On 8/28/15, Kevin Wheatley <kevin.j.wheat...@gmail.com> wrote: > HI, > > I was wondering what others think about the option of extending the > OpenEXR reader's gamma option to also include various transfer > characteristic curves, potentially corresponding to the various > AVCOL_TRC_* options, though I don't immediately have a need for all of > them. > > In addition I could see the need for other curves like those of cinema > camera vendor log curves, for instance Red, Sony, ARRI. > > From a user point of view I'd see a command line option specific to > the EXR codec that would take a subset of the colour_trc options > (bt709, etc) extended to include some camera transfer curves and it > would apply the appropriate function prior to the encoding as > AV_PIX_FMT_RGB48/64 as is done currently. > > I'm thinking the command line option would be called 'apply_trc' or > something similar. > > Why it is needed is simply that the gamma function isn't really > sufficient for matching all the typical formats we see in production > use. > > What would be nice would be to embed more colour adjustments prior to > the truncation to integer values but that could be quite complex and > may be better handled outside of ffmpeg. > > I've seen that there was a mention of something similar in the list > archive, but could not find anything other than those emails. > > I'd be great full if any of the devs could comment on the idea before > I start on the implementation. >
Feel free to do it. Note however that those various curves really belong to avfilter once swscale supports float pixel format and exr decoder make use of it. > Thanks > > Kevin > _______________________________________________ > ffmpeg-devel mailing list > ffmpeg-devel@ffmpeg.org > http://ffmpeg.org/mailman/listinfo/ffmpeg-devel > _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
