Module filter 

Convolution filter operations (blur, sharpen, edge detection)

Structs

FilterOperation

Convolution filter operations

Functions

bilateral_filter

CPU bilateral filter: edge-preserving spatial filter.

box_blur

CPU box blur: separable two-pass sliding-sum, O(w×h) per channel.

gaussian_blur_separable

CPU-side separable Gaussian blur (two-pass: horizontal then vertical).

gaussian_blur_separable_parallel

CPU-side separable Gaussian blur with Rayon parallel row/column processing.

gaussian_kernel_1d

Build a normalised 1-D Gaussian kernel of radius ceil(3σ).

max_channel_diff

Compare two RGBA u8 buffers and return the maximum absolute channel difference.

median_filter

CPU median filter: sorts a (2r+1)×(2r+1) neighbourhood per pixel/channel.