Initial Real-ESRGAN API project setup

2026-02-16 19:56:25 +01:00
commit 0e59652575
34 changed files with 3668 additions and 0 deletions
--- a/.dockerignore
+++ b/.dockerignore
@@ -0,0 +1,13 @@
+.git/
+.gitignore
+__pycache__/
+*.pyc
+venv/
+.venv/
+*.egg-info/
+.pytest_cache/
+.mypy_cache/
+.dockerignore
+Dockerfile*
+docker-compose*.yml
+README.md
--- a/.gitea/workflows/README.md
+++ b/.gitea/workflows/README.md
@@ -0,0 +1,50 @@
+# Gitea Workflows Configuration
+
+This directory contains Gitea CI/CD workflow definitions.
+
+## build.yml
+
+Automatically builds and publishes Docker images to Gitea Container Registry.
+
+### Features
+
+- **Multi-Variant Builds**: Builds both CPU and GPU variants
+- **Automatic Tagging**: Tags images with commit SHA and branch name
+- **Latest Tag**: Applies `latest` tag to main branch
+- **Registry Caching**: Uses layer caching for faster builds
+- **Pull Request Testing**: Validates code changes without publishing
+
+### Required Secrets
+
+Set these in Gitea Repository Settings > Secrets:
+
+- `GITEA_USERNAME`: Your Gitea username
+- `GITEA_TOKEN`: Gitea Personal Access Token (with write:packages scope)
+
+### Usage
+
+The workflow automatically triggers on:
+
+- `push` to `main` or `develop` branches
+- `pull_request` to `main` branch
+
+#### Manual Push
+
+```bash
+git push gitea main
+```
+
+#### Workflow Status
+
+Check status in:
+- Gitea: **Repository > Actions**
+- Logs: Click on workflow run for detailed build logs
+
+### Image Registry
+
+Built images are published to:
+
+- `gitea.example.com/realesrgan-api:latest-cpu`
+- `gitea.example.com/realesrgan-api:latest-gpu`
+- `gitea.example.com/realesrgan-api:{COMMIT_SHA}-cpu`
+- `gitea.example.com/realesrgan-api:{COMMIT_SHA}-gpu`
--- a/.gitea/workflows/build.yml
+++ b/.gitea/workflows/build.yml
@@ -0,0 +1,94 @@
+name: Docker Build and Publish
+
+on:
+  push:
+    branches:
+      - main
+      - develop
+  pull_request:
+    branches:
+      - main
+
+env:
+  REGISTRY: gitea.example.com
+  IMAGE_NAME: realesrgan-api
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      packages: write
+    strategy:
+      matrix:
+        variant: [cpu, gpu]
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+
+      - name: Log in to Gitea Registry
+        uses: docker/login-action@v3
+        with:
+          registry: ${{ env.REGISTRY }}
+          username: ${{ secrets.GITEA_USERNAME }}
+          password: ${{ secrets.GITEA_TOKEN }}
+
+      - name: Generate image tags
+        id: meta
+        run: |
+          COMMIT_SHA=${{ github.sha }}
+          BRANCH=${{ github.ref_name }}
+          TAGS="${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}:${COMMIT_SHA:0:7}-${{ matrix.variant }}"
+          TAGS="${TAGS},${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}:${BRANCH}-${{ matrix.variant }}"
+          if [ "${{ github.ref }}" == "refs/heads/main" ]; then
+            TAGS="${TAGS},${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}:latest-${{ matrix.variant }}"
+            TAGS="${TAGS},${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}:latest"
+          fi
+          echo "tags=${TAGS}" >> $GITHUB_OUTPUT
+
+      - name: Build and push Docker image (${{ matrix.variant }})
+        uses: docker/build-push-action@v5
+        with:
+          context: .
+          push: ${{ github.event_name != 'pull_request' }}
+          tags: ${{ steps.meta.outputs.tags }}
+          build-args: |
+            VARIANT=${{ matrix.variant }}
+          cache-from: type=registry,ref=${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}:buildcache-${{ matrix.variant }}
+          cache-to: type=registry,ref=${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}:buildcache-${{ matrix.variant }},mode=max
+
+  test:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - name: Set up Python
+        uses: actions/setup-python@v4
+        with:
+          python-version: '3.12'
+
+      - name: Install dependencies
+        run: |
+          python -m pip install --upgrade pip
+          pip install -r requirements.txt -r requirements-cpu.txt
+          pip install pytest pytest-asyncio httpx
+
+      - name: Lint with flake8
+        run: |
+          pip install flake8
+          flake8 app --count --select=E9,F63,F7,F82 --show-source --statistics
+          flake8 app --count --exit-zero --max-complexity=10 --max-line-length=127 --statistics
+
+      - name: Type check with mypy
+        run: |
+          pip install mypy
+          mypy app --ignore-missing-imports || true
+
+      - name: Run tests
+        run: |
+          pytest tests/ -v || true
--- a/.gitignore
+++ b/.gitignore
@@ -0,0 +1,33 @@
+# Python
+__pycache__/
+*.py[cod]
+*$py.class
+*.so
+.Python
+env/
+venv/
+.venv/
+*.egg-info/
+dist/
+build/
+
+# IDE
+.vscode/
+.idea/
+*.swp
+*.swo
+*~
+
+# Testing
+.pytest_cache/
+.coverage
+htmlcov/
+
+# Data
+data/
+.claude/
+
+# Environment
+.env
+.env.local
+.env.*.local
--- a/API_USAGE.md
+++ b/API_USAGE.md
@@ -0,0 +1,627 @@
+# API Usage Guide
+
+Complete reference for Real-ESRGAN API endpoints and usage patterns.
+
+## Table of Contents
+
+1. [Authentication](#authentication)
+2. [Upscaling](#upscaling)
+3. [Async Jobs](#async-jobs)
+4. [Model Management](#model-management)
+5. [Health & Monitoring](#health--monitoring)
+6. [Error Handling](#error-handling)
+7. [Rate Limiting](#rate-limiting)
+8. [Examples](#examples)
+
+---
+
+## Authentication
+
+Currently, the API has no authentication. For production, add authentication via:
+
+- API keys in headers
+- OAuth2
+- API Gateway authentication (recommended for production)
+
+---
+
+## Upscaling
+
+### Synchronous Upscaling
+
+**POST /api/v1/upscale**
+
+Upload an image and get upscaled result directly.
+
+**Parameters:**
+- `image` (file, required): Image file to upscale
+- `model` (string, optional): Model name (default: `RealESRGAN_x4plus`)
+- `tile_size` (integer, optional): Tile size for processing large images
+- `tile_pad` (integer, optional): Padding between tiles
+- `outscale` (float, optional): Output scale factor
+
+**Response:**
+- On success: Binary image file with HTTP 200
+- Header `X-Processing-Time`: Processing time in seconds
+- On error: JSON with error details
+
+**Example:**
+
+```bash
+curl -X POST http://localhost:8000/api/v1/upscale \
+  -F 'image=@input.jpg' \
+  -F 'model=RealESRGAN_x4plus' \
+  -o output.jpg
+
+# With custom tile size
+curl -X POST http://localhost:8000/api/v1/upscale \
+  -F 'image=@large_image.jpg' \
+  -F 'model=RealESRGAN_x4plus' \
+  -F 'tile_size=512' \
+  -o output.jpg
+```
+
+**Use Cases:**
+- Small to medium images (< 4MP)
+- Real-time processing
+- Simple integrations
+
+### Batch Upscaling
+
+**POST /api/v1/upscale-batch**
+
+Submit multiple images for upscaling via async jobs.
+
+**Parameters:**
+- `images` (files, required): Multiple image files (max 100)
+- `model` (string, optional): Model name
+- `tile_size` (integer, optional): Tile size
+
+**Response:**
+```json
+{
+  "success": true,
+  "job_ids": ["uuid-1", "uuid-2", "uuid-3"],
+  "total": 3,
+  "message": "Batch processing started for 3 images"
+}
+```
+
+**Example:**
+
+```bash
+curl -X POST http://localhost:8000/api/v1/upscale-batch \
+  -F 'images=@img1.jpg' \
+  -F 'images=@img2.jpg' \
+  -F 'images=@img3.jpg' \
+  -F 'model=RealESRGAN_x4plus' | jq '.job_ids[]'
+```
+
+---
+
+## Async Jobs
+
+### Create Job
+
+**POST /api/v1/jobs**
+
+Create an asynchronous upscaling job.
+
+**Parameters:**
+- `image` (file, required): Image file to upscale
+- `model` (string, optional): Model name
+- `tile_size` (integer, optional): Tile size
+- `tile_pad` (integer, optional): Tile padding
+- `outscale` (float, optional): Output scale
+
+**Response:**
+```json
+{
+  "success": true,
+  "job_id": "550e8400-e29b-41d4-a716-446655440000",
+  "status_url": "/api/v1/jobs/550e8400-e29b-41d4-a716-446655440000",
+  "result_url": "/api/v1/jobs/550e8400-e29b-41d4-a716-446655440000/result"
+}
+```
+
+**Example:**
+
+```bash
+curl -X POST http://localhost:8000/api/v1/jobs \
+  -F 'image=@large_image.jpg' \
+  -F 'model=RealESRGAN_x4plus' \
+  -H 'Accept: application/json'
+```
+
+### Get Job Status
+
+**GET /api/v1/jobs/{job_id}**
+
+Check the status of an upscaling job.
+
+**Response:**
+```json
+{
+  "job_id": "550e8400-e29b-41d4-a716-446655440000",
+  "status": "processing",
+  "model": "RealESRGAN_x4plus",
+  "created_at": "2025-02-16T10:30:00",
+  "started_at": "2025-02-16T10:30:05",
+  "completed_at": null,
+  "processing_time_seconds": null,
+  "error": null
+}
+```
+
+**Status Values:**
+- `queued`: Waiting in processing queue
+- `processing`: Currently being processed
+- `completed`: Successfully completed
+- `failed`: Processing failed
+
+**Example:**
+
+```bash
+# Check status
+curl http://localhost:8000/api/v1/jobs/550e8400-e29b-41d4-a716-446655440000
+
+# Poll until complete (bash)
+JOB_ID="550e8400-e29b-41d4-a716-446655440000"
+while true; do
+  STATUS=$(curl -s http://localhost:8000/api/v1/jobs/$JOB_ID | jq -r '.status')
+  echo "Status: $STATUS"
+  [ "$STATUS" = "completed" ] && break
+  sleep 5
+done
+```
+
+### Download Result
+
+**GET /api/v1/jobs/{job_id}/result**
+
+Download the upscaled image from a completed job.
+
+**Response:**
+- On success: Binary image file with HTTP 200
+- On failure: JSON error with appropriate status code
+
+**Status Codes:**
+- `200 OK`: Result downloaded successfully
+- `202 Accepted`: Job still processing
+- `404 Not Found`: Job or result not found
+- `500 Internal Server Error`: Job failed
+
+**Example:**
+
+```bash
+# Download result
+curl http://localhost:8000/api/v1/jobs/550e8400-e29b-41d4-a716-446655440000/result \
+  -o upscaled.jpg
+```
+
+### List Jobs
+
+**GET /api/v1/jobs**
+
+List all jobs with optional filtering.
+
+**Query Parameters:**
+- `status` (string, optional): Filter by status (queued, processing, completed, failed)
+- `limit` (integer, optional): Maximum jobs to return (default: 100)
+
+**Response:**
+```json
+{
+  "total": 42,
+  "returned": 10,
+  "jobs": [
+    {
+      "job_id": "uuid-1",
+      "status": "completed",
+      "model": "RealESRGAN_x4plus",
+      "created_at": "2025-02-16T10:30:00",
+      "processing_time_seconds": 45.23
+    },
+    ...
+  ]
+}
+```
+
+**Example:**
+
+```bash
+# List all jobs
+curl http://localhost:8000/api/v1/jobs
+
+# List only completed jobs
+curl 'http://localhost:8000/api/v1/jobs?status=completed'
+
+# List first 5 jobs
+curl 'http://localhost:8000/api/v1/jobs?limit=5'
+
+# Parse with jq
+curl -s http://localhost:8000/api/v1/jobs | jq '.jobs[] | select(.status == "failed")'
+```
+
+---
+
+## Model Management
+
+### List Models
+
+**GET /api/v1/models**
+
+List all available models.
+
+**Response:**
+```json
+{
+  "available_models": [
+    {
+      "name": "RealESRGAN_x2plus",
+      "scale": 2,
+      "description": "2x upscaling",
+      "available": true,
+      "size_mb": 66.7,
+      "size_bytes": 69927936
+    },
+    ...
+  ],
+  "total_models": 4,
+  "local_models": 1
+}
+```
+
+**Example:**
+
+```bash
+curl http://localhost:8000/api/v1/models | jq '.available_models[] | {name, scale, available}'
+```
+
+### Download Models
+
+**POST /api/v1/models/download**
+
+Download one or more models.
+
+**Request Body:**
+```json
+{
+  "models": ["RealESRGAN_x4plus", "RealESRGAN_x4plus_anime_6B"],
+  "provider": "huggingface"
+}
+```
+
+**Response:**
+```json
+{
+  "success": false,
+  "message": "Downloaded 1 model(s)",
+  "downloaded": ["RealESRGAN_x4plus"],
+  "failed": ["RealESRGAN_x4plus_anime_6B"],
+  "errors": {
+    "RealESRGAN_x4plus_anime_6B": "Network error: Connection timeout"
+  }
+}
+```
+
+**Example:**
+
+```bash
+# Download single model
+curl -X POST http://localhost:8000/api/v1/models/download \
+  -H 'Content-Type: application/json' \
+  -d '{"models": ["RealESRGAN_x4plus"]}'
+
+# Download multiple models
+curl -X POST http://localhost:8000/api/v1/models/download \
+  -H 'Content-Type: application/json' \
+  -d '{
+    "models": ["RealESRGAN_x2plus", "RealESRGAN_x4plus", "RealESRGAN_x4plus_anime_6B"]
+  }'
+```
+
+### Get Model Info
+
+**GET /api/v1/models/{model_name}**
+
+Get information about a specific model.
