[FFmpeg-user] Questions about readout important metadata from DPX files ("logarthmic/linear") and recreate DPX with same metadata

[Carl Eugen Hoyos]

Christoph Gerstbauer <christophgerstbauer <at> gmail.com> writes:

> As far as I tested I can say (for the 
> ffv1-supported pixelformats "gbrp10le" and 
> "gbrp12le") it works lossless. All FrameMD5s 
> are equal:

(This is not the first time that I am slightly 
surprised people use FFmpeg to prove that an 
encoder of FFmpeg is lossless.)

> The Original has LOGARITHMIC 10bit (RGB 10bit log)

FFmpeg does not support logarithmic dpx 
afaict.
If this is really a feature that would 
help you, it would be possible to force 
the "logarithmic" flag on encoding (but 
I am not convinced this is really useful).

(It is of course trivial to read the 
information from the file but I wonder 
how it would be useful given that FFmpeg 
doesn't know what to do with the 
information.)

Consider to upload a sample (or post a 
gm command line).

Carl Eugen