AIU — AI Image Upscaler

Upscale low-quality images using Real-ESRGAN and auto-fit them to any device screen.

Setup

python -m venv venv
venv\Scripts\activate          # Windows
pip install -r requirements.txt

The Real-ESRGAN binary (realesrgan-ncnn-vulkan) is downloaded automatically on first run.

Test (Python only)

python test_upscale.py --image tests/test.png
python test_upscale.py --image tests/test.png --device iphone_15_pro --fit cover
python test_upscale.py --scale 2
python test_upscale.py --list-devices

Run the web app

python run_server.py

Open http://localhost:8000

API

Method	Endpoint	Description
GET	/api/health	Health check
GET	/api/devices	List device presets
POST	/api/upscale	Upscale an image
POST	/api/upscale-device	Upscale + fit to device screen

POST /api/upscale

Field	Type	Default	Notes
file	file	—	Image upload
scale	int	4	2 or 4
output_format	str	PNG	PNG/JPEG/WEBP

POST /api/upscale-device

Same as above, plus:

Field	Type	Default	Notes
device	str	—	Preset key (e.g. iphone_15_pro)
screen_width	int	—	Custom width (CSS px)
screen_height	int	—	Custom height (CSS px)
dpr	float	1.0	Device pixel ratio
fit	str	contain	contain / cover / fill

Device resolution priority: preset > custom dims > User-Agent > desktop_1080p fallback.

Device Presets

Phones: iPhone 15 Pro, iPhone 14, iPhone SE, Pixel 8, Galaxy S24 Tablets: iPad Pro 12.9", iPad Air Desktop: 1080p, 1440p, 4K, MacBook Pro 14", MacBook Air 13"

Stack

• Real-ESRGAN (ncnn-vulkan) — GPU-accelerated image super-resolution
• FastAPI — REST API
• Pillow — Image processing
• Vanilla JS — Frontend