Alt C Media App
Codecs and Formats
What altc plays as-is on each device, and what needs the server to transcode.
Apple covers iPhone, iPad and Vision Pro. Android covers phones, tablets and Android XR. Meta Quest is listed on its own because its decoder and display set differ from other Android devices. Steam Frame runs the SteamOS app.
Video Support
Codecs, HDR and Dolby Vision, resolution, 3D and subtitles.
Audio Support
Codecs, passthrough, channels and music.
3D and Spatial VR Formats
3D, 180°, 360° and fisheye video, and how to name your files.
Containers
| Container | Apple | Android | Meta Quest | Steam Frame | Notes |
|---|---|---|---|---|---|
| MP4 · MOV · M4V | ✓ | ✓ | ✓ | ✓ | |
| MKV · MKA | ✓ | ✓ | ✓ | ✓ | |
| WebM | ✓ | ✓ | ✓ | ✓ | VP8, VP9, AV1, Opus and Vorbis inside it all play. |
| VP8, VP9, AV1, Opus and Vorbis inside it all play. | |||||
| MPEG-TS · M2TS | ✓ | ✓ | ✓ | ✓ | |
| HLS (m3u8) | ✓ | ✓ | ✓ | ✓ | |
| MP3 · AAC · FLAC · Ogg (audio files) | ✓ | ✓ | ✓ | ✓ | Ogg: Opus, Vorbis and FLAC. |
| Ogg: Opus, Vorbis and FLAC. | |||||
| AVI · WMV · FLV · VOB | ✕ | ✕ | ✕ | ✕ | |
Direct play or transcode
Whether a file plays as-is or is transcoded by the server is decided by bitrate, never by codec:
- Quality set to Original: always direct play.
- Quality set to Auto: direct play when the file's bitrate fits your measured connection speed; otherwise the server transcodes.
- High, Medium or a custom tier: direct play when the file's bitrate fits the tier; otherwise the server transcodes.