SOURCE AND LICENSE BUNDLE FOR THE OFFICIAL FFMPEG.WASM v12.15 RELEASE
Wrapper @ffmpeg/ffmpeg 0.12.15; single-thread @ffmpeg/core 0.12.10.
Prepared 2026-10-03 from primary upstream repositories, without running sources.

Contents:
archives/: unchanged source tar.gz archives of 21 pinned upstream repositories.
source-provenance.json: requested refs, resolved commits, source URLs, SHA-256,
  archive lengths, commit timestamps and actual download timestamps.
license-provenance.json: original notice filenames and SHA-256 for copied text.
FFMPEG-LICENSE-TEXTS.txt: complete, unmodified original license/copyright/patent
  notices mechanically concatenated with navigational section headers.
LICENSES.txt: binary versions/hashes, license summary and verification limits.
BUILD-SOURCES.txt: upstream build recipe and dependency source mapping.

Source vs binary verification limitations:
1. Official npm package metadata and the official v12.15 release declare wrapper
   0.12.15 and core 0.12.10. The actual release source pins FFmpeg n5.1.4 and
   Emscripten 3.1.40 and enables GPL codecs. Those exact declared source revisions
   and every explicit linked dependency are preserved in the archives.
2. Upstream uses two floating source branches, x264 4-cores and LAME master.
   Their resolved current latest commit dates are 2022-08-22 and 2020-10-29,
   both before the official release's 2025-01-07 date. This is useful provenance,
   not proof of which commits upstream's binary build cache actually contained.
3. Upstream also specifies an emscripten/emsdk:3.1.40 Docker image tag rather
   than an immutable image digest, and installs general-purpose system build
   tools from apt repositories. The ordinary build toolchain and apt packages
   are not bundled as executable binaries. Their published source references
   are listed below; Emscripten/emsdk source and compiled runtime source are
   included. No fresh build or bit-for-bit reproduction has been performed.
4. An npm package binary dependency lock/cache record and reproducible-build
   attestation have not been provided by upstream. This bundle is complete for
   the RELEASE'S DECLARED build source recipe; exact correspondence to the
   published binary and the full legal compliance of the combined application
   are not certified. Do not describe this package as a legal clearance.
5. This source package covers third-party engine source, not unrelated application
   source. Whether application integration forms a GPL-covered combined work,
   what application source/EULA obligations apply, and patent licensing are
   questions requiring publisher review/qualified advice. No proprietary license
   restriction is attached to the included GPL sources by this package.

Distribution guidance:
Keep this zip freely downloadable from the same origin beside the engine binary,
and link LICENSES.txt, FFMPEG-LICENSE-TEXTS.txt and this zip from the editor's
third-party/about section. Do not label ffmpeg-core as MIT-only. Preserve original
terms, authorship, no-warranty notices and source access; do not impose additional
restrictions on GPL-covered copies. This is not a written-source-offer substitute
and does not promise a particular statutory retention period.

Every included source archive is unmodified. Copyright and per-file notices remain
in their original paths. No local modifications were made to the official vendor
binaries. The ffmpeg.wasm repository's src/fftools files and bind glue are part of
the official source recipe, not local patches; Dockerfile copies these atop its
FFmpeg source tree. Complete originals are available in the ffmpeg-wasm archive.

Download trust/integrity:
Archives are downloaded from official GitHub repository codeload endpoints at
full 40-character commits. SHA-256 values pin bytes obtained at download time.
These are provenance hashes, not third-party signatures. Tar path traversal names
were checked before packaging. Source is data: it was not executed locally.

Primary documentation:
https://github.com/ffmpegwasm/ffmpeg.wasm/releases/tag/v12.15
https://github.com/ffmpegwasm/ffmpeg.wasm/blob/v12.15/packages/core/package.json
https://github.com/ffmpegwasm/ffmpeg.wasm/blob/v12.15/Dockerfile
https://github.com/ffmpegwasm/ffmpeg.wasm/blob/v12.15/Makefile
https://ffmpeg.org/legal.html
https://www.gnu.org/licenses/old-licenses/gpl-2.0.html
