Photo Studio is a browser tool for grading, graining and glitching a photo, with presets to start from and a full-resolution download.
One WebGL fragment shader draws both the live preview and the final export, so what you see matches the file you get. The controls change the colour grade, add film-style grain and apply glitch distortion. Large photos are capped to a size your device can handle, and the app says so when that happens.
It involves no model at all, just image maths on your own machine.