[FFmpeg-user] Framemd5s of file before and after transcode in the one command line

[Dave Rice]

> On Aug 5, 2015, at 11:18 AM, Peter B. <pb at das-werkstatt.com> wrote:
> 
> On 08/05/2015 03:34 PM, Kieran O'Leary wrote:
>> Here was my command line:
>> 
>> ffmpeg -i Sequence.01.mov -f framemd5 Sequence.01.framemd5 -c:v h264 -c:a copy Sequence.01.mkv -f framemd5 Sequence.01h264.framemd5
>> 
>> It produced identical framemd5s. Is it possible to get ffmpeg to produce a framemd5 of the output file as well?
> 
> I'm not sure if it's possible in a single step (as you're trying to do).
> As far as I know, ffmpeg generates all output from the given source
> (Sequence.01.mov) - not from intermediate-output you created in that
> step (Sequence.01.mkv)
> 
> I guess you might have to generate the output framemd5 separately
> afterwards.
> 
> Maybe others here know better?

Yes, you'd need 2 steps. In your example both framemd5 outputs are based on the same data input. To get framemd5 of both the input and the output you would need two steps:

ffmpeg -i Sequence.01.mov -f framemd5 Sequence.01.framemd5 -c:v h264 -c:a copy Sequence.01.mkv
ffmpeg -i Sequence.01.mkv -f framemd5 Sequence.01h264.framemd5

Dave Rice