5l1v3r1 / imagemanip

An OS X command-line utility for manipulating image files in batch.

imagemanip

The purpose of imagemanip is to provide an easy-to-use batch image modification service. In simpler terms, you can use it to do the same thing to a whole lot of images at once.

Usage

The imagemanip command takes three initial arguments: command, input, and output. The command specifies what you would like to do to each image. The input should be a file path to either a single image file, or to a directory of images. When the command is applied to a file indicated by input, the result is written to output in one of two ways: if input was a directory, output will be created as a directory containing the resultant images; if input was a file, output will be a file with the resultant image.

The scale command

Resizing images in batch can sometimes be necessary for an app or web developer. The scale command allows you to specify either relative or absolute dimensions. To scale images absolutely, use the px suffix:

imagemanip scale input/ output/ --width 100px --height 150px
imagemanip scale input/ output/ --both 100px

To scale images relative to their existing size, use the % suffix:

imagemanip scale input/ output/ --width 100% --height 150%

The color command

It is common to use an image mask to represent a particular shape. The color command makes it easy to take image masks like this and change their color. Under the hood, the command simply preserves the transparency of each pixel while changing its color.

There are two ways to specify color to color. My personal preference is to use rgba(red,green,blue,alpha), where red, green, and blue are integers from 0 to 255 and alpha is a float from 0 to 1. The other option is to use an HTML-style hex color code.

imagemanip color input/ output/ \#FF0000
imagemanip color input/ output/ rgba\(128,128,0,1\)

Creating New Commands

You can implement your own commands with ease! Just subclass the IMTransformation class and implement the following methods:

// initialize or throw an exception if you don't like the args
- (id)initWithImage:(ANImageBitmapRep *)image
          arguments:(NSArray *)args;

// perform your operation on self.image or throw an exception
- (void)perform;

+ (NSString *)commandName; // pretty straightforward
+ (NSString *)summary; // description for help screen
+ (NSString *)fullUsage; // for `imagemanip help commandName`

Then, in main.m, import YourClass.h and add [YourClass class] to the classes array.