Version errors when trying to install open scene graph 3.4.1

Question

I am trying to rebuild open scene graph version 3.4.1 from source, following this, i get the following build error about ffmpeg version:

Building CXX object src/osgPlugins/ffmpeg/CMakeFiles/osgdb_ffmpeg.dir/FFmpegDecoderAudio.o
/home/wrkdir/osg/osg/src/osgPlugins/ffmpeg/FFmpegDecoderAudio.cpp: In member function 'void osgFFmpeg::FFmpegDecoderAudio::open(AVStream*, osgFFmpeg::FFmpegParameters*)':
/home/wrkdir/osg/osg/src/osgPlugins/ffmpeg/FFmpegDecoderAudio.cpp:230:20: error: 'AVCodecContext' {aka 'struct AVCodecContext'} has no member named 'get_buffer'; did you mean 'get_buffer2'?
  230 |         m_context->get_buffer = avcodec_default_get_buffer;
      |                    ^~~~~~~~~~
      |                    get_buffer2
/home/wrkdir/osg/osg/src/osgPlugins/ffmpeg/FFmpegDecoderAudio.cpp:230:33: error: 'avcodec_default_get_buffer' was not declared in this scope; did you mean 'avcodec_default_get_buffer2'?
  230 |         m_context->get_buffer = avcodec_default_get_buffer;
      |                                 ^~~~~~~~~~~~~~~~~~~~~~~~~~
      |                                 avcodec_default_get_buffer2
/home/wrkdir/osg/osg/src/osgPlugins/ffmpeg/FFmpegDecoderAudio.cpp:231:20: error: 'AVCodecContext' {aka 'struct AVCodecContext'} has no member named 'release_buffer'
  231 |         m_context->release_buffer = avcodec_default_release_buffer;
      |                    ^~~~~~~~~~~~~~
/home/wrkdir/osg/osg/src/osgPlugins/ffmpeg/FFmpegDecoderAudio.cpp:231:37: error: 'avcodec_default_release_buffer' was not declared in this scope; did you mean 'avcodec_default_get_buffer2'?
  231 |         m_context->release_buffer = avcodec_default_release_buffer;
      |                                     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      |                                     avcodec_default_get_buffer2

I have tried to look for older version of ffmpeg that would reference avcodec_default_release_buffer in its documentation but couldnt find one, and rebuilt and installed version 3.0 and 2.0, however i get the same building error, has someone had the same building problem before on osg?

Answer 1

The documentation for ffmpeg 2.2 has that function listed as deprecated in the autogenerated function references: https://ffmpeg.org/doxygen/2.2/group__lavc__decoding.html#ga666e4cc55f8a14c3b1ea66aaef2f6970

It may have been removed since then. You could go back to 2.2 to access it again.

The commit notes say: 80e9e63 / 759001c - add the refcounted_frames field to AVCodecContext to make audio and video decoders return reference-counted frames. Add get_buffer2() callback to AVCodecContext which allocates reference-counted frames. Add avcodec_default_get_buffer2() as the default get_buffer2() implementation. Deprecate AVCodecContext.get_buffer() / release_buffer() / reget_buffer(), avcodec_default_get_buffer(), avcodec_default_reget_buffer(), avcodec_default_release_buffer(). Remove avcodec_default_free_buffers(), which should not have ever been called from outside of lavc. Deprecate the following AVFrame fields: * base -- is now stored in AVBufferRef * reference, type, buffer_hints -- are unnecessary in the new API * hwaccel_picture_private, owner, thread_opaque -- should not have been accessed from outside of lavc * qscale_table, qstride, qscale_type, mbskip_table, motion_val, mb_type, dct_coeff, ref_index -- mpegvideo-specific tables, which are not exported anymore.

So it looks like you should look at adapting the code to use the get_buffer2 version. If that's outside your ability, get ahold of me and I can see if I can help you.