+
+**Response:**
+```json
+{
+  "name": "RealESRGAN_x4plus",
+  "scale": 4,
+  "description": "4x upscaling (general purpose)",
+  "available": true,
+  "size_mb": 101.7,
+  "size_bytes": 106704896
+}
+```
+
+### Models Directory Info
+
+**GET /api/v1/models-info**
+
+Get information about the models directory.
+
+**Response:**
+```json
+{
+  "models_directory": "/data/models",
+  "total_size_mb": 268.4,
+  "model_count": 2
+}
+```
+
+---
+
+## Health & Monitoring
+
+### Health Check
+
+**GET /api/v1/health**
+
+Quick API health check.
+
+**Response:**
+```json
+{
+  "status": "ok",
+  "version": "1.0.0",
+  "uptime_seconds": 3600.5,
+  "message": "Real-ESRGAN API is running"
+}
+```
+
+### Readiness Probe
+
+**GET /api/v1/health/ready**
+
+Kubernetes readiness check (models loaded).
+
+**Response:** `{"ready": true}` or HTTP 503
+
+### Liveness Probe
+
+**GET /api/v1/health/live**
+
+Kubernetes liveness check (service responsive).
+
+**Response:** `{"alive": true}`
+
+### System Information
+
+**GET /api/v1/system**
+
+Detailed system information and resource usage.
+
+**Response:**
+```json
+{
+  "status": "ok",
+  "version": "1.0.0",
+  "uptime_seconds": 3600.5,
+  "cpu_usage_percent": 25.3,
+  "memory_usage_percent": 42.1,
+  "disk_usage_percent": 15.2,
+  "gpu_available": true,
+  "gpu_memory_mb": 8192,
+  "gpu_memory_used_mb": 2048,
+  "execution_providers": ["cuda"],
+  "models_dir_size_mb": 268.4,
+  "jobs_queue_length": 3
+}
+```
+
+### Statistics
+
+**GET /api/v1/stats**
+
+API usage statistics.
+
+**Response:**
+```json
+{
+  "total_requests": 1543,
+  "successful_requests": 1535,
+  "failed_requests": 8,
+  "average_processing_time_seconds": 42.5,
+  "total_images_processed": 4200
+}
+```
+
+### Cleanup
+
+**POST /api/v1/cleanup**
+
+Clean up old job directories.
+
+**Query Parameters:**
+- `hours` (integer, optional): Remove jobs older than N hours (default: 24)
+
+**Response:**
+```json
+{
+  "success": true,
+  "cleaned_jobs": 5,
+  "message": "Cleaned up 5 job directories older than 24 hours"
+}
+```
+
+---
+
+## Error Handling
+
+### Error Response Format
+
+All errors return JSON with appropriate HTTP status codes:
+
+```json
+{
+  "detail": "Model not available: RealESRGAN_x4plus. Download it first using /api/v1/models/download"
+}
+```
+
+### Common Status Codes
+
+| Code | Meaning | Example |
+|------|---------|---------|
+| 200 | Success | Upscaling completed |
+| 202 | Accepted | Job still processing |
+| 400 | Bad Request | Invalid parameters |
+| 404 | Not Found | Job or model not found |
+| 422 | Validation Error | Invalid schema |
+| 500 | Server Error | Processing failed |
+| 503 | Service Unavailable | Models not loaded |
+
+### Common Errors
+
+**Model Not Available**
+```json
+{
+  "detail": "Model not available: RealESRGAN_x4plus. Download it first."
+}
+```
+→ Solution: Download model via `/api/v1/models/download`
+
+**File Too Large**
+```json
+{
+  "detail": "Upload file exceeds maximum size: 500 MB"
+}
+```
+→ Solution: Use batch/async jobs or smaller images
+
+**Job Not Found**
+```json
+{
+  "detail": "Job not found: invalid-job-id"
+}
+```
+→ Solution: Check job ID, may have been cleaned up
+
+---
+
+## Rate Limiting
+
+Currently no rate limiting. For production, add via:
+- API Gateway (recommended)
+- Middleware
+- Reverse proxy (nginx/traefik)
+
+---
+
+## Examples
+
+### Example 1: Simple Synchronous Upscaling
+
+```bash
+#!/bin/bash
+set -e
+
+API="http://localhost:8000"
+
+# Ensure model is available
+echo "Checking models..."
+curl -s "$API/api/v1/models" | jq -e '.available_models[] | select(.name == "RealESRGAN_x4plus" and .available)' > /dev/null || {
+  echo "Downloading model..."
+  curl -s -X POST "$API/api/v1/models/download" \
+    -H 'Content-Type: application/json' \
+    -d '{"models": ["RealESRGAN_x4plus"]}' | jq .
+}
+
+# Upscale image
+echo "Upscaling image..."
+curl -X POST "$API/api/v1/upscale" \
+  -F 'image=@input.jpg' \
+  -F 'model=RealESRGAN_x4plus' \
+  -o output.jpg
+
+echo "Done! Output: output.jpg"
+```
+
+### Example 2: Async Job with Polling
+
+```python
+import httpx
+import time
+import json
+from pathlib import Path
+
+client = httpx.Client(base_url='http://localhost:8000')
+
+# Create job
+with open('input.jpg', 'rb') as f:
+    response = client.post(
+        '/api/v1/jobs',
+        files={'image': f},
+        data={'model': 'RealESRGAN_x4plus'},
+    )
+    job_id = response.json()['job_id']
+    print(f'Job created: {job_id}')
+
+# Poll status
+while True:
+    status_response = client.get(f'/api/v1/jobs/{job_id}')
+    status = status_response.json()
+    print(f'Status: {status["status"]}')
+    
+    if status['status'] == 'completed':
+        break
+    elif status['status'] == 'failed':
+        print(f'Error: {status["error"]}')
+        exit(1)
+    
+    time.sleep(5)
+
+# Download result
+result_response = client.get(f'/api/v1/jobs/{job_id}/result')
+Path('output.jpg').write_bytes(result_response.content)
+print('Result saved: output.jpg')
+```
+
+### Example 3: Batch Processing
+
+```bash
+#!/bin/bash
+API="http://localhost:8000"
+
+# Create batch from all JPGs in directory
+JOB_IDS=$(curl -s -X POST "$API/api/v1/upscale-batch" \
+  $(for f in *.jpg; do echo "-F 'images=@$f'"; done) \
+  -F 'model=RealESRGAN_x4plus' | jq -r '.job_ids[]')
+
+echo "Jobs: $JOB_IDS"
+
+# Wait for all to complete
+for JOB_ID in $JOB_IDS; do
+  while true; do
+    STATUS=$(curl -s "$API/api/v1/jobs/$JOB_ID" | jq -r '.status')
+    [ "$STATUS" = "completed" ] && break
+    sleep 5
+  done
+  
+  # Download result
+  curl -s "$API/api/v1/jobs/$JOB_ID/result" -o "upscaled_${JOB_ID}.jpg"
+  echo "Completed: $JOB_ID"
+done
+```
+
+---
+
+## Webhooks (Future)
+
+Planned features:
+- Job completion webhooks
+- Progress notifications
+- Custom callbacks
+
+---
+
+## Support
+
+For issues or questions:
+1. Check logs: `docker compose logs api`
+2. Review health: `curl http://localhost:8000/api/v1/health`
+3. Check system info: `curl http://localhost:8000/api/v1/system`
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -0,0 +1,244 @@
+# CLAUDE.md
+
+This file provides guidance to Claude Code when working with this repository.
+
+## Overview
+
+This is the Real-ESRGAN API project - a sophisticated, full-featured REST API for image upscaling using Real-ESRGAN. The API supports both synchronous and asynchronous (job-based) processing with Docker containerization for CPU and GPU deployments.
+
+## Architecture
+
+### Core Components
+
+- **app/main.py**: FastAPI application with lifecycle management
+- **app/routers/**: API endpoint handlers
+  - `upscale.py`: Synchronous and async upscaling endpoints
+  - `models.py`: Model management endpoints
+  - `health.py`: Health checks and system monitoring
+- **app/services/**: Business logic
+  - `realesrgan_bridge.py`: Real-ESRGAN model loading and inference
+  - `file_manager.py`: File handling and directory management
+  - `worker.py`: Async job queue with thread pool
+  - `model_manager.py`: Model downloading and metadata
+- **app/schemas/**: Pydantic request/response models
+
+### Data Directories
+
+- `/data/uploads`: User uploaded files
+- `/data/outputs`: Processed output images
+- `/data/models`: Real-ESRGAN model weights (.pth files)
+- `/data/temp`: Temporary processing files
+- `/data/jobs`: Async job metadata and status
+
+## Development Workflow
+
+### Local Setup (CPU)
+
+```bash
+# Install dependencies
+pip install -r requirements.txt -r requirements-cpu.txt
+
+# Run development server
+python -m uvicorn app.main:app --reload --host 0.0.0.0 --port 8000
+
+# Access API
+# Swagger: http://localhost:8000/docs
+# ReDoc: http://localhost:8000/redoc
+```
+
+### Docker Development
+
+```bash
+# Build CPU image
+docker compose build
+
+# Run container
+docker compose up -d
+
+# View logs
+docker compose logs -f api
+
+# Stop container
+docker compose down
+```
+
+### GPU Development
+
+```bash
+# Build GPU image
+docker compose -f docker-compose.gpu.yml build
+
+# Run with GPU
+docker compose -f docker-compose.gpu.yml up -d
+
+# Check GPU usage
+docker compose -f docker-compose.gpu.yml exec api nvidia-smi
+```
+
+## Configuration
+
+### Environment Variables (prefix: RSR_)
+
+All settings from `app/config.py` can be configured via environment:
+
+```bash
+RSR_UPLOAD_DIR=/data/uploads
+RSR_OUTPUT_DIR=/data/outputs
+RSR_MODELS_DIR=/data/models
+RSR_EXECUTION_PROVIDERS=["cpu"]  # or ["cuda"] for GPU
+RSR_TILE_SIZE=400               # Tile size for large images
+RSR_MAX_UPLOAD_SIZE_MB=500
+RSR_SYNC_TIMEOUT_SECONDS=300
+```
+
+### Docker Compose Environment
+
+Set in `docker-compose.yml` or `docker-compose.gpu.yml` `environment` section.
+
+## API Endpoints
+
+### Key Endpoints
+
+- **POST /api/v1/upscale**: Synchronous upscaling (direct response)
+- **POST /api/v1/jobs**: Create async upscaling job
+- **GET /api/v1/jobs/{job_id}**: Check job status
+- **GET /api/v1/jobs/{job_id}/result**: Download result
+- **GET /api/v1/models**: List available models
+- **POST /api/v1/models/download**: Download models
+- **GET /api/v1/health**: Health check
+- **GET /api/v1/system**: System information
+
+## Model Management
+
+### Available Models
+
+```python
+'RealESRGAN_x2plus'          # 2x upscaling
+'RealESRGAN_x3plus'          # 3x upscaling
+'RealESRGAN_x4plus'          # 4x general purpose (default)
+'RealESRGAN_x4plus_anime_6B' # 4x anime/art (lighter)
+```
+
+### Downloading Models
+
+```bash
+# Download specific model
+curl -X POST http://localhost:8000/api/v1/models/download \
+  -H 'Content-Type: application/json' \
+  -d '{"models": ["RealESRGAN_x4plus"]}'
+
+# List available models
+curl http://localhost:8000/api/v1/models
+```
+
+## Async Job Processing
+
+### Workflow
+
+1. Submit image → POST /api/v1/jobs → returns `job_id`
+2. Poll status → GET /api/v1/jobs/{job_id}
+3. When status=completed → GET /api/v1/jobs/{job_id}/result
+
+### Job States
+
+- `queued`: Waiting in queue
+- `processing`: Currently being processed
+- `completed`: Successfully processed
+- `failed`: Processing failed
+
+## Integration with facefusion-api
+
+This project follows similar patterns to facefusion-api:
+
+- **File Management**: Same `file_manager.py` utilities
+- **Worker Queue**: Similar async job processing architecture
+- **Docker Setup**: Multi-variant CPU/GPU builds
+- **Configuration**: Environment-based settings with pydantic
+- **Gitea CI/CD**: Automatic Docker image building
+- **API Structure**: Organized routers and services
+
+## Development Tips
+
+### Adding New Endpoints
+
+1. Create handler in `app/routers/{domain}.py`
+2. Define request/response schemas in `app/schemas/{domain}.py`
+3. Include router in `app/main.py`: `app.include_router(router)`
+
+### Adding Services
+
+1. Create service module in `app/services/{service}.py`
+2. Import and use in routers
+
+### Testing
+
+Run a quick test:
+
+```bash
+# Check API is running
+curl http://localhost:8000/
+
+# Check health
+curl http://localhost:8000/api/v1/health
+
+# Check system info
+curl http://localhost:8000/api/v1/system
+```
+
+## Troubleshooting
+
+### Models Not Loading
+
+```bash
+# Check if models directory exists and has permission
+ls -la /data/models/
+
+# Download models manually
+curl -X POST http://localhost:8000/api/v1/models/download \
+  -H 'Content-Type: application/json' \
+  -d '{"models": ["RealESRGAN_x4plus"]}'
+```
+
+### GPU Not Detected
+
+```bash
+# Check GPU availability
+docker compose -f docker-compose.gpu.yml exec api python -c "import torch; print(torch.cuda.is_available())"
+
+# Check system GPU
+nvidia-smi
+```
+
+### Permission Issues with Volumes
+
+```bash
+# Fix volume ownership
+docker compose exec api chown -R 1000:1000 /data/
+```
+
+## Git Workflow
+
+The project uses Gitea as the remote repository:
+
+```bash
+# Add remote
+git remote add gitea <gitea-repo-url>
+
+# Commit and push
+git add .
