modbender Step ASR - Streaming Speech-to-Text
Transcribe audio files using the Step (StepFun) ASR API with HTTP SSE streaming.
Quick start
python3 {baseDir}/scripts/transcribe.py /path/to/audio.wav
Usage examples
Basic transcription (Chinese, streaming output):
python3 {baseDir}/scripts/transcribe.py /path/to/audio.wav
Specify language and save to file:
python3 {baseDir}/scripts/transcribe.py /path/to/audio.mp3 --language en --out /tmp/transcript.txt
Use a prompt for terminology correction:
python3 {baseDir}/scripts/transcribe.py /path/to/audio.pcm --prompt "Related terms: OpenClaw, StepFun, ASR"
Output as JSON (includes usage stats):
python3 {baseDir}/scripts/transcribe.py /path/to/audio.ogg --json
Non-streaming mode (only print final result):
python3 {baseDir}/scripts/transcribe.py /path/to/audio.wav --no-stream
Specify audio format explicitly (for raw PCM files without extension):
python3 {baseDir}/scripts/transcribe.py /path/to/raw_audio --format-type pcm --sample-rate 16000
Supported audio formats
| Format | Extensions | Notes |
|---|---|---|
| PCM | .pcm, .raw |
Raw PCM, default codec pcm_s16le |
| WAV | .wav |
WAV container format |
| MP3 | .mp3 |
|
| OGG/OPUS | .ogg, .opus |
All options
| Flag | Default | Description |
|---|---|---|
--language |
zh |
Language code (zh or en) |
--model |
step-asr |
ASR model name |
--out |
(stdout) | Save transcription to file |
--prompt |
(none) | Hint text to improve accuracy for domain-specific terms |
--format-type |
(auto) | Audio format: pcm, mp3, ogg (auto-detected from extension) |
--sample-rate |
16000 |
Audio sample rate in Hz |
--no-stream |
false |
Only print the final complete result |
--json |
false |
Output as JSON with usage statistics |
--no-itn |
false |
Disable inverse text normalization |
--no-rerun |
false |
Disable second-pass error correction |
API key
Set STEPFUN_API_KEY environment variable, or configure it in ~/.openclaw/openclaw.json:
{
skills: {
"step-asr": {
apiKey: "YOUR_STEPFUN_API_KEY"
}
}
}
Get your API key from Step Platform.