Color Emboss Image

The fixed kernel below processes red, green and blue separately. It repeats the nearest pixel beyond each edge, clips channel values to 0–255 and retains alpha. Colors can change; this produces colored relief, not unchanged original colors. In the grayscale example below, the center becomes 28 in every RGB channel, a dark tone.

[-2,-1,0; -1,1,1; 0,1,2]

3×3: [0,1,2; 3,4,5; 6,7,8]
→ [12,16,14; 24,28,26; 18,22,20]

One image, at most 25 MiB and 24,000,000 decoded pixels. Output keeps the decoded dimensions and uses the source basename plus -colorEmboss.png. Browser canvas processing may round RGB values at partial transparency and omit EXIF or color-profile metadata. Animation is not preserved; the decoded frame is exported. The fixed effect may amplify noise and lose detail through clipping. Keep the original. This is local image processing, not 3D reconstruction or adjustable lighting.