# Store runtime notices and source

The Store runtime uses FFmpeg 7.1.1 libraries under the GNU Lesser General Public License version 2.1 or later. FFmpeg is copyright its contributors. Videogen Studio does not claim ownership of FFmpeg. The complete, unmodified upstream source archive, licence, configuration and build instructions are supplied inside the app under `Contents/Resources/studio-runtime/runtime/licenses/ffmpeg`. FFmpeg's website is https://ffmpeg.org/.

This Store build disables GPL, nonfree and version-3 components, external-library autodetection and network protocols. Video encoding uses macOS VideoToolbox. Narration uses installed macOS English/Hindi voices through AVFoundation. No Kokoro, phonemizer, eSpeak, x264, x265, Xvid, Rubber Band or GPL command-line XZ tools are included in this Store runtime.

Python, Node.js and their selected native dependencies retain their individual notices under `runtime/licenses`. The included XZ component is liblzma, covered by 0BSD; XZ's other licences describe source parts that are not shipped as executable tools here. macOS system frameworks and voices are provided by Apple, separately from this package.

## Rebuild and replace FFmpeg

Copy the source archive to a writable local directory and unpack it. Build with the macOS SDK and Clang, matching the bundled architecture and minimum OS. `BUILD.txt` records the exact configuration used. No source patch is applied. The CLI tools dynamically load the adjacent libav libraries using loader-relative paths; no FFmpeg library is statically linked into the native editor or its Swift pipeline. The pipeline starts the bundled FFmpeg/FFprobe programs as separate processes.

Recipients may modify these LGPL components and reverse engineer the application for debugging those modifications as allowed by the LGPL. No application term restricts those rights. For a private modified installation, work on a copy of the app in a writable directory, replace the FFmpeg programs and compatible shared libraries in `runtime/bin` and `runtime/lib`, retain the loader-relative references, and sign the changed code and enclosing app with your own signing identity or a local ad-hoc signature. Rebuild the matching command-line programs together if changing the library ABI. A modified app is your local copy and does not retain the publisher's App Store signature or receipt verification. Keep an unchanged copy of your projects and the original app. The accompanying bundle tool records the load-command relocation and signing procedure.

## Application licence exception

Any application licence applies only to publisher-owned components. Third-party components remain under their supplied licences, which take precedence for those components. In particular, recipients retain the LGPL copying, modification, redistribution and debugging rights described above. No reverse-engineering restriction applies where it would prevent exercising those rights. The app's source-delivery materials include no private signing keys or publisher credentials.