FA-78875 / Image orientation metadata / Member archive

Pixel bake discards valid tag 8 as invalid · case 05

Photos rotated 90 degrees counter-clockwise are baked unrotated.

Member previewVariant 5 · 3 implementations · 8 checks per implementation

Case contract

Bake an EXIF-style orientation tag (1..8) into a row-major pixel grid so the result displays upright. Tags 2/4 mirror horizontally/vertically, 3 rotates 180, 6 rotates 90 clockwise, 8 rotates 90 counter-clockwise, 5 transposes and 7 transverses; tags outside 1..8 are treated as 1. Tags 5..8 swap the output width and height.

Why this case matters

Camera, phone and scanner images carry an orientation hint separately from the stored pixels; galleries, thumbnailers, editors and upload pipelines must interpret it consistently or photos appear sideways, mirrored or doubly rotated.

One recorded failure

Sample boundary fixture

This sample comes from the broken implementation of a controlled reproducer.

Boundary fixture	Actual	Expected	Outcome
regression: invalid tag normalisation 0	`[[5, 6, 7], [15, 16, 17]]`	`[[7, 17], [6, 16], [5, 15]]`	Failed

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This record includes three runnable implementations, regression fixtures, execution results, and source hashes.

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