https://imgconvert.cloud/
ImgConvert - Image Converter for PNG, JPG, WEBP, AVIF, PDF
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https://ffmpeg.org/doxygen/2.7/imgconvert_8c_source.html
FFmpeg: libavcodec/imgconvert.c Source File
ffmpeglibavcodecimgconvertsourcefile
https://ffmpeg.org/doxygen/4.1/tests_2imgconvert_8c_source.html
FFmpeg: libavcodec/tests/imgconvert.c Source File
ffmpeglibavcodectestsimgconvertsource