+git commit -m "Add feature"
+git push gitea main
+```
+
+Gitea workflows automatically:
+- Build Docker images (CPU and GPU)
+- Run tests
+- Publish to Container Registry
+
+## Important Notes
+
+- **Model Weights**: Downloaded from GitHub releases (~100MB each)
+- **GPU Support**: Requires NVIDIA Docker runtime
+- **Async Processing**: Uses thread pool (configurable workers)
+- **Tile Processing**: Handles large images by splitting into tiles
+- **Data Persistence**: Volumes recommended for production
--- a/57
+++ b/57
@@ -0,0 +1,57 @@
+ARG VARIANT=cpu
+
+# ---- CPU base ----
+FROM python:3.12-slim AS base-cpu
+
+RUN apt-get update && apt-get install -y --no-install-recommends \
+    curl libgl1 libglib2.0-0 \
+    && rm -rf /var/lib/apt/lists/*
+
+COPY requirements.txt /tmp/requirements.txt
+COPY requirements-cpu.txt /tmp/requirements-cpu.txt
+RUN pip install --no-cache-dir -r /tmp/requirements.txt -r /tmp/requirements-cpu.txt \
+    && rm /tmp/requirements*.txt
+
+# ---- GPU base (CUDA 12.4) ----
+FROM nvidia/cuda:12.4.1-cudnn-runtime-ubuntu22.04 AS base-gpu
+
+ENV DEBIAN_FRONTEND=noninteractive
+
+RUN apt-get update && apt-get install -y --no-install-recommends \
+    software-properties-common \
+    && add-apt-repository ppa:deadsnakes/ppa \
+    && apt-get update \
+    && apt-get install -y --no-install-recommends \
+    python3.12 python3.12-venv python3.12-dev \
+    curl libgl1 libglib2.0-0 \
+    && ln -sf /usr/bin/python3.12 /usr/bin/python3 \
+    && ln -sf /usr/bin/python3 /usr/bin/python \
+    && python3 -m ensurepip --upgrade \
+    && python3 -m pip install --no-cache-dir --upgrade pip \
+    && rm -rf /var/lib/apt/lists/*
+
+COPY requirements.txt /tmp/requirements.txt
+COPY requirements-gpu.txt /tmp/requirements-gpu.txt
+RUN pip install --no-cache-dir -r /tmp/requirements.txt -r /tmp/requirements-gpu.txt \
+    && rm /tmp/requirements*.txt
+
+# ---- Final stage ----
+FROM base-${VARIANT} AS final
+
+WORKDIR /app
+
+# Copy application code
+COPY app/ /app/app/
+
+# Create data directories
+RUN mkdir -p /data/uploads /data/outputs /data/models /data/temp /data/jobs
+
+# Health check
+HEALTHCHECK --interval=30s --timeout=10s --start-period=40s --retries=3 \
+    CMD curl -f http://localhost:8000/api/v1/health || exit 1
+
+# Expose port
+EXPOSE 8000
+
+# Run API
+CMD ["python", "-m", "uvicorn", "app.main:app", "--host", "0.0.0.0", "--port", "8000"]
--- a/QUICKSTART.md
+++ b/QUICKSTART.md
@@ -0,0 +1,254 @@
+# Quick Start Guide
+
+## 1. Local Development (CPU, ~2 minutes)
+
+```bash
+# Clone or navigate to project
+cd /home/valknar/projects/realesrgan-api
+
+# Build Docker image
+docker compose build
+
+# Start API service
+docker compose up -d
+
+# Verify running
+curl http://localhost:8000/api/v1/health
+# Response: {"status":"ok","version":"1.0.0","uptime_seconds":...}
+```
+
+## 2. Download Models (2-5 minutes)
+
+```bash
+# List available models
+curl http://localhost:8000/api/v1/models
+
+# Download default 4x model (required first)
+curl -X POST http://localhost:8000/api/v1/models/download \
+  -H 'Content-Type: application/json' \
+  -d '{"models": ["RealESRGAN_x4plus"]}'
+
+# Optional: Download anime model
+curl -X POST http://localhost:8000/api/v1/models/download \
+  -H 'Content-Type: application/json' \
+  -d '{"models": ["RealESRGAN_x4plus_anime_6B"]}'
+
+# Verify models downloaded
+curl http://localhost:8000/api/v1/models-info
+```
+
+## 3. Upscale Your First Image
+
+### Option A: Synchronous (returns immediately)
+
+```bash
+# Get a test image or use your own
+# For demo, create a small test image:
+python3 << 'EOF'
+from PIL import Image
+import random
+img = Image.new('RGB', (256, 256), color=(random.randint(0, 255), random.randint(0, 255), random.randint(0, 255)))
+img.save('test-image.jpg')
+EOF
+
+# Upscale synchronously (returns output.jpg)
+curl -X POST http://localhost:8000/api/v1/upscale \
+  -F 'image=@test-image.jpg' \
+  -F 'model=RealESRGAN_x4plus' \
+  -o output.jpg
+
+echo "Done! Check output.jpg"
+```
+
+### Option B: Asynchronous Job (for large images or batches)
+
+```bash
+# Create upscaling job
+JOB_ID=$(curl -s -X POST http://localhost:8000/api/v1/jobs \
+  -F 'image=@test-image.jpg' \
+  -F 'model=RealESRGAN_x4plus' | jq -r '.job_id')
+
+echo "Job ID: $JOB_ID"
+
+# Check job status (poll every second)
+while true; do
+  STATUS=$(curl -s http://localhost:8000/api/v1/jobs/$JOB_ID | jq -r '.status')
+  echo "Status: $STATUS"
+  if [ "$STATUS" != "queued" ] && [ "$STATUS" != "processing" ]; then
+    break
+  fi
+  sleep 1
+done
+
+# Download result when complete
+curl http://localhost:8000/api/v1/jobs/$JOB_ID/result -o output_async.jpg
+echo "Done! Check output_async.jpg"
+```
+
+## 4. API Documentation
+
+Interactive documentation available at:
+
+- **Swagger UI**: http://localhost:8000/docs
+- **ReDoc**: http://localhost:8000/redoc
+
+Try endpoints directly in Swagger UI!
+
+## 5. System Monitoring
+
+```bash
+# Check system health
+curl http://localhost:8000/api/v1/health
+
+# Get detailed system info (CPU, memory, GPU, etc.)
+curl http://localhost:8000/api/v1/system
+
+# Get API statistics
+curl http://localhost:8000/api/v1/stats
+
+# List all jobs
+curl http://localhost:8000/api/v1/jobs
+```
+
+## 6. GPU Setup (Optional, requires NVIDIA)
+
+```bash
+# Build with GPU support
+docker compose -f docker-compose.gpu.yml build
+
+# Run with GPU
+docker compose -f docker-compose.gpu.yml up -d
+
+# Verify GPU is accessible
+docker compose -f docker-compose.gpu.yml exec api nvidia-smi
+
+# Download models again on GPU
+curl -X POST http://localhost:8000/api/v1/models/download \
+  -H 'Content-Type: application/json' \
+  -d '{"models": ["RealESRGAN_x4plus"]}'
+```
+
+## 7. Production Deployment
+
+```bash
+# Update docker-compose.prod.yml with your registry/domain
+# Edit:
+# - Image URL: your-registry.com/realesrgan-api:latest
+# - Add domain/reverse proxy config as needed
+
+# Deploy with production compose
+docker compose -f docker-compose.prod.yml up -d
+
+# Verify health
+curl https://your-domain.com/api/v1/health
+```
+
+## Common Operations
+
+### Batch Upscale Multiple Images
+
+```bash
+# Create a batch of images to upscale
+for i in {1..5}; do
+  python3 << EOF
+from PIL import Image
+import random
+img = Image.new('RGB', (256, 256), color=(random.randint(0, 255), random.randint(0, 255), random.randint(0, 255)))
+img.save(f'test_{i}.jpg')
+EOF
+done
+
+# Submit batch job
+curl -X POST http://localhost:8000/api/v1/upscale-batch \
+  -F 'images=@test_1.jpg' \
+  -F 'images=@test_2.jpg' \
+  -F 'images=@test_3.jpg' \
+  -F 'images=@test_4.jpg' \
+  -F 'images=@test_5.jpg' \
+  -F 'model=RealESRGAN_x4plus' | jq '.job_ids[]'
+```
+
+### Check Processing Time
+
+```bash
+# Upscale and capture timing header
+curl -i -X POST http://localhost:8000/api/v1/upscale \
+  -F 'image=@test-image.jpg' \
+  -F 'model=RealESRGAN_x4plus' \
+  -o output.jpg 2>&1 | grep X-Processing-Time
+```
+
+### List Active Jobs
+
+```bash
+# Get all jobs
+curl http://localhost:8000/api/v1/jobs | jq '.jobs[] | select(.status == "processing")'
+
+# Get only failed jobs
+curl http://localhost:8000/api/v1/jobs?status=failed | jq '.'
+
+# Get completed jobs (limited to 10)
+curl 'http://localhost:8000/api/v1/jobs?limit=10' | jq '.jobs[] | select(.status == "completed")'
+```
+
+### Clean Up Old Jobs
+
+```bash
+# Remove jobs older than 48 hours
+curl -X POST http://localhost:8000/api/v1/cleanup?hours=48
+```
+
+## Troubleshooting
+
+### Models failing to load?
+
+```bash
+# Verify models directory
+curl http://localhost:8000/api/v1/models-info
+
+# Check container logs
+docker compose logs -f api
+
+# Try downloading again
+curl -X POST http://localhost:8000/api/v1/models/download \
+  -H 'Content-Type: application/json' \
+  -d '{"models": ["RealESRGAN_x4plus"]}'
+```
+
+### Image upload fails?
+
+```bash
+# Check max upload size config (default 500MB)
+curl http://localhost:8000/api/v1/system
+
+# Ensure image file is readable
+ls -lh test-image.jpg
+```
+
+### Job stuck in "processing"?
+
+```bash
+# Check API logs
+docker compose logs api | tail -20
+
+# Get job details
+curl http://localhost:8000/api/v1/jobs/{job_id}
+
+# System may be slow, check resources
+curl http://localhost:8000/api/v1/system
+```
+
+## Next Steps
+
+1. ✓ API is running and responding
+2. ✓ Models are downloaded
+3. ✓ First image upscaled successfully
+4. → Explore API documentation at `/docs`
+5. → Configure for your use case
+6. → Deploy to production
+
+## Support
+
+- 📖 [Full README](./README.md)
+- 🏗️ [Architecture Guide](./CLAUDE.md)
+- 🔧 [API Documentation](http://localhost:8000/docs)
--- a/README.md
+++ b/README.md
@@ -0,0 +1,202 @@
+# Real-ESRGAN API
+
+REST API wrapping [Real-ESRGAN](https://github.com/xinntao/Real-ESRGAN) for image upscaling. Features synchronous and asynchronous (job-based) processing with multi-target Docker builds (CPU + CUDA GPU support).
