Darius Kazemi on Nostr: TIL that JPEG encoding in the wild is even more complicated than the very complicated ...
TIL that JPEG encoding in the wild is even more complicated than the very complicated documentation makes it out to be. For example, most references I can find say that the difference between an RGB and a CMYK jpeg is the former will have 3 "components" and the latter 4. This in theory should be encoded in a particular start-of-frame byte. And yet I have seen images detected as CMYK by ffmpeg have "03" in that byte position. And there are reports of CMYK jpegs that are really RGB under the hood?
Published at
2023-12-20 18:01:32Event JSON
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"content": "TIL that JPEG encoding in the wild is even more complicated than the very complicated documentation makes it out to be. For example, most references I can find say that the difference between an RGB and a CMYK jpeg is the former will have 3 \"components\" and the latter 4. This in theory should be encoded in a particular start-of-frame byte. And yet I have seen images detected as CMYK by ffmpeg have \"03\" in that byte position. And there are reports of CMYK jpegs that are really RGB under the hood?",
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