[FFmpeg-user] decoding jpeg2000 problem

[Carles Vila]

Hi all,
I've run into a problem when converting a j2c image sequence to ProRes. The
dark levels look horrible, especially dark gradients, which seem like
posterized. The bright levels seem to look better.
I think it's a problem related to 12 bit to 10 bit conversion. Is there
anything I can do to make it look better?

Here you can download a short segment (30 MB) of j2c frames and the
resulting Prores: http://we.tl/OGbZBVydwO

And here is my command line, which I have used in the past with perfect
results. Thank you!


ffmpeg -r 24 -i
MAGGIE_FTR-6_S_EN-XX_US_51_2K_IND_20150224_FKI_OV_01/frm_%6d.j2c -c:v
prores -profile:v 3 -r 24 OUTPUT.mov
ffmpeg version 2.4.2 Copyright (c) 2000-2014 the FFmpeg developers
  built on Oct 28 2014 17:39:46 with Apple LLVM version 5.1
(clang-503.0.40) (based on LLVM 3.4svn)
  configuration: --prefix=/usr/local/Cellar/ffmpeg/2.4.2 --enable-shared
--enable-pthreads --enable-gpl --enable-version3 --enable-nonfree
--enable-hardcoded-tables --enable-avresample --enable-vda --cc=clang
--host-cflags= --host-ldflags= --enable-libx264 --enable-libfaac
--enable-libmp3lame --enable-libxvid --enable-libfreetype
--enable-libtheora --enable-libvorbis --enable-libvpx --enable-librtmp
--enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libvo-aacenc
--enable-libass --enable-ffplay --enable-libspeex --enable-libschroedinger
--enable-libfdk-aac --enable-libopus --enable-frei0r --enable-libopenjpeg
--extra-cflags='-I/usr/local/Cellar/openjpeg/1.5.1_1/include/openjpeg-1.5 '
  libavutil      54.  7.100 / 54.  7.100
  libavcodec     56.  1.100 / 56.  1.100
  libavformat    56.  4.101 / 56.  4.101
  libavdevice    56.  0.100 / 56.  0.100
  libavfilter     5.  1.100 /  5.  1.100
  libavresample   2.  1.  0 /  2.  1.  0
  libswscale      3.  0.100 /  3.  0.100
  libswresample   1.  1.100 /  1.  1.100
  libpostproc    53.  0.100 / 53.  0.100
Input #0, image2, from
'MAGGIE_FTR-6_S_EN-XX_US_51_2K_IND_20150224_FKI_OV_01/frm_%6d.j2c':
  Duration: 00:15:16.16, start: 0.000000, bitrate: N/A
    Stream #0:0: Video: jpeg2000 (JPEG 2000 digital cinema 2K), xyz12le,
2048x858, 25 fps, 25 tbr, 25 tbn, 25 tbc
Output #0, mov, to 'OUTPUT.mov':
  Metadata:
    encoder         : Lavf56.4.101
    Stream #0:0: Video: prores (apch) (apch / 0x68637061), yuv422p10le,
2048x858, q=2-31, 200 kb/s, 24 fps, 12288 tbn, 24 tbc
    Metadata:
      encoder         : Lavc56.1.100 prores
Stream mapping:
  Stream #0:0 -> #0:0 (jpeg2000 (native) -> prores (native))
Press [q] to stop, [?] for help
frame=  147 fps= 14 q=0.0 Lsize=   55877kB time=00:00:06.12
bitrate=74733.3kbits/s
video:55875kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB
muxing overhead: 0.002896%