Uchia — Short Video Summarizer

AI-powered summarizer for TikTok, YouTube Shorts, Instagram Reels, Bilibili, and Xiaohongshu videos. Paste a link, get a structured breakdown in seconds. Also ships a real-time screen translation overlay for Android.

Live app → uchia.io Download APK → Latest release

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What it does

• Summarize any short video — TikTok, YouTube Shorts, Instagram Reels, Bilibili, Xiaohongshu
• Extract full subtitles — pull the full transcript from supported videos, with bilingual side-by-side output when the transcript language differs from the selected app language
• Gemini 2.5 Flash analysis — visuals, subtitles, humor/meme structure, overall impression
• Real-time screen translation — Android overlay that captures any app's screen, OCR-detects subtitles, and translates them live using ML Kit (fully on-device, no network needed)
• Free tier — 15 summaries included, no account required to start
• Multi-platform — Expo web app + native Android APK

Architecture

┌─────────────────────────────────────────────────┐
│                   Expo App (TypeScript)          │
│         React Native + Web (Vercel)              │
└──────────────────────┬──────────────────────────┘
                       │ REST
┌──────────────────────▼──────────────────────────┐
│              FastAPI Backend (Python)            │
│         Railway — web + celeryworker + redis     │
│                                                  │
│  yt-dlp download → Gemini 2.5 Flash analysis    │
│  Platform abstraction: TikTok / YouTube / IG / XHS│
└──────────────────────┬──────────────────────────┘
                       │
┌──────────────────────▼──────────────────────────┐
│           Supabase (Auth + DB)                   │
│    users · summaries · usage quota tracking      │
└─────────────────────────────────────────────────┘

Android Live Translation (separate, on-device):
  MediaProjection → FrameDiffSampler → ML Kit OCR
  → ML Kit Translate → PositionalOverlayView

Tech Stack

Layer	Tech
Frontend	Expo (React Native + Web), TypeScript
Backend	FastAPI, Celery, Redis
AI	Gemini 2.5 Flash (video analysis)
Video download	yt-dlp
Auth / DB	Supabase
Android translation	ML Kit OCR + Translate, MediaProjection (Kotlin)
Deployment	Vercel (frontend), Railway (backend)

Platforms supported

Platform	Status
TikTok	✅
YouTube Shorts	✅
Instagram Reels	✅
Bilibili	✅
RedNote	✅

Running locally

Backend

cd backend
pip install -r requirements.txt
cp .env.example .env   # fill in GEMINI_API_KEY, SUPABASE_URL, SUPABASE_KEY
uvicorn main:app --reload

Frontend

cd app
npm install
npx expo start

Android APK (local build)

cd app/android
./gradlew assembleDebug
# APK → app/android/app/build/outputs/apk/debug/

Environment variables

Variable	Where	Purpose
GEMINI_API_KEY	backend	Gemini API access
SUPABASE_URL	backend + app	Supabase project URL
SUPABASE_ANON_KEY	app	Supabase public key
SUPABASE_SERVICE_KEY	backend	Supabase admin key
YOUTUBE_COOKIES	Railway celeryworker	Cookie string for age-gated videos
INSTAGRAM_COOKIES	Railway celeryworker	Cookie string for Instagram downloads
BILIBILI_COOKIES	Railway celeryworker	Cookie string for Bilibili videos that require a logged-in session
XIAOHONGSHU_COOKIES	Railway celeryworker	Optional cookie string for Xiaohongshu videos that require a logged-in session
REDIS_URL	Railway	Celery broker

License

MIT