A proprietary variable codec audio file format designed for dictation by NCH Software. It has dictation header information and can be encrypted (often required by medical confidentiality laws). A free dct player, Express Scribe Transcription is provided.
| Format | Bitrate | 1 Min = | Sample |
|---|---|---|---|
| 11,025Hz 16bit PCM | 176.4kbs | 1292k | 11k16bitpcm.wav |
| 8000Hz 16bit PCM | 128kbs | 937.5k | 8k16bitpcm.wav |
| 11,025Hz 8bit PCM | 88.2kbs | 646k | 11k8bitpcm.wav |
| 11,025Hz u-Law | 88.2kbs | 646k | 11kulaw.wav |
| 8,000Hz 8bit PCM | 64kbs | 468.8k | 8k8bitpcm.wav |
| 8,000Hz u-Law | 64kbs | 468.8k | 8kulaw.wav |
| 11,025Hz 4bit ADPCM | 44.1kbs | 323k | 11kadpcm.wav |
| 8000Hz 4bit ADPCM | 32kbs | 234.4k | 8kadpcm.wav |
| 11,025Hz GSM6.10 | 18kbs | 131.8k | 11kgsm.wav |
| 8000Hz Mp3 16k | 16kbs | 117k | 8kmp316.wav |
| 8,000Hz GSM6.10 | 13kbs | 102.5k | 8kgsm.wav |
| 8000Hz Lernout & Hauspie SBC 12k | 12.0kbs | 87.9k | 8ksbc12.wav |
| 8,000Hz DSP Group Truespeech | 9kbs | 65.9k | 8ktruespeech.wav |
| 8000Hz Mp3 8k | 8kbs | 60k | 8kmp38.wav |
| 8,000Hz Lernout & Hauspie CELP | 4.8kbs | 35k | 8kcelp.wav |
The above are wave files - even if they have the mp3 codec they will have the ".wav" or ".dct" extension.