Bilateral Noise Reduction

A bilateral filter weights neighbouring pixels by both spatial distance and luminance similarity, so flat regions get smoothed heavily while edges are left almost untouched. That edge preservation is the entire point of choosing it over a plain Gaussian blur.

The limits, stated plainly: bilateral filtering handles light luminance noise well, but it is clearly weaker than non-local means or a dedicated denoiser on high-ISO chroma noise and structured pattern noise. Its cost is O(r²) per pixel, so larger radii slow down noticeably on high-resolution files. It is not claimed to replace a professional denoiser, and a heavier method will be worth adding once WebGPU compute is a safe assumption across browsers.