bitmap->greymap

Synopsis

(bitmap->greymap bitmap)

Parameters

  • bitmap

Description

The supplied bitmap is comverted to a new greymap. Every 1 in the originating bitmap results in a grey value of 0 (black), every 0 results in a grey value of 255 (white).

Side Effects

Return Value

The resulting greymap is returned.

Example

> (define bitmap (bitmap-create 640 480))
bitmap
> (bitmap-equal? bitmap (greymap->bitmap (bitmap->greymap bitmap)))
#t
>