| --- |
| license: cc-by-4.0 |
| base_model: moondream/parakeet-ultra |
| language: [en, de, fr, es, it, pt, ru, uk, hr, sl, lv, lt, et, fi, sv, da, nl, pl, cs, sk, hu, ro, bg, el, mt] |
| pipeline_tag: automatic-speech-recognition |
| tags: [coreml, parakeet, tdt, speech-recognition, apple-silicon] |
| library_name: fluidaudio |
| --- |
| |
| # parakeet-ultra-coreml |
|
|
| Core ML build of [moondream/parakeet-ultra](https://huggingface.co/moondream/parakeet-ultra), a full-precision |
| post-training of `nvidia/parakeet-tdt-0.6b-v3`. Same architecture, 25 languages, tokenizer and output conventions as |
| v3; drop-in for the v3 component contract. Encoder is int8 linear per-channel (595 MB); decoder and joint are |
| re-exported from the Ultra checkpoint; preprocessor and vocabulary are the v3 ones. |
|
|
| ## Usage (FluidAudio ≥ next release) |
|
|
| ```swift |
| let models = try await AsrModels.downloadAndLoad(version: .ultra) |
| let asr = AsrManager() |
| try await asr.initialize(models: models) |
| let result = try await asr.transcribe(audioFileURL) |
| ``` |
|
|
| ```bash |
| swift run fluidaudiocli transcribe audio.wav --model-version ultra |
| ``` |
|
|
| ## Accuracy (FluidAudio, M-series Mac, full corpora, corpus-level WER) |
|
|
| | | v3 (Core ML) | **ultra (this repo)** | |
| |---|---:|---:| |
| | LibriSpeech test-clean (2620 files) | 2.27 % | **2.13 %** | |
| | LibriSpeech test-other (2939 files) | 4.12 % | **3.81 %** | |
| | FLEURS, 24 languages × 100 samples, mean | 14.81 % | **11.67 %** | |
|
|
| Ultra wins all 24 FLEURS languages. The int8 encoder scores the same WER as an fp16 export (2.13 % / 3.79 %). Speed |
| is within a few percent of v3 run back to back on the same machine (test-clean 126.7× vs 128.6× on the ANE). |
|
|
| ## Files |
|
|
| | File | Notes | |
| |------|-------| |
| | `Encoder.mlmodelc` | 595 MB, int8 linear per-channel, iOS 17+/macOS 14+, fixed 15 s window (`mel [1,128,1501]` → `encoder [1,1024,188]`) | |
| | `Decoder.mlmodelc` | RNNT prediction net, fp16, iOS 17+ | |
| | `JointDecisionv3.mlmodelc` | single-step joint + top-K 64, fp16, iOS 17+ | |
| | `Preprocessor.mlmodelc` | v3 mel front-end | |
| | `parakeet_vocab.json`, `parakeet_v3_vocab.json` | v3 vocabulary | |
|
|
| Conversion recipe: [FluidInference/mobius](https://github.com/FluidInference/mobius) `models/stt/parakeet-ultra/coreml`. |
| License CC-BY-4.0, as the upstream checkpoint. |
|
|
