge whether to write complete index table segment and random index bag.