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Gadfly on #103: - (4 models) applyOrientation allocated a WxH RGBA then threw it away for a quarter-turn to allocate HxW. Compute the output dims once, allocate one buffer. - (perf) The At/Set loop boxed a color.Color per pixel — millions of heap allocs on a full-res rotation. Convert to *image.RGBA once (draw.Draw) then copy 4 bytes per pixel by offset. No boxing. - (2 findings) exifOrientation didn't skip 0xFF fill bytes before a marker, so a spec-valid padded APP1 would be misread. Skip them. - (2 findings) orientationFromApp1 read the tag's inline value without checking its type/count — a mistyped LONG/offset would be read as a bogus SHORT. Require type=SHORT, count=1; also validate the TIFF 0x2A magic agrees with the byte order. - Tests now cover all 8 orientations (added the mirror/transpose cases 2/4/5/7, the most error-prone switch arms) as t.Run subtests. All imagenorm tests green; gofmt clean; still CGO_ENABLED=0. Co-Authored-By: Claude Opus 4.8 (1M context) <[email protected]> Claude-Session: https://claude.ai/code/session_01H3zbym8Doka2d7D48maSgZ