image-diet2 documentation¶

Distribute & Pip¶

Installing image-diet2 is simple with pip, just run this in your terminal:

$ pip install image-diet2

or, with easy_install:

$ easy_install image-diet2

But, you really shouldn’t do that.

Get the Code¶

image-diet2 is developed on GitHub, where the code is always available.

You can either clone the public repository:

$ git clone git://github.com/samastur/image-diet2.git

Download the tarball:

$ curl -OL https://github.com/samastur/image-diet2/tarball/master

Or, download the zipball:

$ curl -OL https://github.com/samastur/image-diet2/zipball/master

Once you have a copy of the source, you can embed it in your Python package, or install it into your site-packages easily:

$ python setup.py install

Installing “dependencies”¶

image-diet2 does not have a hard dependency on any external optimisation tool, but it also does not do anything useful without any. You do need to install at least one for each image format you want to handle.

You can find a list of some in pyimagediet’s documentation.

Configuration¶

After you have installed image-diet package and external compression tools, you need to configure it.

First, you need to point image-diet to your configuration file which you do by adding DIET_CONFIG setting to your project’s settings. Its value is the absolute path to the configuration file you want to use.

Configuration is stored in YAML format and is described in pyimagediet’s documentation (image-diet2 uses pyimagediet for actual processing).

An additional value you can set in image-diet2’s configuration file is tmpdir that should point to directory where temporary files will be created. Its default value is /tmp.

If you are using filesystem (Django’s default) as storage and would like to process files with image-diet2 everywhere it is used, then add to settings:

DEFAULT_FILE_STORAGE = 'image_diet.storage.DietStorage'

If you are using some other backend class that you would like to augment with DietStorage, then set DIET_STORAGE setting to that storage class.

Default values¶

image-diet2 already comes with some default values so you do not have to know or type everything. It is enough to provide only changes you want to make and they will either replace previous ones or be added if they are new.

Default configuration file:

# Commands to be executed (label: path)
commands:
  optipng: optipng
  advpng: advpng
  pngcrush: pngcrush
  jpegoptim: jpegoptim
  jpegtran: jpegtran
  gifsicle: gifsicle


# Parameters for commands (label: parameters)
# Use same labels as in command section.
parameters:
  optipng: -force -o7 '{file}'
  advpng: -z4 '{file}s'
  pngcrush: -rem gAMA -rem alla -rem cHRM -rem iCCP -rem sRGB 
            -rem time '{file}' '{output_file}'

  jpegoptim: -f --strip-all '{file}'
  jpegtran: -copy none -progressive -optimize -outfile '{output_file}' '{file}'

  gifsicle: -O2 '{file}' > '{output_file}'


# Pipelines for each file type. Order of labels specifies order of execution
# Use same labels as in command section.
pipelines: {}

# Uncomment and set if you want to backup original image
# backup: orig

# By default pyimagediet returns smallest file it can make even if that is
# the original. If you don't want that (for example to reliably measure 
# effectivness of tools and their parameters) then uncomment next line.
keep_processed: true

# Directory for creating temporary files. Defaults to /tmp when not set.
# tmpdir: /tmp

DietMixin¶

In case your project uses different storage backends or want to use compression only on non-default storage backend then you should use image_diet.storage.DietMixin mixin.

check_diet_tools¶

This command will check system for most common compression tools and print paths of those found in format ready for inclusion in YAML configuration file.

You can also use command line utility diet that comes with pyimagediet which was installed together with image-diet2. You can read about how to use it in pyimagediet’s documentation

diet_images¶

This command will traverse provided list of directories and compress all files with matching pipeline according to image-diet2’s configuration.