filters.md

Filters

Built-in Filters

The thumbnail filter

The thumbnail filter, as the name implies, performs a thumbnail transformation on your image.

The mode can be either outbound or inset. Option inset does a relative resize, where the height and the width will not exceed the values in the configuration. Option outbound does a relative resize, but the image gets cropped if width and height are not the same.

Given an input image sized 50x40 (width x height), consider the following annotated configuration examples:

liip_imagine:
    filter_sets:
        my_thumb_out:
            filters:
                thumbnail: { size: [32, 32], mode: outbound } # Transforms 50x40 to 32x32, while cropping the width
        my_thumb_in:
            filters:
                thumbnail: { size: [32, 32], mode: inset } # Transforms 50x40 to 32x26, no cropping

There is also an option allow_upscale (default: false). By setting allow_upscale to true, an image which is smaller than 32x32px in the example above will be expanded to the requested size by interpolation of its content. Without this option, a smaller image will be left as it. This means you may get images that are smaller than the specified dimensions.

The relative_resize filter

The relative_resize filter may be used to heighten, widen, increase or scale an image with respect to its existing dimensions. These options directly correspond to methods on Imagine's BoxInterface.

Given an input image sized 50x40 (width, height), consider the following annotated configuration examples:

liip_imagine:
    filter_sets:
        my_heighten:
            filters:
                relative_resize: { heighten: 60 } # Transforms 50x40 to 75x60
        my_widen:
            filters:
                relative_resize: { widen: 32 }    # Transforms 50x40 to 32x26
        my_increase:
            filters:
                relative_resize: { increase: 10 } # Transforms 50x40 to 60x50
        my_widen:
            filters:
                relative_resize: { scale: 2.5 }   # Transforms 50x40 to 125x100

The upscale filter

The upscale filter, as the name implies, performs a upscale transformation on your image. Configuration looks like this:

liip_imagine:
    filter_sets:
        my_thumb:
            filters:
                upscale: { min: [800, 600] }

The crop filter

The crop filter, as the name implies, performs a crop transformation on your image. Configuration looks like this:

liip_imagine:
    filter_sets:
        my_thumb:
            filters:
                crop: { start: [10, 20], size: [120, 90] }

The strip filter

The strip filter removes all profiles and comments from your image. Configuration looks like this:

liip_imagine:
    filter_sets:
        my_thumb:
            filters:
                strip: ~

The background filter

The background filter sets a background color for your image, default is white (#FFF). Configuration looks like this:

liip_imagine:
    filter_sets:
        my_thumb:
            filters:
                background: { color: '#00FFFF' }

If you provide a size it will create a new image (this size and given color), and apply the original image on top:

liip_imagine:
    filter_sets:
        my_thumb:
            filters:
                background: { size: [1026, 684], color: '#fff' }

The watermark filter

The watermark filter pastes a second image onto your image while keeping its ratio. Configuration looks like this:

liip_image:
    filter_sets:
        my_image:
            filters:
                watermark:
                    # Relative path to the watermark file (prepended with "%kernel.root_dir%/")
                    image: Resources/data/watermark.png
                    # Size of the watermark relative to the origin images size
                    size: 0.5
                    # Position: One of topleft,top,topright,left,center,right,bottomleft,bottom,bottomright
                    position: center

Please note that position of watermark filter is important. If you have some filters like crop after it is possible that watermark image will be cropped.

The auto_rotate filter

The auto_rotate filter rotates the image based on its EXIF data. (this filter should be called as early as possible) Configuration looks like this:

liip_imagine:
    filter_sets:
        my_thumb:
            filters:
                auto_rotate: ~

Load your Custom Filters

The ImagineBundle allows you to load your own custom filter classes. The only requirement is that each filter loader implement the following interface:

Liip\ImagineBundle\Imagine\Filter\Loader\LoaderInterface

To tell the bundle about your new filter loader, register it in the service container and apply the liip_imagine.filter.loader tag to it (example here in XML):

<service id="liip_imagine.filter.loader.my_custom_filter" class="Acme\ImagineBundle\Imagine\Filter\Loader\MyCustomFilterLoader">
    <tag name="liip_imagine.filter.loader" loader="my_custom_filter" />
</service>

For more information on the service container, see the Symfony2 Service Container documentation.

You can now reference and use your custom filter when defining filter sets you'd like to apply in your configuration:

liip_imagine:
    filter_sets:
        my_special_style:
            filters:
                my_custom_filter: { }

For an example of a filter loader implementation, refer to Liip\ImagineBundle\Imagine\Filter\Loader\ThumbnailFilterLoader.

Dynamic filters

With a custom controller action it is possible to dynamically modify the configuration that will be applied to the image. Inside the controller you can access FilterManager instance, pass configuration as third parameter of applyFilter method (for example based on information associated with the image or whatever other logic you might want).

A simple example showing how to change the filter configuration dynamically.

public function filterAction($path, $filter)
{
    if (!$this->cacheManager->isStored($path, $filter)) {
        $binary = $this->dataManager->find($filter, $path);

        $filteredBinary = $this->filterManager->applyFilter($binary, $filter, array(
            'filters' => array(
                'thumbnail' => array(
                    'size' => array(300, 100)
                )
            )
        ));

        $this->cacheManager->store($filteredBinary, $path, $filter);
    }

    return new RedirectResponse($this->cacheManager->resolve($path, $filter), 301);
}

Back to the index