how to apply grayscale filter on an image?

Question

Could you please tell how to apply a grayscale filter on an image with LiipImagineBundle?

NB: I am using Symfony2

Thank,

Answer 1

This worked for me:

<?php

namespace AppBundle\Imagine\Filter\Loader;

use Imagine\Filter\Advanced\Grayscale;
use Imagine\Image\ImageInterface;
use Liip\ImagineBundle\Imagine\Filter\Loader\LoaderInterface;

/**
 * Apply a grayscale effect to image.
 */
class GrayscaleFilterLoader implements LoaderInterface
{
    /**
     * {@inheritdoc}
     */
    public function load(ImageInterface $image, array $options = [])
    {
        $filter = new Grayscale();

        return $filter->apply($image);
    }
}

Just define a service like this one:

services:
    liip_imagine.filter.loader.grayscale:
        class: AppBundle\Imagine\Filter\Loader\GrayscaleFilterLoader
        tags:
            - { name: liip_imagine.filter.loader, loader: grayscale}

And then a filter:

liip_imagine:
    filter_sets:
        grayscale:
            filters:
                grayscale: ~

Answer 2

There is no built-in grayscale filter in LiipImagineBundle, so you could create a custom filter loader by 3 steps:

1) At first, you should create GrayscaleFilterLoader class, it should implement the Liip\ImagineBundle\Imagine\Filter\Loader\LoaderInterface as like as any other custom filter:

namespace AppBundle\Imagine\Filter\Loader;

...

/**
 * Class GrayscaleFilterLoader
 * @package AppBundle\Imagine\Filter\Loader
 */
class GrayscaleFilterLoader implements LoaderInterface
{
    /**
     * @param ImageInterface $image
     * @param array $options
     * @return ImageInterface
     */
    public function load(ImageInterface $image, array $options = [])
    {
        $image->effects()->grayscale();

        return $image;
    }
}

2) Then, you should register it in the service container and add the liip_imagine.filter.loader tag to it, the loader tag would be the name of the filter:

#app/config/services.yml
liip_imagine.filter.loader.grayscale:
    class: AppBundle\Imagine\Filter\Loader\GrayscaleFilterLoader
    tags:
        - { name: liip_imagine.filter.loader, loader: grayscale}

3) Finally, configure the filter set with it:

#app/config/config.yml
your_filter_set_name:
    filters:
        ...
        grayscale: {}

That's it!