magick-rust

A somewhat safe Rust interface to the ImageMagick system, in particular, the MagickWand library. Many of the functions in the MagickWand API are still missing, and those that are needed will be gradually added.

Dependencies

• Rust (~latest release)
• Cargo (~latest release)
• ImageMagick (version 7.0)
  • FreeBSD provides this version
  • Homebrew requires special steps:
    • brew install imagemagick
  • Linux may require building ImageMagick from source
• Clang (version 3.5 or higher)
  • Or whatever version is dictated by rust-bindgen
• Must have pkg-config in order to link with MagickWand.

Build and Test

Pretty simple for now.

$ cargo build
$ cargo test

Example Usage

MagickWand has some global state that needs to be initialized prior to using the library, but fortunately Rust makes handling this pretty easy. In the example below, we read in an image from a file and resize it to fit a square of 240 by 240 pixels, then convert the image to JPEG.

use magick_rust::{MagickWand, magick_wand_genesis};
use std::sync::{Once, ONCE_INIT};

// Used to make sure MagickWand is initialized exactly once. Note that we
// do not bother shutting down, we simply exit when we're done.
static START: Once = ONCE_INIT;

fn resize() -> Result<Vec<u8>, &'static str> {
    START.call_once(|| {
        magick_wand_genesis();
    });
    let wand = MagickWand::new();
    try!(wand.read_image("kittens.jpg"));
    wand.fit(240, 240);
    wand.write_image_blob("jpeg")
}

Writing the image to a file rather than an in-memory blob is done by replacing the call to write_image_blob() with write_image(), which takes a string for the path to the file.

Docker

Docker can be used to build and test the code without affecting your development environment, which may have a different version of ImageMagick installed. The use of docker-compose, as shown in the example below, is optional, but it makes the process very simple.

$ cd docker
$ docker-compose build
$ docker-compose start
$ docker-compose run magick-rust
$ cargo build
$ cargo test