N4veen4/HueNova — reverse-engineered prompt

Build me a beginner friendly image colorization web app where someone can upload a black and white photo and get back a realistic colorized version.

Use Python for the backend and make it run locally in the browser. The app should use a pre trained CNN colorization model with OpenCV, working from the grayscale lightness channel and predicting the color channels. Please include a clean polished interface with upload, preview, colorize button, loading state, and a before and after result view.

Make sure the app checks that the needed model files exist in a models folder and gives a helpful message if they’re missing. It should handle normal image formats, resize large images if needed, and return the final colorized image for viewing or downloading.

Please include simple setup instructions, a requirements file, and make it easy to run with python main.py and open localhost in the browser. If you need exact model file links or OpenCV details, look up the current docs online.