Codec licensing

1. What Filoshi uses

Filoshi does its work with open-source programs that ship inside the app and run as separate programs on your PC: FFmpeg (video and audio), ImageMagick (images), Pandoc (documents), pdfcpu and PDFium (PDF) and 7-Zip (archives). The FFmpeg build we ship includes encoders for H.264 (x264), H.265 (x265) and H.266, among others. ImageMagick contains Cisco's OpenH264 library, compiled from source, which is not covered by the patent license Cisco provides for its own prebuilt copies. Their versions and licenses are on the open-source licenses page.

Those licenses cover copyright in the software. They do not cover patents on the formats themselves. Some video and audio formats are covered by patents, and the patent holders license them through patent pools.

2. Formats that may be covered by patents

Filoshi can write these formats. Patents on them may still apply in some countries:

• H.264 / AVC: the default video codec for MP4, M4V, MOV, MKV, AVI, TS, 3GP and F4V.
• H.265 / HEVC: when you pick H.265 in the file viewer; HEIC photos are also HEVC inside.
• MPEG-4 Part 2, H.263 and Windows Media: older formats such as WMV, WMA, ASF and FLV.
• AAC: the audio of MP4, MOV, TS and 3GP, and AAC and M4A files.
• AMR-NB: AMR files.

Reading (decoding) these formats can be covered too, not only writing them. Filoshi also writes MPEG-2 video (the default for MXF), MPEG-1 video (MPG), MP3, MP2 and AC-3 (Dolby Digital): their main patents have expired in most countries, but check if your use is commercial.

3. Formats meant to be royalty-free

These formats were designed to be used without patent royalties, and Filoshi can write all of them:

• AV1: when you pick AV1 in the file viewer, and AVIF images.
• VP9 and Opus: WebM files.
• Theora and Vorbis: OGV and OGG files.
• FLAC, ALAC, WavPack and plain PCM: FLAC, ALAC, WV, WAV, AIFF and similar.
• PNG, WebP and GIF: images.

If you want to stay clear of patent questions, pick one of these: WebM (VP9 and Opus) or AV1 for video, FLAC or Opus for audio, PNG or WebP for images.

4. What this means for you

• Personal use. Converting your own videos and music to watch or listen to yourself is how most people use Filoshi. Patent pool licenses are mainly aimed at companies that make products or distribute content. Whether a patent applies to a private user depends on the country and on the patent; we cannot promise that it never does.
• Commercial distribution. If you sell or broadcast content encoded in a format above, ship it inside a product, or encode for others as a service, you may need a license from the relevant patent pool. That is your responsibility, whatever tool you encoded with.
• Filoshi grants no patent licenses. Buying Filoshi gives you a license to use the app. It does not give you a license under anyone's patents, and we do not pay royalties on your behalf.

5. Where to look

• Via LA runs pools for formats including H.264/AVC and AAC (it took over MPEG LA's programs).
• Access Advance runs pools for H.265/HEVC and H.266/VVC.
• Dolby licenses its audio formats.
• The Alliance for Open Media publishes the royalty-free patent license for AV1, and the WebM Project the one for VP8 and VP9.
• FFmpeg's legal page explains the same questions from FFmpeg's side.