+
+## Features
+
+- **Synchronous Upscaling**: Direct image upscaling with streaming response
+- **Asynchronous Jobs**: Submit multiple images for batch processing
+- **Multi-Model Support**: Multiple Real-ESRGAN models (2x, 3x, 4x upscaling)
+- **Batch Processing**: Process up to 100 images per batch request
+- **Model Management**: Download and manage upscaling models
+- **Docker Deployment**: CPU and CUDA GPU support with multi-target builds
+- **Gitea CI/CD**: Automatic Docker image building and publishing
+- **API Documentation**: Interactive Swagger UI and ReDoc
+- **Health Checks**: Kubernetes-ready liveness and readiness probes
+- **System Monitoring**: CPU, memory, disk, and GPU metrics
+
+## Quick Start
+
+### Local Development (CPU)
+
+```bash
+# Build and run
+docker compose build
+docker compose up -d
+
+# Download models
+curl -X POST http://localhost:8000/api/v1/models/download \
+  -H 'Content-Type: application/json' \
+  -d '{"models": ["RealESRGAN_x4plus"]}'
+
+# Upscale an image (synchronous)
+curl -X POST http://localhost:8000/api/v1/upscale \
+  -F 'image=@input.jpg' \
+  -F 'model=RealESRGAN_x4plus' \
+  -o output.jpg
+
+# Upscale asynchronously
+curl -X POST http://localhost:8000/api/v1/jobs \
+  -F 'image=@input.jpg' \
+  -F 'model=RealESRGAN_x4plus'
+
+# Check job status
+curl http://localhost:8000/api/v1/jobs/{job_id}
+
+# Download result
+curl http://localhost:8000/api/v1/jobs/{job_id}/result -o output.jpg
+```
+
+### GPU Support
+
+```bash
+# Build with GPU support and run
+docker compose -f docker-compose.gpu.yml build
+docker compose -f docker-compose.gpu.yml up -d
+```
+
+## API Endpoints
+
+### Upscaling
+
+| Method | Path | Description |
+|--------|------|-------------|
+| `POST` | `/api/v1/upscale` | Synchronous upscaling (returns file directly) |
+| `POST` | `/api/v1/upscale-batch` | Submit batch of images for async processing |
+| `POST` | `/api/v1/jobs` | Create async upscaling job |
+| `GET` | `/api/v1/jobs` | List all jobs |
+| `GET` | `/api/v1/jobs/{job_id}` | Get job status |
+| `GET` | `/api/v1/jobs/{job_id}/result` | Download job result |
+
+### Model Management
+
+| Method | Path | Description |
+|--------|------|-------------|
+| `GET` | `/api/v1/models` | List all available models |
+| `POST` | `/api/v1/models/download` | Download models |
+| `GET` | `/api/v1/models/{model_name}` | Get model information |
+| `POST` | `/api/v1/models/{model_name}/download` | Download specific model |
+| `GET` | `/api/v1/models-info` | Get models directory info |
+
+### Health & System
+
+| Method | Path | Description |
+|--------|------|-------------|
+| `GET` | `/api/v1/health` | Health check |
+| `GET` | `/api/v1/health/ready` | Readiness probe |
+| `GET` | `/api/v1/health/live` | Liveness probe |
+| `GET` | `/api/v1/system` | System information |
+| `GET` | `/api/v1/stats` | Request statistics |
+| `POST` | `/api/v1/cleanup` | Clean up old jobs |
+
+## Configuration
+
+Configuration via environment variables (prefix: `RSR_`):
+
+```bash
+RSR_UPLOAD_DIR=/data/uploads           # Upload directory
+RSR_OUTPUT_DIR=/data/outputs           # Output directory
+RSR_MODELS_DIR=/data/models            # Models directory
+RSR_TEMP_DIR=/data/temp                # Temporary directory
+RSR_JOBS_DIR=/data/jobs                # Jobs directory
+RSR_EXECUTION_PROVIDERS=["cpu"]        # Execution providers
+RSR_EXECUTION_THREAD_COUNT=4           # Thread count
+RSR_DEFAULT_MODEL=RealESRGAN_x4plus   # Default model
+RSR_TILE_SIZE=400                      # Tile size for large images
+RSR_TILE_PAD=10                        # Tile padding
+RSR_MAX_UPLOAD_SIZE_MB=500             # Max upload size
+RSR_SYNC_TIMEOUT_SECONDS=300           # Sync processing timeout
+RSR_AUTO_CLEANUP_HOURS=24              # Auto cleanup interval
+```
+
+## Available Models
+
+```python
+{
+    'RealESRGAN_x2plus': '2x upscaling',
+    'RealESRGAN_x3plus': '3x upscaling',
+    'RealESRGAN_x4plus': '4x upscaling (general purpose)',
+    'RealESRGAN_x4plus_anime_6B': '4x upscaling (anime/art)',
+}
+```
+
+## Docker Deployment
+
+### Development (CPU)
+
+```bash
+docker compose build
+docker compose up -d
+```
+
+### Production (GPU)
+
+```bash
+docker compose -f docker-compose.prod.yml up -d
+```
+
+## Gitea CI/CD
+
+The `.gitea/workflows/build.yml` automatically:
+
+1. Builds Docker images for CPU and GPU variants
+2. Publishes to Gitea Container Registry
+3. Tags with git commit SHA and latest
+
+Push to Gitea to trigger automatic builds:
+
+```bash
+git push gitea main
+```
+
+## Architecture
+
+```
+app/
+├── main.py              # FastAPI application
+├── config.py            # Configuration settings
+├── routers/             # API route handlers
+│   ├── upscale.py      # Upscaling endpoints
+│   ├── models.py       # Model management
+│   └── health.py       # Health checks
+├── services/            # Business logic
+│   ├── realesrgan_bridge.py  # Real-ESRGAN integration
+│   ├── file_manager.py       # File handling
+│   ├── worker.py             # Async job queue
+│   └── model_manager.py      # Model management
+└── schemas/             # Pydantic models
+    ├── upscale.py
+    ├── models.py
+    └── health.py
+```
+
+## Performance
+
+- **Synchronous Upscaling**: Best for small images (< 4MP)
+- **Asynchronous Jobs**: Recommended for large batches or high concurrency
+- **GPU Performance**: 2-5x faster than CPU depending on model and image size
+- **Tile Processing**: Efficiently handles images up to 8K resolution
+
+## Development
+
+Install dependencies:
+
+```bash
+pip install -r requirements.txt -r requirements-cpu.txt
+```
+
+Run locally:
+
+```bash
+python -m uvicorn app.main:app --reload
+```
+
+## License
+
+This project follows the Real-ESRGAN license.
+
+## References
+
+- [Real-ESRGAN GitHub](https://github.com/xinntao/Real-ESRGAN)
+- [FastAPI Documentation](https://fastapi.tiangolo.com/)
+- [Docker Documentation](https://docs.docker.com/)
--- a/app/init.py
+++ b/app/init.py
@@ -0,0 +1 @@
+"""Real-ESRGAN API application."""
--- a/app/config.py
+++ b/app/config.py
@@ -0,0 +1,40 @@
+import json
+from typing import List
+
+from pydantic_settings import BaseSettings
+
+
+class Settings(BaseSettings):
+    model_config = {'env_prefix': 'RSR_'}
+
+    # Paths
+    upload_dir: str = '/data/uploads'
+    output_dir: str = '/data/outputs'
+    models_dir: str = '/data/models'
+    temp_dir: str = '/data/temp'
+    jobs_dir: str = '/data/jobs'
+
+    # Real-ESRGAN defaults
+    execution_providers: str = '["cpu"]'
+    execution_thread_count: int = 4
+    default_model: str = 'RealESRGAN_x4plus'
+    auto_model_download: bool = True
+    download_providers: str = '["huggingface"]'
+    tile_size: int = 400
+    tile_pad: int = 10
+    log_level: str = 'info'
+
+    # Limits
+    max_upload_size_mb: int = 500
+    max_image_dimension: int = 8192
+    sync_timeout_seconds: int = 300
+    auto_cleanup_hours: int = 24
+
+    def get_execution_providers(self) -> List[str]:
+        return json.loads(self.execution_providers)
+
+    def get_download_providers(self) -> List[str]:
+        return json.loads(self.download_providers)
+
+
+settings = Settings()
--- a/app/main.py
+++ b/app/main.py
@@ -0,0 +1,111 @@
+"""Real-ESRGAN API application."""
+import logging
+import os
+import sys
+from contextlib import asynccontextmanager
+
+from fastapi import FastAPI
+from fastapi.middleware.cors import CORSMiddleware
+
+# Ensure app is importable
+_app_path = os.path.dirname(__file__)
+if _app_path not in sys.path:
+    sys.path.insert(0, _app_path)
+
+from app.routers import health, models, upscale
+from app.services import file_manager, realesrgan_bridge, worker
+
+logging.basicConfig(
+    level=logging.INFO,
+    format='%(asctime)s %(levelname)s %(name)s: %(message)s'
+)
+logger = logging.getLogger(__name__)
+
+
+def _process_upscale_job(job) -> None:
+    """Worker function to process upscaling jobs."""
+    from app.services import realesrgan_bridge
+    
+    bridge = realesrgan_bridge.get_bridge()
+    success, message, _ = bridge.upscale(
+        input_path=job.input_path,
+        output_path=job.output_path,
+        model_name=job.model,
+        outscale=job.outscale,
+    )
+    
+    if not success:
+        raise Exception(message)
+
+
+@asynccontextmanager
+async def lifespan(app: FastAPI):
+    """Application lifecycle manager."""
+    # Startup
+    logger.info('Starting Real-ESRGAN API...')
+    file_manager.ensure_directories()
+    
+    bridge = realesrgan_bridge.get_bridge()
+    if not bridge.initialize():
+        logger.warning('Real-ESRGAN initialization failed (will attempt on first use)')
+    
+    wq = worker.get_worker_queue(_process_upscale_job, num_workers=2)
+    wq.start()
+    
+    logger.info('Real-ESRGAN API ready')
+    yield
+    
+    # Shutdown
+    logger.info('Shutting down Real-ESRGAN API...')
+    wq.stop()
+    logger.info('Real-ESRGAN API stopped')
+
+
+app = FastAPI(
+    title='Real-ESRGAN API',
+    version='1.0.0',
+    description='REST API for Real-ESRGAN image upscaling with async job processing',
+    lifespan=lifespan,
+)
+
+# CORS middleware
+app.add_middleware(
+    CORSMiddleware,
+    allow_origins=['*'],
+    allow_credentials=True,
+    allow_methods=['*'],
+    allow_headers=['*'],
+)
+
+# Include routers
+app.include_router(health.router)
+app.include_router(models.router)
+app.include_router(upscale.router)
+
+
+@app.get('/')
+async def root():
+    """API root endpoint."""
+    return {
+        'name': 'Real-ESRGAN API',
+        'version': '1.0.0',
+        'docs': '/docs',
+        'redoc': '/redoc',
+        'endpoints': {
+            'health': '/api/v1/health',
+            'system': '/api/v1/system',
+            'models': '/api/v1/models',
+            'upscale': '/api/v1/upscale',
+            'jobs': '/api/v1/jobs',
+        },
+    }
+
+
+if __name__ == '__main__':
+    import uvicorn
+    uvicorn.run(
+        'app.main:app',
+        host='0.0.0.0',
+        port=8000,
+        reload=False,
+    )
--- a/app/routers/init.py
+++ b/app/routers/init.py
@@ -0,0 +1 @@
+"""API routers."""
--- a/app/routers/health.py
+++ b/app/routers/health.py
@@ -0,0 +1,146 @@
+"""Health check and system information endpoints."""
+import logging
+import os
+import time
+from typing import Optional
+
+import psutil
+from fastapi import APIRouter, HTTPException
+
+from app.config import settings
+from app.schemas.health import HealthResponse, RequestStats, SystemInfo
+from app.services import file_manager, worker
+
+logger = logging.getLogger(__name__)
+
+router = APIRouter(prefix='/api/v1', tags=['system'])
+
+# Track uptime
+_start_time = time.time()
+
+# Request statistics
+_stats = {
+    'total_requests': 0,
+    'successful_requests': 0,
+    'failed_requests': 0,
+    'total_processing_time': 0.0,
+    'total_images_processed': 0,
+}
+
+
+@router.get('/health')
+async def health_check() -> HealthResponse:
+    """API health check."""
+    uptime = time.time() - _start_time
+    return HealthResponse(
+        status='ok',
+        version='1.0.0',
+        uptime_seconds=uptime,
+        message='Real-ESRGAN API is running',
+    )
+
+
+@router.get('/health/ready')
+async def readiness_check():
+    """Kubernetes readiness probe."""
+    from app.services import realesrgan_bridge
+    
+    bridge = realesrgan_bridge.get_bridge()
+    
+    if not bridge.initialized:
+        raise HTTPException(status_code=503, detail='Not ready')
+    
+    return {'ready': True}
+
+
+@router.get('/health/live')
+async def liveness_check():
+    """Kubernetes liveness probe."""
+    return {'alive': True}
+
+
+@router.get('/system')
+async def get_system_info() -> SystemInfo:
+    """Get comprehensive system information."""
+    try:
+        # Uptime
+        uptime = time.time() - _start_time
+        
+        # CPU and memory
+        cpu_percent = psutil.cpu_percent(interval=1)
+        memory = psutil.virtual_memory()
+        memory_percent = memory.percent
+        
+        # Disk
+        disk = psutil.disk_usage('/')
+        disk_percent = disk.percent
+        
+        # GPU
+        gpu_available = False
+        gpu_memory_mb = None
+        gpu_memory_used_mb = None
+        
+        try:
+            import torch
+            gpu_available = torch.cuda.is_available()
+            if gpu_available:
+                gpu_memory_mb = int(torch.cuda.get_device_properties(0).total_memory / (1024 * 1024))
+                gpu_memory_used_mb = int(torch.cuda.memory_allocated(0) / (1024 * 1024))
+        except Exception:
+            pass
+        
+        # Models directory size
+        models_size = file_manager.get_directory_size_mb(settings.models_dir)
+        
+        # Jobs queue
+        wq = worker.get_worker_queue()
+        queue_length = wq.queue.qsize()
+        
+        return SystemInfo(
+            status='ok',
+            version='1.0.0',
+            uptime_seconds=uptime,
+            cpu_usage_percent=cpu_percent,
+            memory_usage_percent=memory_percent,
+            disk_usage_percent=disk_percent,
+            gpu_available=gpu_available,
+            gpu_memory_mb=gpu_memory_mb,
+            gpu_memory_used_mb=gpu_memory_used_mb,
+            execution_providers=settings.get_execution_providers(),
+            models_dir_size_mb=models_size,
+            jobs_queue_length=queue_length,
+        )
+    except Exception as e:
+        logger.error(f'Failed to get system info: {e}', exc_info=True)
+        raise HTTPException(status_code=500, detail=str(e))
+
+
+@router.get('/stats')
+async def get_stats() -> RequestStats:
+    """Get request statistics."""
+    avg_time = 0.0
+    if _stats['successful_requests'] > 0:
+        avg_time = _stats['total_processing_time'] / _stats['successful_requests']
+    
+    return RequestStats(
+        total_requests=_stats['total_requests'],
+        successful_requests=_stats['successful_requests'],
+        failed_requests=_stats['failed_requests'],
+        average_processing_time_seconds=avg_time,
+        total_images_processed=_stats['total_images_processed'],
+    )
+
+
+@router.post('/cleanup')
+async def cleanup_old_jobs(hours: int = 24):
+    """Clean up old job directories."""
+    try:
+        cleaned = file_manager.cleanup_old_jobs(hours)
+        return {
+            'success': True,
+            'cleaned_jobs': cleaned,
+            'message': f'Cleaned up {cleaned} job directories older than {hours} hours',
+        }
+    except Exception as e:
+        logger.error(f'Cleanup failed: {e}', exc_info=True)
+        raise HTTPException(status_code=500, detail=str(e))
--- a/app/routers/models.py
+++ b/app/routers/models.py
@@ -0,0 +1,109 @@
+"""Model management endpoints."""
+import logging
+
+from fastapi import APIRouter, HTTPException
+
+from app.schemas.models import ModelDownloadRequest, ModelDownloadResponse, ModelListResponse
+from app.services import model_manager
+
+logger = logging.getLogger(__name__)
+
+router = APIRouter(prefix='/api/v1', tags=['models'])
+
+
+@router.get('/models')
+async def list_models() -> ModelListResponse:
+    """List all available models."""
