[FFmpeg-user] Can you encode lossless Motion JPEG 2000 videos with ffmpeg using the right command line arguments?

[Paul B Mahol]

On 6/19/12, David Rice <daverice at mac.com> wrote:
>
> On Jun 18, 2012, at 9:17 PM, Gabri Nurtinaz Shally wrote:
>
>> On Jun 19, 2012 8:00 AM, "Shyamal Chandra" <shyamalc at gmail.com> wrote:
>>>
>>> Hi,
>>>
>>> Can you encode lossless Motion JPEG videos with ffmpeg using the right
>>> command line arguments?
>>>
>>> I want to convert an uncompressed AVI into a lossless Motion JPEG 2000.
>>>
>>
>> yes, you can, since mjpeg can be found in "ffmpeg -codecs" output. you
>> can
>> try:
>> ffmpeg -i yourfile.avi -vcodec mjpeg -acodec copy output.mkv
>>
>> FYI, JPEG itself is a lossy format, so overall it is not a lossless
>> video.
>> for me, i'll choose h264 for same bitrate.
>
> Motion JPEG is a lossy codec.
> Motion JPEG 2000 is a container format primarily (or perhaps solely?) for
> containing jpeg2000 encodings.
> jpeg2000 is a codec that could be used in either lossy or lossless modes.
>
> Since you're interested in lossless encoding, I presume you're interested in
> Motion JPEG 2000 and/or jpeg2000. FFmpeg does not support writing Motion
> JPEG 2000 files but can read them. If you need Motion JPEG2000 you could
> look at frames_to_mj2 in http://code.google.com/p/openjpeg/. FFmpeg can
> encode lossless jpeg2000 with either its included, but experimental,
> jpeg2000 codec (listed as 'j2k') or via libopenjpeg if you compile it with
> --enable-libopenjpeg.
> If you compile with openjpeg you could try:
> ffmpeg -i file.avi -map 0 -c:v libopenjpeg -c:a copy lossless.mov
>
> If not, then try:
> ffmpeg -i file.avi -map 0 -c:v j2k -strict experimental -c:a copy
> output.mov
>
> Note that the j2k and libopenjpeg versions of the jpeg2000 encoder support
> different sets of pixel formats. For instance libopenjpeg can encode yuv410p
> but the j2k codec would format this to yuv444p. If your goal is to
> losslessly encode the source video so that both the source and resulting
> lossless file decode to the same pixels then watch ffmpeg's reporting
> closely. You could also use ffmpeg's framemd5 format to make sure that the
> source and lossless version decode to the same values. From the example
> above, these two commands should yield the same result:
> ffmpeg -i file.avi -map 0:v:0 -f framemd5 file.avi.framemd5
> ffmpeg -i output.mov -map 0:v:0 -f framemd5 output.mov.framemd5
>

As already pointed out j2k codec, both encoder and decoder are not lossless nor
bitexact with reference jpeg2000 implementations, which explains why
they are experimental.