[FFmpeg-user] Introduction and problem with decoding DCP (jpeg2000 wrapped in MXF)

[Dave Rice]

Hi Carles,

> On Oct 24, 2014, at 7:25 AM, Carles Vila <cvilad at gmail.com> wrote:
> 
> Hi!
> Mitch, Thanks for taking the time and do the test. This confirms the
> problem is on my side.
> And Carl Eugen, thanks for knowing what I'm talking about!
> I installed ffmpeg one week ago on my mac via homebrew, using this command:
> 
> brew install ffmpeg --with-fdk-aac --with-ffplay --with-freetype
> --with-frei0r --with-libass --with-libvo-aacenc --with-libvorbis
> --with-libvpx --with-opencore-amr --with-openjpeg --with-opus
> --with-rtmpdump --with-schroedinger --with-speex --with-theora --with-tools
> 
> So, in theory nothing would be disabled. Should I compile ffmpeg in some
> other way?

When homebrew builds ffmpeg with openjpeg it disables jpeg2000 (see this commit: https://github.com/Homebrew/homebrew/commit/66a7aa83fdba702a7981744a3db564fc3b953297). This was done because as the commit note says the jpeg2000 encoder/decoder "mostly doesn't work".

To build an ffmpeg as Carl suggests, run `brew edit ffmpeg`, and delete this line `args << "--disable-decoder=jpeg2000"`.
Dave Rice

> Thank you
> 
> On 24 October 2014 12:59, Carl Eugen Hoyos <cehoyos at ag.or.at> wrote:
> 
>> Carles Vila <cvilad <at> gmail.com> writes:
>> 
>>> --enable-libopenjpeg
>> 
>>> --disable-decoder=jpeg2000
>> 
>> I know why you are doing this (and I recommended it often)
>> but it makes detection of xyz impossible.
>> 
>> We should probably work on this but I suspect the easiest
>> solution is to compile without "--disable-encoder" and
>> specify the decoder you want:
>> $ ffmpeg -vcodec libopenjpeg -i input.mxf
>> This will use the internal decoder only to decide the
>> pix_fmt but will use the (bitexact!) libopenjpeg
>> decoder for actual decoding.
>> 
>> Carl Eugen
>> 
>> _______________________________________________
>> ffmpeg-user mailing list
>> ffmpeg-user at ffmpeg.org
>> http://ffmpeg.org/mailman/listinfo/ffmpeg-user
>> 
> _______________________________________________
> ffmpeg-user mailing list
> ffmpeg-user at ffmpeg.org
> http://ffmpeg.org/mailman/listinfo/ffmpeg-user