• new API: may access all (vendor-dependent) auxiliary images (e.g. hdrgainmap, semanticskinmatte, ...)
• change the way images with odd sizes are written so that macOS can read them
• when ICC profile is present, will now write two colr boxes (nclx and ICC) into AVIF files. Also reads files with two colr boxes
• alpha image is now saved as monochrome
• loading of 16bit greyscale PNGs in heif_enc
• heif_enc, option "-E" deprecated
• remove dependency on alloca()
• fix known bugs