# Video repair engine for johnmcm.com

The engine behind johnmcm.com's video repair page (/repair-video): untrunc by
Federico Ponchio and contributors (GPL-2.0-or-later), with FFmpeg 3.3.9 built
from LGPL-2.1-or-later parts only, compiled to WebAssembly by FootageRescue's
engine (https://github.com/aletripodi/footagerescue-engine).

It runs as a separate program in its own Web Worker. The page talks to it only
through the worker's messages: it hands over the two files and gets back new
headers and a list of byte ranges.

The complete corresponding source of what the site serves from
/vendor/local/untrunc@1/:

- `source/engine/`: the engine repository at commit
  `179bf09cc8db7ec9a29de14ffa7a9ddf3a2924e3` (untrunc, the WebAssembly glue,
  the worker, and the build scripts), without its git history.
- `source/ffmpeg-3.3.9.tar.xz`: the FFmpeg release it compiles in
  (SHA-256 ae34f14fffa65a1a59b256737ca9af7bf4e296b7c4320d42512350126ce06c84).
- `build.ps1`: how this site builds it. Its one change is to the worker: two
  more methods ("sv" and "s-sv") that pass untrunc's own `-sv` option; the
  served worker starts with a notice saying so.

To rebuild: run `build.ps1` with Docker Desktop running.