FA-79162 / Image orientation metadata / Member archive

Segment length limit ignores the length field itself · case 02

A 65534-byte APP1 payload is accepted although its length field would overflow.

Member previewVariant 2 · 3 implementations · 8 checks per implementation

Case contract

Input: JPEG segments as [marker, payload] with the payload as a latin-1 string. The stream must start with SOI (0xD8) or the result is "not-jpeg". Scan segments after SOI until SOS (0xDA) or EOI (0xD9); a payload longer than 65533 bytes cannot be encoded in the 16-bit length and yields "corrupt". Return the index of the first APP1 (0xE1) segment whose payload starts with "Exif\0\0", or None.

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: maximum payload length 0	`null`	`"corrupt"`	Failed

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