| django-image-diet |
|---|
|
|
| django-image-diet is a Django application for removing unnecessary bytes from image |
| files. It optimizes images without changing their look or visual quality |
("losslessly") and it also has the ability to decrease color depth of png, which is usually not noticeable to human eye. |
| It works on images in JPEG, GIF and PNG formats and will leave others |
| unchanged. Provides a seemless integration with easy-thumbnails app, but can |
work with others too. |
| Original image-diet app was written and is being maintained by Marko Samastur (markos@gaivo.net) |
and is licensed under MIT license. |
| Installation |
| ============ |
Add |
|
|
|
|
Check which tools are already installed by executing: |
|
| Install those reported missing or disable them as described by command's |
output (or Usage section). requirements.txt lists all tools together |
with their home addresses and tips for installation. |
| If you are using recent version of easy-thumbnails, then you're done. |
| 'django-image-diet' will automatically squeeze unnecessary bytes every time |
a thumbnail is created. |
If you aren't, then read further. |
| Usage |
| ===== |
django-image-diet is used to remove unnecessary bytes from images. This means |
| every byte that will not change final display of the image including meta |
| information stored in EXIF etc. DO NOT use this app if this is not |
acceptable or if your image storage is not a local file system. |
| Primary motivation for its development was seemless optimization of images |
created by easy-thumbnails. PIL is in many ways a great library, but its |
output tends to be verbose. |
If you are using a recent version of easy-thumbnails, then you shouldn't |
need to do anything more than described in Installation. It is important |
| to disable tools that are not available since app for efficiency reasons |
doesn't check during runtime. |
You may use manage.py check_diet_tools action any time to check current |
| status of external utilities. Action also provides copy&paste ready list of |
configuration options for disabling those that could not be found. |
You may still be able to use django-image-diet even if you are not using |
easy-thumbnails. Installation procedure is the same, but you will need |
| to trigger shrinking from your code (or let me know which public app you are |
using so I can add support for it). |
To do this import: |
|
And call squeeze(path_to_image) where path_to_image is an absolute |
path to image you want to optimize. Function returns None if there was a |
problem or path to squeezed image if it was successful. |
| Returned path is currently always the same as the one provided, but this may |
change in the future (when GIF to PNG8 transformation gets added). |
If you installed image-diet after you already processed some images, then |
you can shrink them with manage.py diet_images command. Just pass paths |
| to directories you want to scan for images as command's argumentand it will |
| process all images that can be found in those directories or their |
subdirectories. |
| Available management commands |
| ----------------------------- |
| - compress_remote_images |
| - diet_images |
|
| Configuration options |
| --------------------- |
DIET_DEBUG = True |
| ~~~~~~~~~~~~~~~~~~~~~ |
| This will keep uncompressed versions of images on disk with |
an extension |
DIET_<TOOLNAME> = False |
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~ |
Disable use of TOOLNAME. Name has to be written in uppercase so |
|
DIET_PNGQUANT_BRUTE = False |
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ |
| False by default. Enables full lossy compression of pngquant. Otherwise |
pngquant compression quality is restricted to 90-100 - almost loosless. |
| TODO/Wishlist |
| ============= |
| - remove deprecated optparse - replace with argparse |
| - stop depending on tools that processed image will actually be smaller |
|
| Known bugs |
| ========== |
| - app doesn't check if files exist so some operations could lead |
|
| External tools used for image shrinking. |
JPEG: - jpegtran (http://jpegclub.org/jpegtran/; included in libjpeg-progs package on Ubuntu) - Jpegoptim (http://www.kokkonen.net/tjko/projects.html)
GIF (used only for optimizing animated GIFs): - Gifsicle (http://www.lcdf.org/gifsicle/)
PNG: - OptiPNG (http://optipng.sourceforge.net/) - AdvanceCOMP PNG (http://advancemame.sourceforge.net/doc-advpng.html) - Pngcrush (http://pmt.sourceforge.net/pngcrush/) - PngQuant
Ubuntu packages are: - libjpeg-progs - jpegoptim - gifsicle - optipng - advancecomp - pngcrush - pngquant
CentOS packages are: - jpegtran: libjpeg - jpegoptim: can't find rpm on internet - gifsicle: gifsicle package on repoforge - optipng: optipng package in EPEL - advancecomp: advancecomp package on repoforge - pngcrush: pngcrush package on repoforge - pngquant: TODO update instructions
Brew for MacOSX: - jpeg - jpegoptim - gifsicle - optipng - advancecomp - pngcrush - pngquant
Alternative on MacOSX: Install imageoptim (http://imageoptim.com) and then symlink from /usr/bin/ to all the required packages: sudo ln -s /Applications/ImageOptim.app/Contents/MacOS/advpng sudo ln -s /Applications/ImageOptim.app/Contents/MacOS/gifsicle sudo ln -s /Applications/ImageOptim.app/Contents/MacOS/jpegoptim sudo ln -s /Applications/ImageOptim.app/Contents/MacOS/jpegtran sudo ln -s /Applications/ImageOptim.app/Contents/MacOS/optipng sudo ln -s /Applications/ImageOptim.app/Contents/MacOS/pngcrush pngquant: TODO update instructions