[FFmpeg-devel] [RFC] avformat/mxfenc: stop encoding if unfilled video packet

[Tobias Rapp]

On 05.10.2015 09:10, tim nicholson wrote:
> On 04/10/15 13:07, Tomas Härdin wrote:
>> On Mon, 2015-09-28 at 15:11 +0200, Tobias Rapp wrote:
>>> [...]
>>
>> For me the most important thing is that anything dealing with MXF should
>> never write invalid files.
>
> +1 for sure.

To overstate your point: So it would be OK to skip most input frames and 
replace them with black frames as long as the output file is valid MXF?

I think there are different requirements for determining what makes an 
"error" depending on the use-case. If I try to recover video frames from 
an broken hard disk, for example, I probably won't mind some lost 
frames. If I try to encode a video file from a presumably healthy input 
file I likely care about lost frames.

>> I'm not sure whether the current code is
>> broken per se, but it does look suspicious. Perhaps someone else has a
>> better idea?
>>
>
> Truncate/pad mis sized frames to allow muxing to continue, and issue a
> warning (as at present)?

It is currently quite difficult to ensure that all frames have been 
transcoded if there is only a warning in the log message because AFAIK 
the only generic way to separate a info log message from a warning is to 
parse terminal color code sequences. The other solution would be to 
maintain a RegEx black-list of log output messages in the parent process.

Wouldn't it be helpful to introduce some flag option like "-flags 
+xerror" on avformat level to toggle between "recover as much as 
possible" mode and "encode all or fail" mode?

Regards,
Tobias