graymap-vmirror!

Synopsis

(graymap-vmirror! graymap)

Parameters

  • grayrmap

Description

This procedure mirrors the graymap destructively and vertically thus exchanging the upper and lower half accordingly.

Side Effects

The graymap is modified.

Return Value

The mirrored graymap is returned.

Example

> (define image (graymap-readpng "example.png"))
image
> (graymap-writepng (graymap-vmirror! image) "example-vmirrored.png")
ok
>