| Requirement | Value |
|---|---|
| Shadow removal | Adjustable |
| Ink darkening | Adjustable |
| Sizes | 256x64, 128x55, 413x177, custom |
A signature photographed on paper carries the paper with it. The background comes out grey rather than white, the hand casts a shadow across one corner, and thin strokes that were clear on paper turn faint once the file is compressed. Portals reject the result, or the verifying officer cannot read it.
One curve fixes all three. The tool works out what this particular photograph calls white — not the brightest pixel, which is usually a glare spot, but the level the paper actually sits at — then pushes everything at or above it to pure white and bends what is below toward black.
Two sliders control it. Raise the first until the background goes clean white; push it too far and thin strokes vanish, so stop as soon as the paper is clear. The second darkens the ink itself, which is what rescues a signature made with a light pen.
The cleaning runs at the original resolution and the picture is fitted afterwards. Cleaning a shrunken signature loses the thin strokes before the curve ever sees them.
A cleaned signature compresses very easily and often drops under the minimum size a portal expects — Aaple Sarkar refuses anything under 5 KB. The floor is respected here, not just the ceiling.