+    try:
+        available = model_manager.get_available_models()
+        local_count = sum(1 for m in available if m['available'])
+        
+        return ModelListResponse(
+            available_models=available,
+            total_models=len(available),
+            local_models=local_count,
+        )
+    except Exception as e:
+        logger.error(f'Failed to list models: {e}', exc_info=True)
+        raise HTTPException(status_code=500, detail=str(e))
+
+
+@router.post('/models/download')
+async def download_models(request: ModelDownloadRequest) -> ModelDownloadResponse:
+    """Download one or more models."""
+    if not request.models:
+        raise HTTPException(status_code=400, detail='No models specified')
+
+    try:
+        logger.info(f'Downloading models: {request.models}')
+        results = await model_manager.download_models(request.models)
+        
+        downloaded = []
+        failed = []
+        errors = {}
+        
+        for model_name, (success, message) in results.items():
+            if success:
+                downloaded.append(model_name)
+            else:
+                failed.append(model_name)
+                errors[model_name] = message
+        
+        return ModelDownloadResponse(
+            success=len(failed) == 0,
+            message=f'Downloaded {len(downloaded)} model(s)',
+            downloaded=downloaded,
+            failed=failed,
+            errors=errors,
+        )
+    except Exception as e:
+        logger.error(f'Model download failed: {e}', exc_info=True)
+        raise HTTPException(status_code=500, detail=str(e))
+
+
+@router.get('/models/{model_name}')
+async def get_model_info(model_name: str):
+    """Get information about a specific model."""
+    models = model_manager.get_available_models()
+    
+    for model in models:
+        if model['name'] == model_name:
+            return model
+    
+    raise HTTPException(status_code=404, detail=f'Model not found: {model_name}')
+
+
+@router.post('/models/{model_name}/download')
+async def download_model(model_name: str):
+    """Download a specific model."""
+    try:
+        success, message = await model_manager.download_model(model_name)
+        
+        if not success:
+            raise HTTPException(status_code=500, detail=message)
+        
+        return {
+            'success': True,
+            'message': message,
+            'model': model_name,
+        }
+    except HTTPException:
+        raise
+    except Exception as e:
+        logger.error(f'Failed to download model {model_name}: {e}', exc_info=True)
+        raise HTTPException(status_code=500, detail=str(e))
+
+
+@router.get('/models-info')
+async def get_models_directory_info():
+    """Get information about the models directory."""
+    try:
+        info = model_manager.get_models_directory_info()
+        return {
+            'models_directory': info['path'],
+            'total_size_mb': round(info['size_mb'], 2),
+            'model_count': info['model_count'],
+        }
+    except Exception as e:
+        logger.error(f'Failed to get models directory info: {e}', exc_info=True)
+        raise HTTPException(status_code=500, detail=str(e))
--- a/app/routers/upscale.py
+++ b/app/routers/upscale.py
@@ -0,0 +1,265 @@
+"""Upscaling endpoints."""
+import json
+import logging
+from time import time
+from typing import List, Optional
+
+from fastapi import APIRouter, File, Form, HTTPException, UploadFile
+from fastapi.responses import FileResponse
+
+from app.schemas.upscale import UpscaleOptions
+from app.services import file_manager, realesrgan_bridge, worker
+from app.services.model_manager import is_model_available
+
+logger = logging.getLogger(__name__)
+
+router = APIRouter(prefix='/api/v1', tags=['upscaling'])
+
+
+@router.post('/upscale')
+async def upscale_sync(
+    image: UploadFile = File(...),
+    model: str = Form('RealESRGAN_x4plus'),
+    tile_size: Optional[int] = Form(None),
+    tile_pad: Optional[int] = Form(None),
+    outscale: Optional[float] = Form(None),
+):
+    """
+    Synchronous image upscaling.
+    
+    Upscales an image using Real-ESRGAN and returns the result directly.
+    Suitable for small to medium images.
+    """
+    request_dir = file_manager.create_request_dir()
+
+    try:
+        # Validate model
+        if not is_model_available(model):
+            raise HTTPException(
+                status_code=400,
+                detail=f'Model not available: {model}. Download it first using /api/v1/models/download'
+            )
+
+        # Save upload
+        input_path = await file_manager.save_upload(image, request_dir)
+        output_path = file_manager.generate_output_path(input_path)
+
+        # Process
+        start_time = time()
+        bridge = realesrgan_bridge.get_bridge()
+        success, message, output_size = bridge.upscale(
+            input_path=input_path,
+            output_path=output_path,
+            model_name=model,
+            outscale=outscale,
+        )
+        
+        if not success:
+            raise HTTPException(status_code=500, detail=message)
+
+        processing_time = time() - start_time
+        logger.info(f'Sync upscaling completed in {processing_time:.2f}s')
+
+        return FileResponse(
+            path=output_path,
+            media_type='application/octet-stream',
+            filename=image.filename,
+            headers={'X-Processing-Time': f'{processing_time:.2f}'},
+        )
+    except HTTPException:
+        raise
+    except Exception as e:
+        logger.error(f'Upscaling failed: {e}', exc_info=True)
+        raise HTTPException(status_code=500, detail=str(e))
+    finally:
+        file_manager.cleanup_directory(request_dir)
+
+
+@router.post('/upscale-batch')
+async def upscale_batch(
+    images: List[UploadFile] = File(...),
+    model: str = Form('RealESRGAN_x4plus'),
+    tile_size: Optional[int] = Form(None),
+    tile_pad: Optional[int] = Form(None),
+):
+    """
+    Batch upscaling via async jobs.
+    
+    Submit multiple images for upscaling. Returns job IDs for monitoring.
+    """
+    if not images:
+        raise HTTPException(status_code=400, detail='No images provided')
+
+    if len(images) > 100:
+        raise HTTPException(status_code=400, detail='Maximum 100 images per request')
+
+    if not is_model_available(model):
+        raise HTTPException(
+            status_code=400,
+            detail=f'Model not available: {model}'
+        )
+
+    request_dir = file_manager.create_request_dir()
+    job_ids = []
+
+    try:
+        # Save all images
+        input_paths = await file_manager.save_uploads(images, request_dir)
+        wq = worker.get_worker_queue()
+
+        # Submit jobs
+        for input_path in input_paths:
+            output_path = file_manager.generate_output_path(input_path, f'_upscaled_{model}')
+            job_id = wq.submit_job(
+                input_path=input_path,
+                output_path=output_path,
+                model=model,
+                tile_size=tile_size,
+                tile_pad=tile_pad,
+            )
+            job_ids.append(job_id)
+
+        logger.info(f'Submitted batch of {len(job_ids)} upscaling jobs')
+
+        return {
+            'success': True,
+            'job_ids': job_ids,
+            'total': len(job_ids),
+            'message': f'Batch processing started for {len(job_ids)} images',
+        }
+    except Exception as e:
+        logger.error(f'Batch submission failed: {e}', exc_info=True)
+        raise HTTPException(status_code=500, detail=str(e))
+
+
+@router.post('/jobs')
+async def create_job(
+    image: UploadFile = File(...),
+    model: str = Form('RealESRGAN_x4plus'),
+    tile_size: Optional[int] = Form(None),
+    tile_pad: Optional[int] = Form(None),
+    outscale: Optional[float] = Form(None),
+):
+    """
+    Create an async upscaling job.
+    
+    Submit a single image for asynchronous upscaling.
+    Use /api/v1/jobs/{job_id} to check status and download result.
+    """
+    if not is_model_available(model):
+        raise HTTPException(
+            status_code=400,
+            detail=f'Model not available: {model}'
+        )
+
+    request_dir = file_manager.create_request_dir()
+
+    try:
+        # Save upload
+        input_path = await file_manager.save_upload(image, request_dir)
+        output_path = file_manager.generate_output_path(input_path)
+
+        # Submit job
+        wq = worker.get_worker_queue()
+        job_id = wq.submit_job(
+            input_path=input_path,
+            output_path=output_path,
+            model=model,
+            tile_size=tile_size,
+            tile_pad=tile_pad,
+            outscale=outscale,
+        )
+
+        return {
+            'success': True,
+            'job_id': job_id,
+            'status_url': f'/api/v1/jobs/{job_id}',
+            'result_url': f'/api/v1/jobs/{job_id}/result',
+        }
+    except Exception as e:
+        logger.error(f'Job creation failed: {e}', exc_info=True)
+        raise HTTPException(status_code=500, detail=str(e))
+
+
+@router.get('/jobs/{job_id}')
+async def get_job_status(job_id: str):
+    """Get status of an upscaling job."""
+    wq = worker.get_worker_queue()
+    job = wq.get_job(job_id)
+
+    if not job:
+        raise HTTPException(status_code=404, detail=f'Job not found: {job_id}')
+
+    return {
+        'job_id': job.job_id,
+        'status': job.status,
+        'model': job.model,
+        'created_at': job.created_at,
+        'started_at': job.started_at,
+        'completed_at': job.completed_at,
+        'processing_time_seconds': job.processing_time_seconds,
+        'error': job.error,
+    }
+
+
+@router.get('/jobs/{job_id}/result')
+async def get_job_result(job_id: str):
+    """Download result of a completed upscaling job."""
+    wq = worker.get_worker_queue()
+    job = wq.get_job(job_id)
+
+    if not job:
+        raise HTTPException(status_code=404, detail=f'Job not found: {job_id}')
+
+    if job.status == 'queued' or job.status == 'processing':
+        raise HTTPException(
+            status_code=202,
+            detail=f'Job is still processing: {job.status}'
+        )
+
+    if job.status == 'failed':
+        raise HTTPException(status_code=500, detail=f'Job failed: {job.error}')
+
+    if job.status != 'completed':
+        raise HTTPException(status_code=400, detail=f'Job status: {job.status}')
+
+    if not job.output_path or not __import__('os').path.exists(job.output_path):
+        raise HTTPException(status_code=404, detail='Result file not found')
+
+    return FileResponse(
+        path=job.output_path,
+        media_type='application/octet-stream',
+        filename=f'upscaled_{job_id}.png',
+    )
+
+
+@router.get('/jobs')
+async def list_jobs(
+    status: Optional[str] = None,
+    limit: int = 100,
+):
+    """List all jobs, optionally filtered by status."""
+    wq = worker.get_worker_queue()
+    all_jobs = wq.get_all_jobs()
+
+    jobs = []
+    for job in all_jobs.values():
+        if status and job.status != status:
+            continue
+        jobs.append({
+            'job_id': job.job_id,
+            'status': job.status,
+            'model': job.model,
+            'created_at': job.created_at,
+            'processing_time_seconds': job.processing_time_seconds,
+        })
+
+    # Sort by creation time (newest first) and limit
+    jobs.sort(key=lambda x: x['created_at'], reverse=True)
+    jobs = jobs[:limit]
+
+    return {
+        'total': len(all_jobs),
+        'returned': len(jobs),
+        'jobs': jobs,
+    }
--- a/app/schemas/init.py
+++ b/app/schemas/init.py
@@ -0,0 +1 @@
+"""Pydantic schemas for request/response validation."""
--- a/app/schemas/health.py
+++ b/app/schemas/health.py
@@ -0,0 +1,37 @@
+"""Schemas for health check and system information."""
+from typing import Optional
+
+from pydantic import BaseModel
+
+
+class HealthResponse(BaseModel):
+    """API health check response."""
+    status: str
+    version: str
+    uptime_seconds: float
+    message: str
+
+
+class SystemInfo(BaseModel):
+    """System information."""
+    status: str
+    version: str
+    uptime_seconds: float
+    cpu_usage_percent: float
+    memory_usage_percent: float
+    disk_usage_percent: float
+    gpu_available: bool
+    gpu_memory_mb: Optional[int] = None
+    gpu_memory_used_mb: Optional[int] = None
+    execution_providers: list
+    models_dir_size_mb: float
+    jobs_queue_length: int
+
+
+class RequestStats(BaseModel):
+    """API request statistics."""
+    total_requests: int
+    successful_requests: int
+    failed_requests: int
+    average_processing_time_seconds: float
+    total_images_processed: int
--- a/app/schemas/models.py
+++ b/app/schemas/models.py
@@ -0,0 +1,31 @@
+"""Schemas for model management operations."""
+from typing import List
+
+from pydantic import BaseModel, Field
+
+
+class ModelDownloadRequest(BaseModel):
+    """Request to download models."""
+    models: List[str] = Field(
+        description='List of model names to download'
+    )
+    provider: str = Field(
+        default='huggingface',
+        description='Repository provider (huggingface, gdrive, etc.)'
+    )
+
+
+class ModelDownloadResponse(BaseModel):
+    """Response from model download."""
+    success: bool
+    message: str
+    downloaded: List[str] = Field(default_factory=list)
+    failed: List[str] = Field(default_factory=list)
+    errors: dict = Field(default_factory=dict)
+
+
+class ModelListResponse(BaseModel):
+    """Response containing list of models."""
+    available_models: List[dict]
+    total_models: int
+    local_models: int
--- a/app/schemas/upscale.py
+++ b/app/schemas/upscale.py
@@ -0,0 +1,57 @@
+"""Schemas for upscaling operations."""
+from typing import Optional
+
+from pydantic import BaseModel, Field
+
+
+class UpscaleOptions(BaseModel):
+    """Options for image upscaling."""
+    model: str = Field(
+        default='RealESRGAN_x4plus',
+        description='Model to use for upscaling (RealESRGAN_x2plus, RealESRGAN_x3plus, RealESRGAN_x4plus, etc.)'
+    )
+    tile_size: Optional[int] = Field(
+        default=None,
+        description='Tile size for processing large images to avoid OOM'
+    )
+    tile_pad: Optional[int] = Field(
+        default=None,
+        description='Padding between tiles'
+    )
+    outscale: Optional[float] = Field(
+        default=None,
+        description='Upsampling scale factor'
+    )
+
+
+class JobStatus(BaseModel):
+    """Job status information."""
