Hi everyone,
I'm developing an iOS camera app that aims to record 4224×3024 Open Gate video at 60fps in 10-bit HEVC with Apple Log 2.
Native Apple ISP-processed Apple Log 2 capture works at 3840×2160/60fps. However, at 4224×3024/60fps, the tested capture configuration only provides Bayer RAW (btp2).
I've successfully decoded ProRes RAW using Apple's decoder into linear Rec.2020 and applied the published Apple Gamut and Apple Log 2 transforms. However, the resulting chroma is only approximately 72–74% of the native ISP output in controlled color-chart comparisons.
I've also confirmed that VTRAWProcessingSession and related RAW processing controls are not publicly available to iOS apps in the iPhoneOS 27.0 SDK.
My questions are:
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Is there a public iOS API that applies the same color and tone rendering as Apple's native camera ISP to captured Bayer RAW or ProRes RAW?
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Is there a supported configuration for obtaining full-resolution 4224×3024/60fps ISP-processed Apple Log 2 output (x420 or x422), without preview proxies or upscaling?
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If neither is supported, what is Apple's recommended approach? Is this a hardware limitation or a public API limitation?
The goal is to use Apple's official color processing pipeline without empirically fitted matrices, LUTs, or arbitrary color corrections.
Any guidance would be greatly appreciated. Thank you!