Add crop filter implementation

Imagine/Filter/Loader/CropFilterLoader.php

@@ -0,0 +1,20 @@
+<?php
+
+namespace Avalanche\Bundle\ImagineBundle\Imagine\Filter\Loader;
+
+use Imagine\Image\Box;
+use Imagine\Image\Point;
+
+use Imagine\Filter\Basic\Crop;
+use Imagine\Image\ImageInterface;
+
+class CropFilterLoader implements LoaderInterface
+{
+    public function load(array $options = array())
+    {
+        list($x, $y) = $options['start'];
+        list($width, $height) = $options['size'];
+
+        return new Crop(new Point($x, $y), new Box($width, $height));
+    }
+}

README.md

@@ -313,6 +313,18 @@ avalanche_imagine:
 
 ```
 
+### Crop
+
+The `crop` filter crop an image with start coordinate, and size dimension.
+
+``` yaml
+avalanche_imagine:
+    filters:
+        crop:
+            type   : crop
+            options: { start: [0, 0], size: [100, 100] } #crop image with 100x100 square box
+```
+
 ## Load your Custom Filters
 
 The ImagineBundle allows you to load your own custom filter classes. The only
@@ -369,4 +381,4 @@ $avalancheService = $this->get('imagine.cache.path.resolver');
 Then, call the getBrowserPath and pass the original image webpath and the filter you want to use
 ```php
 $cachedImage = $avalancheService->getBrowserPath($object->getWebPath(), 'my_thumb');
-```
+```

Resources/config/imagine.xml

@@ -49,6 +49,8 @@
 
         <parameter key="imagine.filter.loader.chain.class">Avalanche\Bundle\ImagineBundle\Imagine\Filter\Loader\ChainFilterLoader</parameter>
 
+        <parameter key="imagine.filter.loader.crop.class">Avalanche\Bundle\ImagineBundle\Imagine\Filter\Loader\CropFilterLoader</parameter> 
+
     </parameters>
 
     <services>
@@ -135,6 +137,10 @@
             <argument type="service" id="imagine.filter.manager" />
             <tag name="imagine.filter.loader" filter="chain" />
         </service>
+
+        <service id="imagine.filter.loader.crop" class="%imagine.filter.loader.crop.class%">
+            <tag name="imagine.filter.loader" filter="crop" />
+        </service>
 
     </services>
 </container>