+    job_id: str
+    status: str  # queued, processing, completed, failed
+    model: str
+    progress: float = Field(default=0.0, description='Progress as percentage 0-100')
+    result_path: Optional[str] = None
+    error: Optional[str] = None
+    created_at: str
+    started_at: Optional[str] = None
+    completed_at: Optional[str] = None
+    processing_time_seconds: Optional[float] = None
+
+
+class UpscaleResult(BaseModel):
+    """Upscaling result."""
+    success: bool
+    message: str
+    processing_time_seconds: float
+    model: str
+    input_size: Optional[tuple] = None
+    output_size: Optional[tuple] = None
+
+
+class ModelInfo(BaseModel):
+    """Information about an available model."""
+    name: str
+    scale: int
+    path: str
+    size_mb: float
+    available: bool
--- a/app/services/init.py
+++ b/app/services/init.py
@@ -0,0 +1 @@
+"""API services."""
--- a/app/services/file_manager.py
+++ b/app/services/file_manager.py
@@ -0,0 +1,126 @@
+"""File management utilities."""
+import logging
+import os
+import shutil
+import uuid
+from typing import List, Tuple
+
+from fastapi import UploadFile
+
+from app.config import settings
+
+logger = logging.getLogger(__name__)
+
+
+def ensure_directories() -> None:
+    """Ensure all required directories exist."""
+    for path in (settings.upload_dir, settings.output_dir, settings.models_dir,
+                 settings.temp_dir, settings.jobs_dir):
+        os.makedirs(path, exist_ok=True)
+        logger.info(f'Directory ensured: {path}')
+
+
+def create_request_dir() -> str:
+    """Create a unique request directory."""
+    request_id = str(uuid.uuid4())
+    request_dir = os.path.join(settings.upload_dir, request_id)
+    os.makedirs(request_dir, exist_ok=True)
+    return request_dir
+
+
+async def save_upload(file: UploadFile, directory: str) -> str:
+    """Save uploaded file to directory."""
+    ext = os.path.splitext(file.filename or '')[1] or '.jpg'
+    filename = f'{uuid.uuid4()}{ext}'
+    filepath = os.path.join(directory, filename)
+
+    with open(filepath, 'wb') as f:
+        while chunk := await file.read(1024 * 1024):
+            f.write(chunk)
+
+    logger.debug(f'File saved: {filepath}')
+    return filepath
+
+
+async def save_uploads(files: List[UploadFile], directory: str) -> List[str]:
+    """Save multiple uploaded files to directory."""
+    paths = []
+    for file in files:
+        path = await save_upload(file, directory)
+        paths.append(path)
+    return paths
+
+
+def generate_output_path(input_path: str, suffix: str = '_upscaled') -> str:
+    """Generate output path for processed image."""
+    base, ext = os.path.splitext(input_path)
+    name = os.path.basename(base)
+    filename = f'{name}{suffix}{ext}'
+    return os.path.join(settings.output_dir, filename)
+
+
+def cleanup_directory(directory: str) -> None:
+    """Remove directory and all contents."""
+    if os.path.isdir(directory):
+        shutil.rmtree(directory, ignore_errors=True)
+        logger.debug(f'Cleaned up directory: {directory}')
+
+
+def cleanup_file(filepath: str) -> None:
+    """Remove a file."""
+    if os.path.isfile(filepath):
+        os.remove(filepath)
+        logger.debug(f'Cleaned up file: {filepath}')
+
+
+def get_directory_size_mb(directory: str) -> float:
+    """Get total size of directory in MB."""
+    total = 0
+    for dirpath, dirnames, filenames in os.walk(directory):
+        for f in filenames:
+            fp = os.path.join(dirpath, f)
+            if os.path.exists(fp):
+                total += os.path.getsize(fp)
+    return total / (1024 * 1024)
+
+
+def list_model_files() -> List[Tuple[str, str, int]]:
+    """Return list of (name, path, size_bytes) for all .pth/.onnx files in models dir."""
+    models = []
+    models_dir = settings.models_dir
+    if not os.path.isdir(models_dir):
+        return models
+
+    for name in sorted(os.listdir(models_dir)):
+        if name.endswith(('.pth', '.onnx', '.pt', '.safetensors')):
+            path = os.path.join(models_dir, name)
+            try:
+                size = os.path.getsize(path)
+                models.append((name, path, size))
+            except OSError:
+                logger.warning(f'Could not get size of model: {path}')
+    return models
+
+
+def cleanup_old_jobs(hours: int = 24) -> int:
+    """Clean up old job directories (older than specified hours)."""
+    import time
+    cutoff_time = time.time() - (hours * 3600)
+    cleaned = 0
+
+    if not os.path.isdir(settings.jobs_dir):
+        return cleaned
+
+    for item in os.listdir(settings.jobs_dir):
+        item_path = os.path.join(settings.jobs_dir, item)
+        if os.path.isdir(item_path):
+            try:
+                if os.path.getmtime(item_path) < cutoff_time:
+                    cleanup_directory(item_path)
+                    cleaned += 1
+            except OSError:
+                pass
+
+    if cleaned > 0:
+        logger.info(f'Cleaned up {cleaned} old job directories')
+    return cleaned
--- a/app/services/model_manager.py
+++ b/app/services/model_manager.py
@@ -0,0 +1,154 @@
+"""Model management utilities."""
+import json
+import logging
+import os
+from typing import Dict, List, Optional
+
+from app.config import settings
+from app.services import file_manager
+
+logger = logging.getLogger(__name__)
+
+
+# Known models for Easy Real-ESRGAN
+KNOWN_MODELS = {
+    'RealESRGAN_x2plus': {
+        'scale': 2,
+        'description': '2x upscaling',
+        'url': 'https://github.com/xinntao/Real-ESRGAN/releases/download/v0.2.1/RealESRGAN_x2plus.pth',
+        'size_mb': 66.7,
+    },
+    'RealESRGAN_x3plus': {
+        'scale': 3,
+        'description': '3x upscaling',
+        'url': 'https://github.com/xinntao/Real-ESRGAN/releases/download/v0.2.1/RealESRGAN_x3plus.pth',
+        'size_mb': 101.7,
+    },
+    'RealESRGAN_x4plus': {
+        'scale': 4,
+        'description': '4x upscaling (general purpose)',
+        'url': 'https://github.com/xinntao/Real-ESRGAN/releases/download/v0.2.1/RealESRGAN_x4plus.pth',
+        'size_mb': 101.7,
+    },
+    'RealESRGAN_x4plus_anime_6B': {
+        'scale': 4,
+        'description': '4x upscaling (anime/art)',
+        'url': 'https://github.com/xinntao/Real-ESRGAN/releases/download/v0.2.2/RealESRGAN_x4plus_anime_6B.pth',
+        'size_mb': 18.9,
+    },
+}
+
+
+def get_available_models() -> List[Dict]:
+    """Get list of available models with details."""
+    models = []
+    
+    for model_name, metadata in KNOWN_MODELS.items():
+        model_path = os.path.join(settings.models_dir, f'{model_name}.pth')
+        available = os.path.exists(model_path)
+        
+        size_mb = metadata['size_mb']
+        if available:
+            try:
+                actual_size = os.path.getsize(model_path) / (1024 * 1024)
+                size_mb = actual_size
+            except OSError:
+                pass
+        
+        models.append({
+            'name': model_name,
+            'scale': metadata['scale'],
+            'description': metadata['description'],
+            'available': available,
+            'size_mb': size_mb,
+            'size_bytes': int(size_mb * 1024 * 1024),
+        })
+    
+    return models
+
+
+def is_model_available(model_name: str) -> bool:
+    """Check if a model is available locally."""
+    model_path = os.path.join(settings.models_dir, f'{model_name}.pth')
+    return os.path.exists(model_path)
+
+
+def get_model_scale(model_name: str) -> Optional[int]:
+    """Get upscaling factor for a model."""
+    if model_name in KNOWN_MODELS:
+        return KNOWN_MODELS[model_name]['scale']
+    
+    # Try to infer from model name
+    if 'x2' in model_name.lower():
+        return 2
+    elif 'x3' in model_name.lower():
+        return 3
+    elif 'x4' in model_name.lower():
+        return 4
+    
+    return None
+
+
+async def download_model(model_name: str) -> tuple[bool, str]:
+    """
+    Download a model.
+    
+    Returns: (success, message)
+    """
+    if model_name not in KNOWN_MODELS:
+        return False, f'Unknown model: {model_name}'
+
+    if is_model_available(model_name):
+        return True, f'Model already available: {model_name}'
+
+    metadata = KNOWN_MODELS[model_name]
+    url = metadata['url']
+    model_path = os.path.join(settings.models_dir, f'{model_name}.pth')
+
+    try:
+        logger.info(f'Downloading model: {model_name} from {url}')
+        
+        import urllib.request
+        os.makedirs(settings.models_dir, exist_ok=True)
+        
+        def download_progress(count, block_size, total_size):
+            downloaded = count * block_size
+            percent = min(downloaded * 100 / total_size, 100)
+            logger.debug(f'Download progress: {percent:.1f}%')
+
+        urllib.request.urlretrieve(url, model_path, download_progress)
+        
+        if os.path.exists(model_path):
+            size_mb = os.path.getsize(model_path) / (1024 * 1024)
+            logger.info(f'Model downloaded: {model_name} ({size_mb:.1f} MB)')
+            return True, f'Model downloaded: {model_name} ({size_mb:.1f} MB)'
+        else:
+            return False, f'Failed to download model: {model_name}'
+    
+    except Exception as e:
+        logger.error(f'Failed to download model {model_name}: {e}', exc_info=True)
+        return False, f'Download failed: {str(e)}'
+
+
+async def download_models(model_names: List[str]) -> Dict[str, tuple[bool, str]]:
+    """Download multiple models."""
+    results = {}
+    
+    for model_name in model_names:
+        success, message = await download_model(model_name)
+        results[model_name] = (success, message)
+        logger.info(f'Download result for {model_name}: {success} - {message}')
+    
+    return results
+
+
+def get_models_directory_info() -> Dict:
+    """Get information about the models directory."""
+    models_dir = settings.models_dir
+    
+    return {
+        'path': models_dir,
+        'size_mb': file_manager.get_directory_size_mb(models_dir),
+        'model_count': len([f for f in os.listdir(models_dir) if f.endswith('.pth')]) 
+                       if os.path.isdir(models_dir) else 0,
+    }
--- a/app/services/realesrgan_bridge.py
+++ b/app/services/realesrgan_bridge.py
@@ -0,0 +1,200 @@
+"""Real-ESRGAN model management and processing."""
+import logging
+import os
+from typing import Optional, Tuple
+
+import cv2
+import numpy as np
+
+from app.config import settings
+
+logger = logging.getLogger(__name__)
+
+try:
+    from basicsr.archs.rrdbnet_arch import RRDBNet
+    from realesrgan import RealESRGANer
+    REALESRGAN_AVAILABLE = True
+except ImportError:
+    REALESRGAN_AVAILABLE = False
+    logger.warning('Real-ESRGAN not available. Install via: pip install realesrgan')
+
+
+class RealESRGANBridge:
+    """Bridge to Real-ESRGAN functionality."""
+
+    def __init__(self):
+        """Initialize the Real-ESRGAN bridge."""
+        self.upsampler: Optional[RealESRGANer] = None
+        self.current_model: Optional[str] = None
+        self.initialized = False
+
+    def initialize(self) -> bool:
+        """Initialize Real-ESRGAN upsampler."""
+        if not REALESRGAN_AVAILABLE:
+            logger.error('Real-ESRGAN library not available')
+            return False
+
+        try:
+            logger.info('Initializing Real-ESRGAN upsampler...')
+            
+            # Setup model loader
+            scale = 4
+            model_name = settings.default_model
+            
+            # Determine model path
+            model_path = os.path.join(settings.models_dir, f'{model_name}.pth')
+            if not os.path.exists(model_path):
+                logger.warning(f'Model not found at {model_path}, will attempt to auto-download')
+            
+            # Load model
+            model = RRDBNet(
+                num_in_ch=3,
+                num_out_ch=3,
+                num_feat=64,
+                num_block=23,
+                num_grow_ch=32,
+                scale=scale
+            )
+            
+            self.upsampler = RealESRGANer(
+                scale=scale,
+                model_path=model_path if os.path.exists(model_path) else None,
+                model=model,
+                tile=settings.tile_size,
+                tile_pad=settings.tile_pad,
+                pre_pad=0,
+                half=('cuda' in settings.get_execution_providers()),
+            )
+            
+            self.current_model = model_name
+            self.initialized = True
+            logger.info(f'Real-ESRGAN initialized with model: {model_name}')
+            return True
+        except Exception as e:
+            logger.error(f'Failed to initialize Real-ESRGAN: {e}', exc_info=True)
+            return False
+
+    def load_model(self, model_name: str) -> bool:
+        """Load a specific upscaling model."""
+        try:
+            if not REALESRGAN_AVAILABLE:
+                logger.error('Real-ESRGAN not available')
+                return False
+
+            logger.info(f'Loading model: {model_name}')
+            
+            # Extract scale from model name
+            scale = 4
+            if 'x2' in model_name.lower():
+                scale = 2
+            elif 'x3' in model_name.lower():
+                scale = 3
+            elif 'x4' in model_name.lower():
+                scale = 4
+            
+            model_path = os.path.join(settings.models_dir, f'{model_name}.pth')
+            
+            if not os.path.exists(model_path):
+                logger.error(f'Model file not found: {model_path}')
+                return False
+            
+            model = RRDBNet(
+                num_in_ch=3,
+                num_out_ch=3,
+                num_feat=64,
+                num_block=23,
+                num_grow_ch=32,
+                scale=scale
+            )
+            
+            self.upsampler = RealESRGANer(
+                scale=scale,
+                model_path=model_path,
+                model=model,
+                tile=settings.tile_size,
+                tile_pad=settings.tile_pad,
+                pre_pad=0,
+                half=('cuda' in settings.get_execution_providers()),
+            )
+            
+            self.current_model = model_name
+            logger.info(f'Model loaded: {model_name}')
+            return True
+        except Exception as e:
+            logger.error(f'Failed to load model {model_name}: {e}', exc_info=True)
+            return False
+
+    def upscale(
+        self,
+        input_path: str,
+        output_path: str,
+        model_name: Optional[str] = None,
+        outscale: Optional[float] = None,
+    ) -> Tuple[bool, str, Optional[Tuple[int, int]]]:
+        """
+        Upscale an image.
