Simple, efficient *Magick rubygem

Features

MicroMagick lets you use ImageMagick or GraphicsMagick from ruby.

Using MicroMagick:

• doesn't bloat your ruby process when you process large images (like rmagick)
• supports valid geometry specifications, like 640x480> (which doesn't work with mini_magick and quick_magick)
• doesn't create unnecessary tempfiles (like mini_magick)
• doesn't assume you only needed to resize your images (like imagery)
• supports identification of corrupt images (which is unique to MicroMagick). (Note that this support wasn't added to ImageMagick until version 6.7.0, but has been present in GraphicsMagick for several years).

MicroMagick has excellent test coverage and code quality.

Usage

img = MicroMagick::Image.new("/path/to/image.jpg")
img.strip.quality(85).resize("640x480>").write("640x480.jpg") unless img.corrupt?

This will

1. Read /path/to/image.jpg

2. Verify the image is not corrupt, using identify

3. Set up a convert command to

   • remove EXIF headers (strip),
   • use 85% JPEG quality,
   • resize to 640x480 only if the source image is bigger than those dimensions (hence the '>' suffix)
   • write the results to '640x480.jpg'

This results in the following system call:

gm convert -size 640x480 /path/to/image.jpg +profile \* -quality 85 -resize "640x480>" /new/path/image-640x480.jpg

To get image dimensions:

img.width
# => 3264
img.height
# => 2448

What about EXIF information?

To access EXIF metadata information, including properly typed values, see the exiftool and exiftool_vendored gems.

Installation

Add gem 'micro_magick' to your Gemfile and run bundle.

You'll also need to install GraphicsMagick.

If you're on a Mac with homebrew, brew install graphicsmagick.

"Plus" options

To add an output option that has a "plus" prefix, like, +matte, use .add_output_option("+matte").

Goodies

There are a couple additional methods that have been added to address common image tasks:

• img.strip removes all comments and EXIF headers
• img.square_crop crops the image to a square (so a 640x480 image would crop down to a 480x480 image, cropped in the middle).

Note that micro_magick delegates all parameter validation to the underlying library. A MicroMagick::ArgumentError will be raised on .write or .overwrite if ImageMagick or GraphicsMagick writes anything to stderr.

GraphicsMagick versus ImageMagick

At least in my testing, GraphicsMagick blows ImageMagick out of the water.

In resizing a 2248x4000 image to 640x480:

• GraphicsMagick takes ~140 milliseconds. ImageMagick takes ~550 millis.
• GraphicsMagick outputs a 37K JPG, ImageMagick outputs a 94K JPG, with no detectable visual differences.

Not only is GraphicsMagick 4 times faster, it produces 2.5x smaller output with the same quality--WIN WIN.

Because of this, if you have GraphicsMagick installed, MicroMagick will use it by default. You can force which library to use with the MicroMagick.use_graphicsmagick! and MicroMagick.use_imagemagick! methods.

To see which external library and version you're using:

MicroMagick.version
=> #<Gem::Version "1.3.21">
MicroMagick.imagemagick?
=> false
MicroMagick.graphicsmagick?
=> true

Changelog

1.1.0

• Allow supplying input file options. Thanks, whitequark!

1.0.1

Added explicit MIT licensing.

1.0.0

Please note that the attributes hash associated to images has been removed in this version, in the interests of correctness. If you need EXIF metadata, use the exiftool gem.

• Updated identity parsing to only dimensions. Addresses Issue 3 (multi-value), and Issue 5 (NULL bytestreams)
• Updated Travis configuration

0.0.7

• There's only one common Image class now
• Added identify -verbose parsing
• Added support for mogrify with new .overwrite method

0.0.6

Cleaned up some packaging/mode bit issues

0.0.5

Fixed gemspec metadata

0.0.4

Input file -size render hint is now only used with simple dimension specifications

0.0.3

Added square_crop, image dimensions, and support for +options.

0.0.1

Let's get this party started.