README.md

# Staticplay SD1 Mobile (On-Device, Android)

Goal: ship a real offline Android app (no servers, no cloud) that runs an SD1-class model on-device using NNAPI (via a native runtime).

This repo currently includes a working offline SD1.5 ONNX "pack" runner (unzip + inspect + generate).

Key points (no surprises)

• Use a prebuild / native build (Expo Go won't cut it for native inference).
• "Offline" means the model files are on the phone (bundled in the APK or copied into app storage).
• ONNX Runtime is integrated via a tiny Android native module (no JSI auto-install).

Run (Android)

cd /home/tiny/projects/staticplay-sd1-mobile
export ANDROID_HOME=/home/tiny/Android/sdk
export PATH="$ANDROID_HOME/platform-tools:$PATH"
npx expo prebuild --clean
npx expo run:android   # debug (uses Metro)

For a fully offline build (no Metro), install the release build:

cd /home/tiny/projects/staticplay-sd1-mobile/android
NODE_ENV=production ./gradlew :app:installRelease

Then press "Test native ONNX (NNAPI -> CPU)" in the app.

Bundle With Expo (Windows, release APK)

Use these commands from this project root.

# 1) Install dependencies (once)
npm install

# 2) Regenerate native Android project if config/plugins changed
npx expo prebuild --platform android --clean

# 3) Build release APK
cd android
./gradlew.bat :app:assembleRelease

# 4) Install to connected phone (USB debugging on)
./gradlew.bat :app:installRelease

APK output path:

android/app/build/outputs/apk/release/app-release.apk

Notes:

• This v2 build uses package id com.anonymous.staticplaysd1mobile.v2, so v1 can stay installed.
• Some setup buttons can take longer than expected (especially inspect actions).
• Generation works offline but is still being optimized for speed.
• Website: https://staticplay.co.uk

SD1.5 pack + generation (offline)

1. Put the SD1.5 ONNX pack zip at the app external directory as:

/storage/emulated/0/Android/data/com.anonymous.staticplaysd1mobile/files/sd15-onnx-pack.zip

2. In the app:

   • (Optional) Show app external pack path (for sanity check)
   • Unzip SD15 pack from external (one-time; can take minutes)
   • Load tokenizer (bundled) (no external files required)
   • Toggle backend:
     • Backend: NNAPI (experimental) = fastest, can be unstable on some devices/drivers
     • Backend: CPU (safe) = slower, but avoids NNAPI driver issues
   • Generate 512x512 (quick 4) to prove the end-to-end pipeline
   • Generate 512x512 (quality 20) for higher quality (slower)

3. Output images save to the same app external folder as sd_out_*.png.

SD1 plan (high level)

1. Pick an SD1 distilled variant (LCM/Turbo-style) to keep steps ~4-8.
2. Export components to ONNX (text encoder, UNet, VAE decoder).
3. Quantize mostly UNet (INT8) + keep VAE in FP16/BF16.
4. Run inference via a native runtime with NNAPI; fall back to CPU if NNAPI can't compile a node.
5. Ship the ONNX files in-app (or as offline downloadable packs).

V2 notes (2026-02-12)

• This branch installs as a separate app id (com.anonymous.staticplaysd1mobile.v2) so v1 stays on device.
• Guided mode is enabled to show one button at a time for easier setup flow.
• Some actions can take longer than expected, especially:
  • Inspect pack UNet
  • Inspect pack text_encoder
  • Inspect pack vae_decoder
  • first unzip/generation after launch
• Overall generation is currently functional but still slower than target. Ongoing work is focused on speed improvements.
• Public site: https://staticplay.co.uk