| --- |
| license: mit |
| language: en |
| library_name: onnx |
| tags: |
| - text-to-speech |
| - tts |
| - kokoro |
| - piper |
| - kittentts |
| - vits |
| - styletts2 |
| - onnx |
| - sherpa-onnx |
| - on-device |
| - threadcast |
| pipeline_tag: text-to-speech |
| --- |
| |
| <p align="center"> |
| <a href="https://threadcast.app"> |
| <img src="assets/logo.png" alt="ThreadCast" width="160" height="160" /> |
| </a> |
| </p> |
| |
| <h1 align="center">ThreadCast — Neural Models Mirror</h1> |
|
|
| <p align="center"> |
| <em>Threads, now a podcast.</em><br/> |
| <a href="https://threadcast.app">threadcast.app</a> · <a href="https://pixellabs.ventures">pixellabs.ventures</a> |
| </p> |
|
|
| --- |
|
|
| Self-hosted mirror of the on-device neural TTS models used by **[ThreadCast](https://threadcast.app)** across both shipping platforms — the Chrome extension and the Android app. Three engine families on Android (Piper VITS, KittenTTS-nano VITS, Kokoro StyleTTS2), two on the extension, one source of truth. |
|
|
| This repository exists so each platform can ship a stable, version-pinned set of model weights without depending on the availability or rate-limits of upstream Hugging Face repos at runtime. |
|
|
| > **Note:** if you're a ThreadCast user, you don't need anything here — the extension and the Android app each download (or bundle) what they need automatically. This page is for transparency, contributors, and forks. |
|
|
| --- |
|
|
| ## Repository layout |
|
|
| ``` |
| threadcast-neural-models/ |
| ├── extension/ ← Chrome extension — HF transformers.js packaging |
| │ ├── neural-28m/ Piper VITS — 5 voices, raw HF format |
| │ └── neural-82m/ Kokoro StyleTTS2 — 1 model + 11 voice embeddings |
| │ |
| └── mobile-android/ ← Android app — production zips fetched at runtime |
| └── v1/ 8 zips: 1 shared espeak + 5 per-voice Piper |
| + 1 KittenTTS-nano ("Local AI Plus") |
| + 1 Kokoro ("Local AI Studio") |
| ``` |
|
|
| | Subtree | Format | Consumed by | Sub-README | |
| |---|---|---|---| |
| | `extension/` | Raw HF (per-file `.onnx`, `.bin`, `tokenizer.json`) | Chrome extension via `@huggingface/transformers` + `@realtimex/piper-tts-web` | [extension/README.md](extension/README.md) | |
| | `mobile-android/` | ZIP archives, sherpa-onnx packaging | Android app at runtime via [AssetInstaller.kt](https://github.com/Pixel-Labs/Reddit-Reader/blob/main/packages/mobile/modules/threadcast-neural/android/src/main/java/app/threadcast/neural/AssetInstaller.kt) — first-launch download with cancel/delete | [mobile-android/README.md](mobile-android/README.md) | |
|
|
| The two subtrees parallel each other on purpose — same engine families (Piper VITS, Kokoro StyleTTS2), same `neural-28m` / `neural-82m` parameter-count naming, just packaged for each platform's runtime. |
|
|
| --- |
|
|
| ## Engines at a glance |
|
|
| | Engine | Architecture | Params | Per-voice cost | Quality tier | |
| |---|---|---|---|---| |
| | **`neural-28m`** | Piper VITS | ~28 M | One ONNX file per voice (~63 MB) | Standard — fast, CPU-friendly, single-thread WASM real-time on a laptop. Surfaced on Android as **Local AI Lite**, on the extension as **AI Neural CPU**. | |
| | **`neural-15m`** | KittenTTS-nano VITS | ~15 M | Single fp16 model + 8 speaker embeddings (one ~26 MB file serves all) | Sweet spot — 8 voices with style-vector switching at a fraction of the storage cost. Android-only, surfaced as **Local AI Plus**. | |
| | **`neural-82m`** | Kokoro StyleTTS2 | ~82 M | Single model + 256-dim style vectors per voice (one ~325 MB file serves all) | Premium — more natural prosody, GPU-accelerated on Chrome (WebGPU); CPU-only on Android (perf-gated). Surfaced on Android as **Local AI Studio**, on the extension as **AI Neural GPU**. | |
|
|
| --- |
|
|
| ## License |
|
|
| This repository **mirrors** upstream models for distribution stability. Each upstream project retains its own license: |
|
|
| - **Kokoro-82M:** Apache-2.0 ([upstream model card](https://huggingface.co/hexgrad/Kokoro-82M)) |
| - **KittenTTS-nano (v0.1):** Apache-2.0 ([upstream model card](https://huggingface.co/KittenML/kitten-tts-nano-0.1)) |
| - **Piper voices:** MIT, with individual voice attributions in each `.onnx.json` |
| - **transformers.js, onnxruntime-web, onnxruntime-android:** Apache-2.0 |
| - **sherpa-onnx:** Apache-2.0 |
|
|
| The mirror layout, READMEs, and any custom additions in this repository are licensed under MIT by [Pixel Labs](https://pixellabs.ventures). |
|
|
| --- |
|
|
| ## Links |
|
|
| - 🌐 ThreadCast: [threadcast.app](https://threadcast.app) |
| - 🧑💻 Pixel Labs: [pixellabs.ventures](https://pixellabs.ventures) |
| - 🐦 Issues / questions: open an issue on the [ThreadCast extension repo](https://threadcast.app/support) |
|
|
