Technical details
Supported Framerates
| Framerate | Type | Drop-Frame | Common Usage |
|---|---|---|---|
| 23.976 fps | NTSC Film | Yes (;) | Film transferred to NTSC |
| 24.000 fps | Film | No (:) | Cinema, digital film |
| 25.000 fps | PAL | No (:) | European broadcast |
| 29.97 fps | NTSC | Yes (;) | North American SD broadcast |
| 30.000 fps | NTSC Progressive | No (:) | Progressive scan NTSC |
| 50.000 fps | PAL Progressive | No (:) | European HD broadcast |
| 59.94 fps | NTSC HD | Yes (;) | North American HD broadcast |
| 60.000 fps | Progressive HD | No (:) | High framerate progressive |
| 119.88 fps | HFR NTSC | Yes (;) | High framerate NTSC-derived |
| 120.00 fps | HFR Progressive | No (:) | High framerate progressive |
Note: Drop-frame timecode “drops” frame numbers (not actual frames) at the start of each minute except every 10th minute. This keeps timecode synchronised with real clock time for NTSC framerates.
Audio Format Compatibility
| Format | Channel Routing | Loudness Normalisation | Notes |
|---|---|---|---|
| PCM (WAV/AIF) | ✅ Full support | ✅ Full support | Recommended for QC work |
| AAC (Multi-channel) | ✅ Full support | ✅ Full support | Common in MP4/MOV containers |
| FLAC (Multi-channel) | ✅ Full support | ✅ Full support | Lossless compression |
| AC3/E-AC3 | ⚠️ Limited | ✅ Full support | Use default downmix for routing |
| DTS | ⚠️ Limited | ✅ Full support | Use default downmix for routing |
| Opus | ✅ Full support | ✅ Full support | Modern codec support |
Recommendation: For maximum compatibility with channel routing features, use uncompressed PCM or losslessly compressed FLAC audio.
Loudness Standards Compliance
This suite implements industry-standard loudness normalisation:
| Standard | Target | True Peak | Region | Application |
|---|---|---|---|---|
| EBU R128 | -23 LUFS | -1 dBTP | Europe, International | Broadcast television, cinema |
| ATSC A/85 | -24 LKFS | -2 dBTP | North America | Broadcast television (CALM Act) |
| AES Streaming | -16 LUFS | -1 dBTP | Global | Podcast, streaming platforms |
Implementation: Uses FFmpeg’s loudnorm filter with linear mode for transparent, broadcast-compliant normalisation. Processing adds minimal latency suitable for real-time monitoring.