8254ccde86
- Dockerfile + docker-compose.yml: two services (recorder + web) sharing ./recordings bind mount; recorder maps /dev/snd for ALSA soundcard access - requirements.txt: requests, numpy, soundfile - .dockerignore, updated .gitignore (add __pycache__, .pytest_cache) - isr.py: add SIGTERM handler for clean Docker shutdown; fix stale error message that referenced removed PulseAudio/PipeWire/PortAudio backends - web.py: translate all German UI strings to English - config.example.ini: remove PipeWire/PulseAudio/PortAudio backend refs, simplify soundcard tips to ALSA only - README.md: full rewrite as user guide (quick start, config reference, Docker notes, how it works) - CLAUDE.md: update architecture section to reflect ALSA-only backend - Delete changelog.txt and guide.md (internal session notes)
190 lines
6.7 KiB
Markdown
190 lines
6.7 KiB
Markdown
# ISR — Audio Recorder
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> AI-generated code. Run at your own risk. MIT licence.
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Records from multiple simultaneous sources — Icecast/HTTP streams and ALSA soundcards — with time-based file splitting.
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## Features
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- Multiple sources recorded in parallel (each in its own thread)
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- **Stream recording** — HTTP/Icecast, auto-detects MP3 / OGG / AAC / FLAC / Opus from `Content-Type`
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- **Soundcard recording** — ALSA (`arecord`), works on any Linux / Raspberry Pi
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- Time-aligned file splits (e.g. every hour, on the hour)
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- OGG / Opus / FLAC header injection so every split file is independently playable
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- Auto-reconnect on stream drops or device errors
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- WAV and FLAC output for soundcard sources
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- Web UI to browse, download, and analyse recordings
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---
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## Quick start — bare-metal
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```bash
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pip install requests # stream recording
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pip install numpy soundfile # FLAC output + web waveform analysis (optional)
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cp config.example.ini config.ini
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# edit config.ini to add your sources
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python isr.py # start recorder (Ctrl+C to stop)
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python web.py # start web UI at http://localhost:8080
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```
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## Quick start — Docker
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```bash
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cp config.example.ini config.ini
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# In config.ini set: output_directory = /recordings
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# Optionally set: log_file = /recordings/recorder.log
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docker compose up -d
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# recorder starts immediately; web UI at http://<host>:8080
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docker compose logs -f # tail logs from both services
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docker compose down # graceful stop
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```
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Recordings land in `./recordings/` on the host (bind-mounted into both containers).
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If you only record streams (no soundcard), comment out the `devices` block in `docker-compose.yml`.
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---
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## Configuration
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`config.ini` uses standard INI format. `[general]` provides defaults; every other section is a recording source. Source sections inherit all general settings and can override any of them.
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### `[general]`
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| Key | Default | Description |
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|-----|---------|-------------|
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| `output_directory` | `recordings` | Output path. Use `/recordings` in Docker. |
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| `split_minutes` | `60` | Split into a new file every N minutes, aligned to clock boundaries (e.g. 60 → files start at :00, 30 → at :00 and :30). |
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| `filename_pattern` | `%Y%m%d_%H%M%S` | strftime pattern; file extension is appended automatically. |
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| `max_retries` | `10` | Give up after this many consecutive failures per source. |
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| `retry_delay_seconds` | `5` | Wait between retries. |
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| `log_level` | `INFO` | `DEBUG` / `INFO` / `WARNING` / `ERROR` / `CRITICAL` |
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| `log_file` | `recorder.log` | Log file path. Use `/recordings/recorder.log` in Docker. |
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### `type = stream`
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```ini
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[my_stream]
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type = stream
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url = http://icecast.example.com:8000/live
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username = # leave blank for public streams
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password =
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format = auto # auto | mp3 | ogg | aac | flac | opus
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```
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`format = auto` detects from the `Content-Type` response header. For OGG/Opus/FLAC the first ~16 KB of each connection is buffered to extract codec headers, which are then prepended to every split file — all files are independently playable.
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A new file is always opened on (re)connect so gaps between connections are never silently merged.
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### `type = soundcard`
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```ini
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[mic_in]
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type = soundcard
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device = default # see device selection below
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sample_rate = 44100
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channels = 2
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format = wav # wav | flac
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```
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**Device selection:**
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| Value | Behaviour |
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|-------|-----------|
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| `default` | System default input |
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| `monitor` | First loopback/monitor source (capture system audio) |
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| `<partial name>` | Case-insensitive substring match against device name |
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| `hw:X,Y` | Exact ALSA hardware ID |
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Run `python isr.py --list-devices` (or `arecord -l`) to see available devices and their IDs.
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FLAC output requires `pip install soundfile numpy`.
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### Multiple sources
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Every section except `[general]` is a source — they all record simultaneously:
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```ini
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[general]
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output_directory = recordings
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split_minutes = 60
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[radio1]
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type = stream
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url = http://radio.example.com:8000/stream1
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filename_pattern = radio1_%Y%m%d_%H%M%S
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[system_audio]
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type = soundcard
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device = hw:0,0
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filename_pattern = system_%Y%m%d_%H%M%S
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```
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---
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## Filename patterns
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strftime codes are substituted at split time. The file extension is added automatically.
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| Pattern | Example |
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|---------|---------|
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| `%Y%m%d_%H%M%S` | `20241225_143000.mp3` |
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| `radio_%Y-%m-%d_%H%M` | `radio_2024-12-25_1430.mp3` |
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| `%Y/%m/%d/rec_%H%M%S` | `2024/12/25/rec_143000.mp3` *(subdirs created automatically)* |
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---
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## Web UI (`web.py`)
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```bash
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python web.py # serves ./recordings on port 8080
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python web.py --dir /path/to/audio # custom recordings directory
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python web.py --port 8888 # custom port
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python web.py --threshold 0.03 # loudness threshold 0–1 (default 0.05)
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```
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Shows a table of all recordings sorted newest-first with file size, duration (WAV only), and a waveform analysis button. Analysis computes RMS per 100 ms window and highlights contiguous sections above the loudness threshold.
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Waveform analysis is WAV-only; numpy speeds it up significantly (pure-Python fallback available without it).
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---
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## How it works
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**Streams:** Connect via HTTP → detect format from `Content-Type` → buffer first ~16 KB to extract OGG/FLAC codec headers → stream raw bytes to disk → at each split boundary open a new file and prepend the saved headers. No transcoding, no decoding — raw bytes in, raw bytes out.
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**Soundcard:** Spawn `arecord` as a subprocess (raw PCM output) → read 100 ms chunks via a thread → write 16-bit PCM to WAV or FLAC → split at configured boundaries.
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Both recorder types run in separate threads and retry independently up to `max_retries`.
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---
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## Docker notes
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**ALSA device access:** The `recorder` container needs `/dev/snd` mapped. The container runs as root, so no group configuration is needed — the device mapping alone is sufficient.
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If ALSA still fails to find the device inside the container, verify the device exists on the host:
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```bash
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arecord -l # list capture hardware
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ls -la /dev/snd # check device nodes
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```
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**Stream-only deployments:** If you don't use soundcard recording, remove the `devices` block from `docker-compose.yml` — the image works fine without it.
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**Log file in Docker:** Set `log_file = /recordings/recorder.log` in `config.ini` so logs survive container restarts. Alternatively, use `docker compose logs` (the recorder always logs to stdout as well).
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**File retention:** ISR never deletes recordings. Add a cron job on the host if needed:
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```bash
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# Delete recordings older than 30 days
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find recordings/ -type f -mtime +30 -delete
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```
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---
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## Licence
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MIT
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