- Created by Dominika Kurek, last modified by André Rømcke on Jan 23, 2017
Introduction
Image variations (image aliases) allow you to define and use different versions of the same image. You generate variations based on filters which modify aspects such as size and proportions, quality or decorations.
Image variations are generated with LiipImagineBundle, using the underlying Imagine library from avalanche123. This bundle supports GD, Imagick or Gmagick PHP extensions, and allows you to define flexible filters in PHP. Image files are stored using the IOService,
and are completely independent from the ezimage
Field Type. They are generated only once and cleared on demand (e.g. on content removal).
Configuration
Custom image variations are defined in ezplatform.yml
or any imported semantic configuration file. The definition is dynamic, so it can be configured per siteaccess and all the other scopes.
Important
_
or -
or numbers, but no spaces.The following parameters are set for each variation:
reference
: Name of a reference variation to base the variation on. If set tonull
(or~
, which meansnull
in YAML), the variation will take the original image for reference. It can be any available variation configured in theezpublish
namespace, or afilter_set
defined in theliip_imagine
namespace.filters
: Array of filter definitions (hashes containingname
andparams
keys). See possible values below.
Default image variations
A few basic image variations are included by default in eZ Platform in the default_settings.yml
config file:
Usage
Filter usage examples
Scaling with an eZ Platform filter
This configuration defines a medium
image variation that is scaled to a width of 700 px.
Image quality with a liip filter
This configuration adds a limit to the image quality using a liip filter.
You can use both an eZ Platform and a liip filter for the same image variation, in this case medium
.
Notice that the liip_imagine
key is not placed under image_variations
, but at the same level as ezpublish
.
Post-Processors
LiipImagineBundle supports post-processors on image aliases. It is possible to specify them in image variation configuration:
Please refer to post-processors documentation in LiipImagineBundle for details.
Drivers
LiipImagineBundle supports GD (default), Imagick and GMagick PHP extensions and only works on image blobs (no command line tool is needed). See the bundle's documentation to learn more on that topic.
Upgrade
Instantiate LiipImagineBundle
in your kernel class
If you were using ImageMagick, install Imagick or Gmagick PHP extensions and activate the driver in liip_imagine
(see LiipImagineBundle configuration documentation for more information):
GD will be used by default if no driver is specified.
Purging aliases
It is possible to use the Liip Imagine console tool to clear generated aliases.
The first example will clear the image files for the large
alias. The second will clear all the generated aliases (be careful), and list the removed files (-v).
The naming scheme change introduced by this feature wasn't enabled by default on 5.4.x. As part of migration you'll need to adapt to the new schema to get the benefit of this more efficient purge method. More technical information can be found on the pull request.
Reference
Available filters
In addition to filters exposed by LiipImagineBundle, the following are available:
Filter name | Parameters | Description |
---|---|---|
geometry/scaledownonly | [width, height] | Generates a thumbnail that will not exceed width/height. |
geometry/scalewidthdownonly | [width] | Generates a thumbnail that will not exceed width. |
geometry/scaleheightdownonly | [height] | Generates a thumbnail that will not exceed height. |
geometry/scalewidth | [width] | Alters image width. Proportion will be kept. |
geometry/scaleheight | [height] | Alters image height. Proportion will be kept. |
geometry/scale | [width, height] | Alters image size, not exceeding provided width and height. Proportion will be kept. |
geometry/scaleexact | [width, height] | Alters image size to fit exactly provided width and height. Proportion will not be kept. |
geometry/scalepercent | [widthPercent, heightPercent] | Scales width and height with provided percent values. Proportion will not be kept. |
geometry/crop | [width, height, startX, startY] | Crops the image. Result will have provided width/height, starting at provided startX/startY |
border | [thickBorderX, thickBorderY, color=#000] | Adds a border around the image. Thickness is defined in px. Color is "#000" by default. |
filter/noise | [radius=0] | Smooths the contours of an image (imagick /gmagick only). radius is in pixel. |
filter/swirl | [degrees=60] | Swirls the pixels of the center of an image (imagick /gmagick only). degrees defaults to 60°. |
resize | {size: [width, height]} | Simple resize filter (provided by LiipImagineBundle). |
colorspace/gray | N/A | Converts an image to grayscale. |
LiipImagineBundle supports additional settings, it is possible to combine filters from the list above to the ones provided in LiipImagineBundle or custom ones.
Discarded filters
The following filters exist in the Imagine library but are not used in eZ Platform due to incompatibility:
flatten
. Obsolete, images are automatically flattened.bordercolor
border/width
colorspace/transparent
colorspace
Custom filters
Please refer to LiipImagineBundle documentation on custom filters. Imagine library documentation may also be useful.