Clip float-to-uint8 conversions in save_8bit to prevent overflow wrap#9
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nick-shaw wants to merge 1 commit into
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Clip float-to-uint8 conversions in save_8bit to prevent overflow wrap#9nick-shaw wants to merge 1 commit into
nick-shaw wants to merge 1 commit into
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Casts in
save_8bitwere vulnerable to uint8 wraparound if input image values strayed slightly outside the nominal [0, 1] (float) or [0, 2^bits - 1] (integer) range — TPATs shouldn't contain out of range values, but that's not a guarantee that they won't! NumPy's.astype(np.uint8)wraps modulo 256 on overflow, producing visually broken output where bright pixels become near-black.Wrapping each expression in np.clip(..., 0, 255) is cheap and defensive: no behaviour change for in-range input, clipping of out-of-range input. Discovered via a separately-fixed analogous bug in blackmagic-io.