Common Lisp bindings to ImageMagick's
MagicWand API.
This is a fork of LISP-MAGICK.
It is compatible with recent versions of ImageMagick (7.x)
and has a slightly different API.
For the most part, you can use the C API as a reference. Translations follow a few simple rules:
- Function names are lisp-ified. For example,
MagickGetImageWidthbecomesmagick:get-image-width. Note that we omit any redundantMagickprefix. - Functions that return multiple results via pointer arguments return multiple values.
- In most cases, a failed operation is signaled as
magick-wand-errorcondition. - When a function expects an array of values and its length, a vector
or a list can be passed in CL-MAGICK, and the length parameter is
omitted.
nilis passed as aNULLpointer (but#()is not).
(defpackage :lisp-magick-examples
(:use :cl))
(in-package :lisp-magick-examples)
(defun create-thumbnail (filename thumbname width height)
"Create a thumbnail the image in FILENAME with a max size of WIDTH x HEIGHT
pixel (but with the original aspect ratio) and save it in THUMBNAME."
(magick:with-magick-wand (wand :load filename)
(let ((a (/ (magick:get-image-width wand)
(magick:get-image-height wand))))
(if (> a (/ width height))
(magick:scale-image wand width (truncate (/ width a)))
(magick:scale-image wand (truncate (* a height)) height)))
(magick:write-image wand thumbname)))
(defun draw-a-few-lines (filename width height)
"Create a new image with WIDTH x HEIGHT pixel containing 50 random lines
and save it in FILENAME."
(magick:with-magick-wand (wand :create width height :comp (0 0 0))
(magick:with-drawing-wand (dw)
(magick:with-pixel-wand (pw :comp (255 255 255))
(magick:draw-set-stroke-color dw pw))
(magick:draw-set-stroke-width dw 3d0)
(dotimes (i 50)
(magick:draw-line dw
(coerce (random width) 'double-float)
(coerce (random height) 'double-float)
(coerce (random width) 'double-float)
(coerce (random height) 'double-float)))
(magick:draw-image wand dw))
(magick:write-image wand filename)))