# HEIC/HEIF fixture attribution

`sample.heic` and `sample.heif` are byte-identical copies of
`tests/data/with-alpha-512x512.heic` from the
[strukturag/libheif](https://github.com/strukturag/libheif) repository
(the reference HEIF/AVIF codec library), licensed under the project's
LGPL-3.0/MIT terms (see that repo's `COPYING` file).

Both filenames use the same content deliberately: `file-type` (the
content-sniffing library this project uses) detects any file in the
HEIC/HEIF family as `ext: 'heic'` regardless of the actual container
brand, so the `.heic` vs `.heif` distinction in this project's code is
purely about the declared source format taken from the upload's file
extension, not about decoding a differently-branded container. Reusing
one verified, cleanly-licensed sample under both extensions exercises
that code path without requiring a second real-world sample.