HALOWERK audiowerk

Endpoints (10 live)

• POST /voice-evidence — Returns measured evidence about a recording, not a verdict on it. The spectral cut-off says which lossy stages the file has already been through, since every encoder discards everything above its own ceiling. The room tone measurement compares the noise floor across the silent stretches: a microphone in a room produces a floor that differs between pauses, and a level identical to the hundredth of a decibel across every pause means the silence was inserted rather than recorded. (0.006 USDC on Base)
• POST /dialect-classify — Classifies only three broad German-language varieties: de-DE Germany German, de-AT Austrian German and de-CH Swiss German. The model works on acoustic speech embeddings and does not read a transcript. It returns probabilities for all three classes, the strongest candidate, audio quality warnings and unknown whenever confidence or recording quality is insufficient. The result is a statistical variety estimate, not a statement about a speaker's origin, identity, nationality or place of residence. (0.006 USDC on Base)
• POST /speech-rate — Transcribes the recording, then measures rate rather than words. Two figures come back and they are not interchangeable: the gross rate over the whole running time, which is what a listener experiences, and the articulation rate over speaking time only, which is what a speaker can actually change. On a recording with normal pauses the two differ by thirty per cent or more, and coaching against the wrong one produces the wrong correction. (0.008 USDC on Base)
• POST /voice-spectrum — Computes the power spectrum from raw samples at 128 logarithmically spaced probe frequencies and sums it into six bands whose boundaries are fixed and stated in every answer: rumble below 80 Hz, the fundamental range to 250 Hz, body to 800 Hz, the second formant range to 2 kHz, the consonant range to 6 kHz, and air above that. Naming the boundaries is not decoration — a bass share quoted without them cannot be compared with anyone else's, and most tools do not say where theirs run. (0.006 USDC on Base)
• POST /speech-duration — Counts syllables rather than words, because word length differs between languages far more than syllable duration does — a German compound and its four-word English equivalent take about the same time to say and would give wildly different word counts. (0.002 USDC on Base)
• POST /duck — Takes a voice recording and a music bed and returns one mixed file in which the music is pulled down by the voice through an ffmpeg sidechain compressor. Threshold, ratio, attack and release are all settable and all reported back with the result, because they are the difference between a mix that breathes and one that pumps: a release under 100 ms makes the bed audibly flutter between words, above 1500 ms it never returns between sentences. (0.01 USDC on Base)
• POST /ad-slot-auction — Four actions on one endpoint. create opens a slot with its position, length, reserve price and closing time, and returns an admin token that only the opener holds. bid places a sealed bid, checked against the reserve, the slot length and the publisher's excluded categories before it is accepted — a rejected bid is recorded with its reason rather than silently dropped, so a bidder can see why it never competed. (0.004 USDC on Base)
• POST /trim-silence — Finds silent stretches with ffmpeg level detection and shortens each one that exceeds the threshold length. Pauses are shortened to a floor, never removed outright: a pause cut to zero makes the end of one sentence collide with the start of the next, which is a worse defect than the dead air it replaced. The floor defaults to 400 milliseconds, roughly the pause a speaker leaves between sentences, and is settable. (0.008 USDC on Base)
• POST /convert — Converts to FLAC, WAV at 16 or 24 bit, MP3, Opus or AAC, with sample rate, channel count and quality all settable and all reported back. What separates this from a bare transcode is the verdict on what the conversion actually did. The spectral cut-off of the source is measured first, so a source that already passed through a lossy stage is recognised before it is wrapped in a lossless container: converting an MP3 to FLAC multiplies the file size by roughly ten and restores nothing, and the… (0.006 USDC on Base)
• POST /loudness-normalise — Normalises to −14 LUFS by default, the level the streaming platforms converged on, with named presets for podcast, European and United States broadcast, or a free target. The correction runs in two passes: the first measures integrated loudness, true peak, loudness range and threshold, the second applies a constant correction derived from those figures. (0.008 USDC on Base)