using code example from https://git.ffmpeg.org/gitweb/ffmpeg.git/blobdiff/f7bab37c8e66f3c77a5fbb5b5b... and test files from https://littlecms.com/img/blog/check_lut.jpg https://littlecms.com/img/blog/check_full.jpg I think I was able to make png ffmpeg encoder to add built-in profile, based on (randomly-choose) colorimetry. patch itself needed to be applied with usual patch from directory just above main cinelerra-5.1 level, and not "git am" tar.gz not included due to 7Mb size! Fake colorimetry I used: ======== # this codec creates a set of image files in a directory # use an image2 file name like /dir/p%05d.png flags2=0x80000000 colorspace=smpte2085 color_primaries=bt2020 color_trc=bt2020_12bit color_range=jpeg ==== resulted in this exiftool output: exiftool /dev/shm/4.png ExifTool Version Number : 11.11 File Name : 4.png Directory : /dev/shm File Size : 29 kB File Modification Date/Time : 2023:11:12 19:28:40+03:00 File Access Date/Time : 2023:11:12 19:28:40+03:00 File Inode Change Date/Time : 2023:11:12 19:28:40+03:00 File Permissions : rw-r--r-- File Type : PNG File Type Extension : png MIME Type : image/png Image Width : 400 Image Height : 300 Bit Depth : 8 Color Type : RGB Compression : Deflate/Inflate Filter : Adaptive Interlace : Noninterlaced Pixels Per Unit X : 1 Pixels Per Unit Y : 1 Pixel Units : Unknown Profile Name : icc Profile CMM Type : Little CMS Profile Version : 4.3.0 Profile Class : Display Device Profile Color Space Data : RGB Profile Connection Space : XYZ Profile Date Time : 2023:11:12 16:28:40 Profile File Signature : acsp Primary Platform : Apple Computer Inc. CMM Flags : Not Embedded, Independent Device Manufacturer : Device Model : Device Attributes : Reflective, Glossy, Positive, Color Rendering Intent : Perceptual Connection Space Illuminant : 0.9642 1 0.82491 Profile Creator : Little CMS Profile ID : 0 Profile Description : RGB built-in Profile Copyright : No copyright, use freely Media White Point : 0.9642 1 0.82491 Chromatic Adaptation : 1.04788 0.02292 -0.05022 0.02959 0.99048 -0.01707 -0.00925 0.01508 0.75168 Red Matrix Column : 0.67348 0.27904 -0.00194 Blue Matrix Column : 0.12505 0.04561 0.79684 Green Matrix Column : 0.16566 0.67534 0.02998 Red Tone Reproduction Curve : (Binary data 32 bytes, use -b option to extract) Green Tone Reproduction Curve : (Binary data 32 bytes, use -b option to extract) Blue Tone Reproduction Curve : (Binary data 32 bytes, use -b option to extract) Chromaticity Channels : 3 Chromaticity Colorant : Unknown (0) Chromaticity Channel 1 : 0.70799 0.29201 Chromaticity Channel 2 : 0.17 0.797 Chromaticity Channel 3 : 0.131 0.04601 Image Size : 400x300 Megapixels : 0.120 Note, of course this is WRONG kind of wrong, randomly setting colorimetry tags on encode, but at least it hopefully show that ffmpeg's machinery (6.1) works at least that far. sadly, no of those two test images show correct text, so I guess display icc profile support quite missing step for us ...! but one micro/nanostep at a time?
