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by Kye 882 days ago
That's what DNG is for.
1 comments
lifthrasiir 882 days ago
I mean, JPEG XL is designed as an all-encompassing file format that also subsumes RAW and DNG. On the other hand, DNG 1.7.0.0 added JPEG XL as one of compression options back in 2022 (!), which might be what Samsung is actually using.
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112233 882 days ago
Where can I read more about JPEG XL subsumming of raw? As far as I understand, you cannot specify differen colorspace for different subsets of pixels?
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lifthrasiir 881 days ago
That is done by a custom ICC profile. JPEG XL's own colorspace support is more like a shorthand for frequent presets.
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112233 881 days ago
how can custom ICC profile encode information about bayer filter layout, dark frame or dead/phase photosites?
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lonjil 881 days ago
The parent commenter is incorrect. Yes, the JXL authors do want to try to use JXL as a raw format, but they are focusing on other priorities right now, so the specification for how JXL could be used as a raw format doesn't exist yet. But the format is flexible enough to allow for it, without backwards-incompatible changes.
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lifthrasiir 881 days ago
Ah, yeah, the current JPEG XL is not enough for the full RAW coverage. (I was talking more about per-channel color spaces.) There is indeed a reserved extra channel type for specific filter layouts among others, but its specification doesn't exist yet.
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