Convert and resize images using the command line

ImageMagick is a set of tools that can be used to read, write, and manipulate images in almost any format including TIFF, JPEG, PNG, PDF, PhotoCD, and GIF.

The advantage of ImageMagick is that it can be used to create images dynamically making it suitable for Web apps. In addition, you can resize, rotate, sharpen, color reduce and add special effects to an image. However, ImageMagick is strictly for those familiar with the command line as there is no GUI. You can only make changes to images using commands such as “$magick> convert rose.jpg rose.png”.

For those familiar with programming languages, you can use C, C++, Perl, Java, PHP, Python, or Ruby to make changes. A high-quality 2D renderer is also included which provides SVG capabilities. If you are familiar with programming commands, then the range of actions possible with ImageMagick is truly impressive including, conversions, resizing, transparencies, animated GIFs and shape drawing. However, the lack of GUI will exclude most people from using it.

If you’re familiar with programming languages and need a powerful command line based tool, Image Magick is worth exploring.

ImageMagick is a free software suite to create, edit, and compose bitmap images. It can read, convert and write images in a large variety of formats. Images can be cropped, colors can be changed, various effects can be applied, images can be rotated and combined, and text, lines, polygons, ellipses and Bézier curves can be added to images and stretched and rotated.

Most of the functionality of ImageMagick can be used interactively from the command line; more often, however, the features are used from programs written in the programming languages C, Ch, C++, Java, Perl, PHP, Python, Ruby, Tcl/Tk, for which ready-made ImageMagick interfaces (PerlMagick, Magick++, PythonMagick, MagickWand for PHP, RMagick, TclMagick, and JMagick) are available. This makes it possible to modify or create images automatically and dynamically.