[FFmpeg-devel] [PATCH v3 3/3] avformat/mxfenc: prefer to use the existing metadata

[Tobias Rapp]

On 08.01.2021 11:01, lance.lmwang at gmail.com wrote:
> On Fri, Jan 08, 2021 at 09:09:34AM +0100, Tobias Rapp wrote:
>> On 08.01.2021 07:32, lance.lmwang at gmail.com wrote:
>>> From: Limin Wang <lance.lmwang at gmail.com>
>>>
>>> Please check metadata with below command:
>>> ./ffmpeg -i ../fate-suite/mxf/Sony-00001.mxf -c:v copy -c:a copy out.mxf
>>> ./ffmpeg -i out.mxf
>>>
>>>       company_name    : FFmpeg
>>>       product_name    : OP1a Muxer
>>>       product_version : 58.65.101o
>>>       =>
>>>       company_name    : SONY
>>>       product_name    : eVTR
>>>       product_version : 1.00
>>>
>>> So need to update fate-mxf fate test.
>>>
>>> Signed-off-by: Limin Wang <lance.lmwang at gmail.com>
>>> ---
>>> [...]
>>
>> In my opinion the MXF identification set should contain data about the
>> application that wrote the current version of a file, not some previous file
>> version.
> 
> The example command shows what's change for the fate testing, if you want to
> update to use  your own product version, please use -metadata product_version="xxxxx".

It looks wrong that a MXF file that is muxed by FFmpeg pretends to be 
written by a SONY application. I see that with "-codec copy" you can 
avoid re-encoding of the video and audio streams, and thus might want to 
indicate the A/V encoder software info somewhere separate from the 
container format writer software. But this patch overrides both information.

Regards,
Tobias