Fix iOS pixel format label for default byte order#159
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CGImage's .orderDefault byte order has big-endian semantics: the components are stored in memory in the order alphaInfo names them (for example premultipliedLast + orderDefault is physically [R, G, B, A]). It is a property of the Core Graphics format description, not the host CPU's endianness. getPixelFormat treated .orderDefault as little-endian, so toRawPixelData reported reversed pixel format labels for ImageIO-decoded images (such as PNG/JPEG loads). Treat .orderDefault as big-endian so the reported label matches the physical bytes.
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What
CGImage's.orderDefaultbyte order has big-endian semantics: components are stored in memory in exactly the orderalphaInfonames them (for examplepremultipliedLast + orderDefaultis physically[R, G, B, A], the classic RGBA context). This is a property of the Core Graphics format description, not the host CPU's endianness.getPixelFormattreated.orderDefaultas little-endian, sotoRawPixelDatareported reversed pixel format labels (R and B swapped) for ImageIO-decoded images such as PNG/JPEG loads. Camera-frame-style images that carry an explicitbyteOrder32Littlewere unaffected.Fix
Treat
.orderDefaultas big-endian so the reportedpixelFormatmatches the physical bytes. Also documents that thenoneSkippadding byte is intentionally reported as alpha (Apple's decoders fill it with0xFF).🤖 Generated with Claude Code