How do I properly format a request for ffmpeg to decode using a particular codec?

Question

r3d is listed as a supported codec for decoding, however when I attempt to specify the r3d decoder, I get the error message "Unknown decoder". What is the correct manner of specifying a decoder codec?

me$ ffmpeg -c r3d -i one.r3d one.mpg
ffmpeg version 1.2 Copyright (c) 2000-2013 the FFmpeg developers
  built on May  8 2013 19:48:08 with Apple clang version 4.0 (tags/Apple/clang-421.0.57) (based on LLVM 3.1svn)
  configuration: --prefix=/usr/local/Cellar/ffmpeg/1.2 --enable-shared --enable-pthreads --enable-gpl --enable-version3 --enable-nonfree --enable-hardcoded-tables --enable-avresample --enable-vda --cc=cc --host-cflags= --host-ldflags= --enable-libx264 --enable-libfaac --enable-libmp3lame --enable-libxvid
  libavutil      52. 18.100 / 52. 18.100
  libavcodec     54. 92.100 / 54. 92.100
  libavformat    54. 63.104 / 54. 63.104
  libavdevice    54.  3.103 / 54.  3.103
  libavfilter     3. 42.103 /  3. 42.103
  libswscale      2.  2.100 /  2.  2.100
  libswresample   0. 17.102 /  0. 17.102
  libpostproc    52.  2.100 / 52.  2.100
[mp3 @ 0x7fa2e4006600] Format mp3 detected only with low score of 1, misdetection possible!
Unknown decoder 'r3d'

Solution

The problem is that my version of ffmpeg was not compiled with r3d support, so while it did appear under

ffmpeg -formats

it did not appear under

ffmpeg -decoders

Comments

[Kaliatech]

Make sure r3d is a supported decoded in your specific build of ffmpeg using ffmpeg -decoders. Also, googling shows there have been issues with decoding more recent versions of the R3D format. Example: cinematography.com/index.php?showtopic=53575

[timonsku]

Its not a codec its a format. Its a container that uses JPEG2000 encoded frames and pcm audio.