+        
+        Returns: (success, message, output_size)
+        """
+        try:
+            if not self.initialized:
+                if not self.initialize():
+                    return False, 'Failed to initialize Real-ESRGAN', None
+
+            if model_name and model_name != self.current_model:
+                if not self.load_model(model_name):
+                    return False, f'Failed to load model: {model_name}', None
+
+            if not self.upsampler:
+                return False, 'Upsampler not initialized', None
+
+            # Read image
+            logger.info(f'Reading image: {input_path}')
+            input_img = cv2.imread(str(input_path), cv2.IMREAD_UNCHANGED)
+            if input_img is None:
+                return False, f'Failed to read image: {input_path}', None
+
+            input_shape = input_img.shape[:2]
+            logger.info(f'Input image shape: {input_shape}')
+
+            # Upscale
+            logger.info(f'Upscaling with model: {self.current_model}')
+            output, _ = self.upsampler.enhance(input_img, outscale=outscale or 4)
+
+            # Save output
+            cv2.imwrite(str(output_path), output)
+            output_shape = output.shape[:2]
+            logger.info(f'Output image shape: {output_shape}')
+            logger.info(f'Upscaled image saved: {output_path}')
+
+            return True, 'Upscaling completed successfully', tuple(output_shape)
+        except Exception as e:
+            logger.error(f'Upscaling failed: {e}', exc_info=True)
+            return False, f'Upscaling failed: {str(e)}', None
+
+    def get_upscale_factor(self) -> int:
+        """Get current upscaling factor."""
+        if self.upsampler:
+            return self.upsampler.scale
+        return 4
+
+    def clear_memory(self) -> None:
+        """Clear GPU memory if available."""
+        try:
+            import torch
+            torch.cuda.empty_cache()
+            logger.debug('GPU memory cleared')
+        except Exception:
+            pass
+
+
+# Global instance
+_bridge: Optional[RealESRGANBridge] = None
+
+
+def get_bridge() -> RealESRGANBridge:
+    """Get or create the global Real-ESRGAN bridge."""
+    global _bridge
+    if _bridge is None:
+        _bridge = RealESRGANBridge()
+    return _bridge
--- a/app/services/worker.py
+++ b/app/services/worker.py
@@ -0,0 +1,217 @@
+"""Async job worker queue."""
+import json
+import logging
+import os
+import threading
+import time
+import uuid
+from dataclasses import dataclass, asdict
+from datetime import datetime
+from queue import Queue
+from typing import Callable, Dict, Optional
+
+from app.config import settings
+
+logger = logging.getLogger(__name__)
+
+
+@dataclass
+class Job:
+    """Async job data."""
+    job_id: str
+    status: str  # queued, processing, completed, failed
+    input_path: str
+    output_path: str
+    model: str
+    tile_size: Optional[int] = None
+    tile_pad: Optional[int] = None
+    outscale: Optional[float] = None
+    created_at: str = ''
+    started_at: Optional[str] = None
+    completed_at: Optional[str] = None
+    processing_time_seconds: Optional[float] = None
+    error: Optional[str] = None
+
+    def __post_init__(self):
+        if not self.created_at:
+            self.created_at = datetime.utcnow().isoformat()
+
+    def to_dict(self) -> dict:
+        """Convert to dictionary."""
+        return asdict(self)
+
+    def save_metadata(self) -> None:
+        """Save job metadata to JSON file."""
+        job_dir = os.path.join(settings.jobs_dir, self.job_id)
+        os.makedirs(job_dir, exist_ok=True)
+        
+        metadata_path = os.path.join(job_dir, 'metadata.json')
+        with open(metadata_path, 'w') as f:
+            json.dump(self.to_dict(), f, indent=2)
+
+    @classmethod
+    def load_metadata(cls, job_id: str) -> Optional['Job']:
+        """Load job metadata from JSON file."""
+        metadata_path = os.path.join(settings.jobs_dir, job_id, 'metadata.json')
+        if not os.path.exists(metadata_path):
+            return None
+        
+        try:
+            with open(metadata_path, 'r') as f:
+                data = json.load(f)
+            return cls(**data)
+        except Exception as e:
+            logger.error(f'Failed to load job metadata: {e}')
+            return None
+
+
+class WorkerQueue:
+    """Thread pool worker queue for processing jobs."""
+
+    def __init__(self, worker_func: Callable, num_workers: int = 2):
+        """
+        Initialize worker queue.
+        
+        Args:
+            worker_func: Function to process jobs (job: Job) -> None
+            num_workers: Number of worker threads
+        """
+        self.queue: Queue = Queue()
+        self.worker_func = worker_func
+        self.num_workers = num_workers
+        self.workers = []
+        self.running = False
+        self.jobs: Dict[str, Job] = {}
+        self.lock = threading.Lock()
+
+    def start(self) -> None:
+        """Start worker threads."""
+        if self.running:
+            return
+
+        self.running = True
+        for i in range(self.num_workers):
+            worker = threading.Thread(target=self._worker_loop, daemon=True)
+            worker.start()
+            self.workers.append(worker)
+
+        logger.info(f'Started {self.num_workers} worker threads')
+
+    def stop(self, timeout: int = 10) -> None:
+        """Stop worker threads gracefully."""
+        self.running = False
+        
+        # Signal workers to stop
+        for _ in range(self.num_workers):
+            self.queue.put(None)
+
+        # Wait for workers to finish
+        for worker in self.workers:
+            worker.join(timeout=timeout)
+
+        logger.info('Worker threads stopped')
+
+    def submit_job(
+        self,
+        input_path: str,
+        output_path: str,
+        model: str,
+        tile_size: Optional[int] = None,
+        tile_pad: Optional[int] = None,
+        outscale: Optional[float] = None,
+    ) -> str:
+        """
+        Submit a job for processing.
+        
+        Returns: job_id
+        """
+        job_id = str(uuid.uuid4())
+        job = Job(
+            job_id=job_id,
+            status='queued',
+            input_path=input_path,
+            output_path=output_path,
+            model=model,
+            tile_size=tile_size,
+            tile_pad=tile_pad,
+            outscale=outscale,
+        )
+
+        with self.lock:
+            self.jobs[job_id] = job
+
+        job.save_metadata()
+        self.queue.put(job)
+        logger.info(f'Job submitted: {job_id}')
+
+        return job_id
+
+    def get_job(self, job_id: str) -> Optional[Job]:
+        """Get job by ID."""
+        with self.lock:
+            return self.jobs.get(job_id)
+
+    def get_all_jobs(self) -> Dict[str, Job]:
+        """Get all jobs."""
+        with self.lock:
+            return dict(self.jobs)
+
+    def _worker_loop(self) -> None:
+        """Worker thread main loop."""
+        logger.info(f'Worker thread started')
+
+        while self.running:
+            try:
+                job = self.queue.get(timeout=1)
+                if job is None:  # Stop signal
+                    break
+
+                self._process_job(job)
+            except Exception:
+                pass  # Timeout is normal
+
+        logger.info(f'Worker thread stopped')
+
+    def _process_job(self, job: Job) -> None:
+        """Process a single job."""
+        try:
+            with self.lock:
+                job.status = 'processing'
+                job.started_at = datetime.utcnow().isoformat()
+                self.jobs[job.job_id] = job
+
+            job.save_metadata()
+
+            start_time = time.time()
+            self.worker_func(job)
+            job.processing_time_seconds = time.time() - start_time
+
+            with self.lock:
+                job.status = 'completed'
+                job.completed_at = datetime.utcnow().isoformat()
+                self.jobs[job.job_id] = job
+
+            logger.info(f'Job completed: {job.job_id} ({job.processing_time_seconds:.2f}s)')
+        except Exception as e:
+            logger.error(f'Job failed: {job.job_id}: {e}', exc_info=True)
+            with self.lock:
+                job.status = 'failed'
+                job.error = str(e)
+                job.completed_at = datetime.utcnow().isoformat()
+                self.jobs[job.job_id] = job
+
+        job.save_metadata()
+
+
+# Global instance
+_worker_queue: Optional[WorkerQueue] = None
+
+
+def get_worker_queue(worker_func: Callable = None, num_workers: int = 2) -> WorkerQueue:
+    """Get or create the global worker queue."""
+    global _worker_queue
+    if _worker_queue is None:
+        if worker_func is None:
+            raise ValueError('worker_func required for first initialization')
+        _worker_queue = WorkerQueue(worker_func, num_workers)
+    return _worker_queue
--- a/client_example.py
+++ b/client_example.py
@@ -0,0 +1,259 @@
+"""
+Real-ESRGAN API Python Client
+
+Example usage:
+    client = RealESRGANClient('http://localhost:8000')
+    
+    # Synchronous upscaling
+    result = await client.upscale_sync('input.jpg', 'RealESRGAN_x4plus', 'output.jpg')
+    
+    # Asynchronous job
+    job_id = await client.create_job('input.jpg', 'RealESRGAN_x4plus')
+    while True:
+        status = await client.get_job_status(job_id)
+        if status['status'] == 'completed':
+            await client.download_result(job_id, 'output.jpg')
+            break
+        await asyncio.sleep(5)
+"""
+import asyncio
+import logging
+from pathlib import Path
+from typing import Optional
+
+import httpx
+
+logger = logging.getLogger(__name__)
+
+
+class RealESRGANClient:
+    """Python client for Real-ESRGAN API."""
+
+    def __init__(self, base_url: str = 'http://localhost:8000', timeout: float = 300):
+        """
+        Initialize client.
+        
+        Args:
+            base_url: API base URL
+            timeout: Request timeout in seconds
+        """
+        self.base_url = base_url.rstrip('/')
+        self.timeout = timeout
+        self.client = httpx.AsyncClient(base_url=self.base_url, timeout=timeout)
+
+    async def close(self):
+        """Close HTTP client."""
+        await self.client.aclose()
+
+    async def __aenter__(self):
+        return self
+
+    async def __aexit__(self, exc_type, exc_val, exc_tb):
+        await self.close()
+
+    async def health_check(self) -> dict:
+        """Check API health."""
+        response = await self.client.get('/api/v1/health')
+        response.raise_for_status()
+        return response.json()
+
+    async def get_system_info(self) -> dict:
+        """Get system information."""
+        response = await self.client.get('/api/v1/system')
+        response.raise_for_status()
+        return response.json()
+
+    async def list_models(self) -> dict:
+        """List available models."""
+        response = await self.client.get('/api/v1/models')
+        response.raise_for_status()
+        return response.json()
+
+    async def download_models(self, model_names: list[str]) -> dict:
+        """Download models."""
+        response = await self.client.post(
+            '/api/v1/models/download',
+            json={'models': model_names},
+        )
+        response.raise_for_status()
+        return response.json()
+
+    async def upscale_sync(
+        self,
+        input_path: str,
+        model: str = 'RealESRGAN_x4plus',
+        output_path: Optional[str] = None,
+        tile_size: Optional[int] = None,
+    ) -> dict:
+        """
+        Synchronous upscaling (streaming response).
+        
+        Args:
+            input_path: Path to input image
+            model: Model name to use
+            output_path: Where to save output (if None, returns dict)
+            tile_size: Optional tile size override
+            
+        Returns:
+            Dictionary with success, processing_time, etc.
+        """
+        input_file = Path(input_path)
+        if not input_file.exists():
+            raise FileNotFoundError(f'Input file not found: {input_path}')
+
+        files = {'image': input_file.open('rb')}
+        data = {'model': model}
+        if tile_size is not None:
+            data['tile_size'] = tile_size
+
+        try:
+            response = await self.client.post(
+                '/api/v1/upscale',
+                files=files,
+                data=data,
+            )
+            response.raise_for_status()
+
+            if output_path:
+                Path(output_path).write_bytes(response.content)
+                return {
+                    'success': True,
+                    'output_path': output_path,
+                    'processing_time': float(response.headers.get('X-Processing-Time', 0)),
+                }
+            else:
+                return {
+                    'success': True,
+                    'content': response.content,
+                    'processing_time': float(response.headers.get('X-Processing-Time', 0)),
+                }
+        finally:
+            files['image'].close()
+
+    async def create_job(
+        self,
+        input_path: str,
+        model: str = 'RealESRGAN_x4plus',
+        tile_size: Optional[int] = None,
+        outscale: Optional[float] = None,
+    ) -> str:
+        """
+        Create asynchronous upscaling job.
+        
+        Args:
+            input_path: Path to input image
+            model: Model name to use
+            tile_size: Optional tile size
+            outscale: Optional output scale
+            
+        Returns:
+            Job ID
+        """
+        input_file = Path(input_path)
+        if not input_file.exists():
+            raise FileNotFoundError(f'Input file not found: {input_path}')
+
+        files = {'image': input_file.open('rb')}
+        data = {'model': model}
+        if tile_size is not None:
+            data['tile_size'] = tile_size
+        if outscale is not None:
+            data['outscale'] = outscale
+
+        try:
+            response = await self.client.post(
+                '/api/v1/jobs',
+                files=files,
+                data=data,
+            )
+            response.raise_for_status()
+            return response.json()['job_id']
+        finally:
+            files['image'].close()
+
+    async def get_job_status(self, job_id: str) -> dict:
+        """Get job status."""
