Logan CusanoandClaude Opus 5
0c08275482
The single encode at save time was %mp3(bitrate=16), and the comment said why: it matched what Liquidsoap pushes to Icecast. That was the wrong thing to match. Icecast is the LISTENING path and 16 kbps is a bandwidth budget for a live stream; this file is the ACCURACY path -- it is what Whisper transcribes, and CLAUDE.md is explicit that everything downstream is hostage to it. P25 has already been through a vocoder, so 16 kbps MP3 stacked a second lossy stage on the one copy that had to stay faithful. FLAC instead. Lossless, so the bytes Whisper receives are the bytes PulseAudio captured. ~1.3 MB/min against 120 KB/min, which keeps a 600 s call (the time cap) around 13 MB -- inside Whisper's 25 MB request cap and well inside upload_max_bytes. Icecast's own 16 kbps stream is untouched; nothing about live listening changes. Capture, buffering, silence detection and the byte-offset trim are all unchanged: they operate on raw PCM and never saw the encode. The sample rate stays pinned to pcm.SAMPLE_RATE so the encode remains a straight pass -- the trim arithmetic depends on that, and Whisper resamples to 16 kHz itself. encode_mp3 is now encode_recording, the upload sends audio/flac, and the test that pinned the old contract now pins losslessness instead, including an assertion that no bitrate constant comes back. This is the before/after boundary for STT quality. Last night's window is the 16 kbps baseline. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>