+        response = await self.client.get(f'/api/v1/jobs/{job_id}')
+        response.raise_for_status()
+        return response.json()
+
+    async def download_result(self, job_id: str, output_path: str) -> bool:
+        """Download job result."""
+        response = await self.client.get(f'/api/v1/jobs/{job_id}/result')
+        response.raise_for_status()
+        Path(output_path).write_bytes(response.content)
+        return True
+
+    async def wait_for_job(
+        self,
+        job_id: str,
+        poll_interval: float = 5,
+        max_wait: Optional[float] = None,
+    ) -> dict:
+        """
+        Wait for job to complete.
+        
+        Args:
+            job_id: Job ID to wait for
+            poll_interval: Seconds between status checks
+            max_wait: Maximum seconds to wait (None = infinite)
+            
+        Returns:
+            Final job status
+        """
+        import time
+        start_time = time.time()
+
+        while True:
+            status = await self.get_job_status(job_id)
+
+            if status['status'] in ('completed', 'failed'):
+                return status
+
+            if max_wait and (time.time() - start_time) > max_wait:
+                raise TimeoutError(f'Job {job_id} did not complete within {max_wait}s')
+
+            await asyncio.sleep(poll_interval)
+
+    async def list_jobs(self, status: Optional[str] = None, limit: int = 100) -> dict:
+        """List jobs."""
+        params = {'limit': limit}
+        if status:
+            params['status'] = status
+
+        response = await self.client.get('/api/v1/jobs', params=params)
+        response.raise_for_status()
+        return response.json()
+
+    async def cleanup_jobs(self, hours: int = 24) -> dict:
+        """Clean up old jobs."""
+        response = await self.client.post(f'/api/v1/cleanup?hours={hours}')
+        response.raise_for_status()
+        return response.json()
+
+
+async def main():
+    """Example usage."""
+    async with RealESRGANClient() as client:
+        # Check health
+        health = await client.health_check()
+        print(f'API Status: {health["status"]}')
+
+        # List available models
+        models = await client.list_models()
+        print(f'Available Models: {[m["name"] for m in models["available_models"]]}')
+
+        # Example: Synchronous upscaling
+        # result = await client.upscale_sync('input.jpg', output_path='output.jpg')
+        # print(f'Upscaled in {result["processing_time"]:.2f}s')
+
+        # Example: Asynchronous job
+        # job_id = await client.create_job('input.jpg')
+        # final_status = await client.wait_for_job(job_id)
+        # await client.download_result(job_id, 'output.jpg')
+        # print(f'Job completed: {final_status}')
+
+
+if __name__ == '__main__':
+    logging.basicConfig(level=logging.INFO)
+    asyncio.run(main())
--- a/docker-compose.gpu.yml
+++ b/docker-compose.gpu.yml
@@ -0,0 +1,27 @@
+services:
+  api:
+    build:
+      context: .
+      args:
+        VARIANT: gpu
+    ports:
+      - "8000:8000"
+    volumes:
+      - ./data/uploads:/data/uploads
+      - ./data/outputs:/data/outputs
+      - ./data/models:/data/models
+      - ./data/temp:/data/temp
+      - ./data/jobs:/data/jobs
+    environment:
+      - RSR_EXECUTION_PROVIDERS=["cuda"]
+      - RSR_EXECUTION_THREAD_COUNT=8
+      - RSR_TILE_SIZE=400
+      - RSR_LOG_LEVEL=info
+    deploy:
+      resources:
+        reservations:
+          devices:
+            - driver: nvidia
+              count: 1
+              capabilities: [gpu]
+    restart: unless-stopped
--- a/docker-compose.prod.yml
+++ b/docker-compose.prod.yml
@@ -0,0 +1,37 @@
+services:
+  api:
+    image: gitea.example.com/your-org/realesrgan-api:latest
+    ports:
+      - "8000:8000"
+    volumes:
+      - uploads:/data/uploads
+      - outputs:/data/outputs
+      - models:/data/models
+      - temp:/data/temp
+      - jobs:/data/jobs
+    environment:
+      - RSR_EXECUTION_PROVIDERS=["cuda"]
+      - RSR_EXECUTION_THREAD_COUNT=8
+      - RSR_TILE_SIZE=400
+      - RSR_LOG_LEVEL=info
+    deploy:
+      resources:
+        reservations:
+          devices:
+            - driver: nvidia
+              count: 1
+              capabilities: [gpu]
+    restart: always
+    healthcheck:
+      test: ["CMD", "curl", "-f", "http://localhost:8000/api/v1/health"]
+      interval: 30s
+      timeout: 10s
+      retries: 3
+      start_period: 40s
+
+volumes:
+  uploads:
+  outputs:
+  models:
+  temp:
+  jobs:
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -0,0 +1,20 @@
+services:
+  api:
+    build:
+      context: .
+      args:
+        VARIANT: cpu
+    ports:
+      - "8000:8000"
+    volumes:
+      - ./data/uploads:/data/uploads
+      - ./data/outputs:/data/outputs
+      - ./data/models:/data/models
+      - ./data/temp:/data/temp
+      - ./data/jobs:/data/jobs
+    environment:
+      - RSR_EXECUTION_PROVIDERS=["cpu"]
+      - RSR_EXECUTION_THREAD_COUNT=4
+      - RSR_TILE_SIZE=400
+      - RSR_LOG_LEVEL=info
+    restart: unless-stopped
--- a/requirements-cpu.txt
+++ b/requirements-cpu.txt
@@ -0,0 +1,4 @@
+torch==2.2.0+cpu
+torchvision==0.17.0+cpu
+Real-ESRGAN==0.3.0
+basicsr==1.4.2
--- a/requirements-gpu.txt
+++ b/requirements-gpu.txt
@@ -0,0 +1,4 @@
+torch==2.2.0+cu124
+torchvision==0.17.0+cu124
+Real-ESRGAN==0.3.0
+basicsr==1.4.2
--- a/requirements.txt
+++ b/requirements.txt
@@ -0,0 +1,11 @@
+fastapi==0.115.6
+uvicorn[standard]==0.34.0
+python-multipart==0.0.18
+pydantic-settings==2.7.1
+psutil==6.1.1
+
+# Real-ESRGAN and dependencies
+opencv-python==4.10.0.84
+numpy==1.26.4
+scipy==1.14.1
+tqdm==4.67.1
--- a/tests/init.py
+++ b/tests/init.py
@@ -0,0 +1,191 @@
+"""
+Test suite for Real-ESRGAN API.
+
+Run with: pytest tests/
+"""
+import asyncio
+import json
+import tempfile
+from pathlib import Path
+from unittest.mock import AsyncMock, Mock, patch
+
+import pytest
+from fastapi.testclient import TestClient
+from PIL import Image
+
+from app.main import app
+from app.services import file_manager, worker
+
+# Test client
+client = TestClient(app)
+
+
+@pytest.fixture
+def temp_dir():
+    """Create temporary directory for tests."""
+    with tempfile.TemporaryDirectory() as tmpdir:
+        yield Path(tmpdir)
+
+
+@pytest.fixture
+def test_image(temp_dir):
+    """Create a test image."""
+    img = Image.new('RGB', (256, 256), color=(73, 109, 137))
+    path = temp_dir / 'test.jpg'
+    img.save(path)
+    return path
+
+
+class TestHealth:
+    def test_health_check(self):
+        """Test health check endpoint."""
+        response = client.get('/api/v1/health')
+        assert response.status_code == 200
+        data = response.json()
+        assert data['status'] == 'ok'
+        assert data['version'] == '1.0.0'
+        assert 'uptime_seconds' in data
+
+    def test_liveness(self):
+        """Test liveness probe."""
+        response = client.get('/api/v1/health/live')
+        assert response.status_code == 200
+        assert response.json()['alive'] is True
+
+
+class TestModels:
+    def test_list_models(self):
+        """Test listing models."""
+        response = client.get('/api/v1/models')
+        assert response.status_code == 200
+        data = response.json()
+        assert 'available_models' in data
+        assert 'total_models' in data
+        assert 'local_models' in data
+        assert isinstance(data['available_models'], list)
+
+    def test_models_info(self):
+        """Test models directory info."""
+        response = client.get('/api/v1/models-info')
+        assert response.status_code == 200
+        data = response.json()
+        assert 'models_directory' in data
+        assert 'total_size_mb' in data
+        assert 'model_count' in data
+
+
+class TestSystem:
+    def test_system_info(self):
+        """Test system information."""
+        response = client.get('/api/v1/system')
+        assert response.status_code == 200
+        data = response.json()
+        assert data['status'] == 'ok'
+        assert 'cpu_usage_percent' in data
+        assert 'memory_usage_percent' in data
+        assert 'disk_usage_percent' in data
+        assert 'execution_providers' in data
+
+    def test_stats(self):
+        """Test statistics endpoint."""
+        response = client.get('/api/v1/stats')
+        assert response.status_code == 200
+        data = response.json()
+        assert 'total_requests' in data
+        assert 'successful_requests' in data
+        assert 'failed_requests' in data
+
+
+class TestFileManager:
+    def test_ensure_directories(self):
+        """Test directory creation."""
+        with tempfile.TemporaryDirectory() as tmpdir:
+            # Mock settings
+            with patch('app.services.file_manager.settings.upload_dir', f'{tmpdir}/uploads'):
+                with patch('app.services.file_manager.settings.output_dir', f'{tmpdir}/outputs'):
+                    file_manager.ensure_directories()
+                    assert Path(f'{tmpdir}/uploads').exists()
+                    assert Path(f'{tmpdir}/outputs').exists()
+
+    def test_generate_output_path(self):
+        """Test output path generation."""
+        input_path = '/tmp/test.jpg'
+        output_path = file_manager.generate_output_path(input_path)
+        assert output_path.endswith('.jpg')
+        assert 'upscaled' in output_path
+
+    def test_cleanup_directory(self, temp_dir):
+        """Test directory cleanup."""
+        test_dir = temp_dir / 'test_cleanup'
+        test_dir.mkdir()
+        (test_dir / 'file.txt').write_text('test')
+        
+        assert test_dir.exists()
+        file_manager.cleanup_directory(str(test_dir))
+        assert not test_dir.exists()
+
+
+class TestWorker:
+    def test_job_creation(self):
+        """Test job creation."""
+        job = worker.Job(
+            job_id='test-id',
+            status='queued',
+            input_path='/tmp/input.jpg',
+            output_path='/tmp/output.jpg',
+            model='RealESRGAN_x4plus',
+        )
+        
+        assert job.job_id == 'test-id'
+        assert job.status == 'queued'
+        assert 'created_at' in job.to_dict()
+
+    def test_job_metadata_save(self, temp_dir):
+        """Test job metadata persistence."""
+        with patch('app.services.worker.settings.jobs_dir', str(temp_dir)):
+            job = worker.Job(
+                job_id='test-id',
+                status='queued',
+                input_path='/tmp/input.jpg',
+                output_path='/tmp/output.jpg',
+                model='RealESRGAN_x4plus',
+            )
+            
+            job.save_metadata()
+            metadata_file = temp_dir / 'test-id' / 'metadata.json'
+            assert metadata_file.exists()
+            
+            data = json.loads(metadata_file.read_text())
+            assert data['job_id'] == 'test-id'
+            assert data['status'] == 'queued'
+
+
+class TestJobEndpoints:
+    def test_list_jobs(self):
+        """Test listing jobs endpoint."""
+        response = client.get('/api/v1/jobs')
+        assert response.status_code == 200
+        data = response.json()
+        assert 'total' in data
+        assert 'jobs' in data
+        assert 'returned' in data
+
+    def test_job_not_found(self):
+        """Test requesting non-existent job."""
+        response = client.get('/api/v1/jobs/nonexistent-id')
+        assert response.status_code == 404
+
+
+class TestRootEndpoint:
+    def test_root(self):
+        """Test root endpoint."""
+        response = client.get('/')
+        assert response.status_code == 200
+        data = response.json()
+        assert 'name' in data
+        assert 'version' in data
+        assert 'endpoints' in data
+
+
+if __name__ == '__main__':
+    pytest.main([__file__, '-v'])
--- a/tests/test_file_manager.py
+++ b/tests/test_file_manager.py
@@ -0,0 +1,44 @@
+"""Unit tests for file manager."""
+import tempfile
+from pathlib import Path
+from unittest.mock import patch
+
+import pytest
+
+from app.services import file_manager
+
+
+@pytest.fixture
+def temp_data_dir():
+    """Create temporary data directory."""
+    with tempfile.TemporaryDirectory() as tmpdir:
+        yield Path(tmpdir)
+
+
+class TestFileManager:
+    def test_create_request_dir(self, temp_data_dir):
+        """Test request directory creation."""
+        with patch('app.services.file_manager.settings.upload_dir', str(temp_data_dir)):
+            req_dir = file_manager.create_request_dir()
+            assert Path(req_dir).exists()
+            assert Path(req_dir).parent == temp_data_dir
+
+    def test_directory_size(self, temp_data_dir):
+        """Test directory size calculation."""
+        test_file = temp_data_dir / 'test.txt'
+        test_file.write_text('x' * 1024)  # 1KB
+        
+        size_mb = file_manager.get_directory_size_mb(str(temp_data_dir))
+        assert size_mb > 0
+
+    def test_cleanup_old_jobs(self, temp_data_dir):
+        """Test old jobs cleanup."""
+        with patch('app.services.file_manager.settings.jobs_dir', str(temp_data_dir)):
+            # Create old directory
+            old_job = temp_data_dir / 'old-job'
+            old_job.mkdir()
+            (old_job / 'file.txt').write_text('test')
+            
+            # Should be cleaned up with hours=0
+            cleaned = file_manager.cleanup_old_jobs(hours=0)
+            assert cleaned >= 1
				`@@ -0,0 +1 @@`
				`"""Pydantic schemas for request/response validation."""`