Added custom filter support

src/FFMpeg/Filters/Video/CustomFilter.php

@@ -0,0 +1,51 @@
+<?php
+
+/*
+ * This file is part of PHP-FFmpeg.
+ *
+ * (c) Alchemy <dev.team@alchemy.fr>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+namespace FFMpeg\Filters\Video;
+
+use FFMpeg\Format\VideoInterface;
+use FFMpeg\Media\Video;
+
+class CustomFilter implements VideoFilterInterface
+{
+    /** @var string */
+    private $filter;
+    /** @var integer */
+    private $priority;
+
+    /**
+     * A custom filter, useful if you want to build complex filters
+     *
+     * @param string $filter
+     * @param int $priority
+     */
+    public function __construct($filter, $priority = 0)
+    {
+        $this->filter = $filter;
+        $this->priority = $priority;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getPriority()
+    {
+        return $this->priority;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function apply(Video $video, VideoInterface $format)
+    {
+        $commands = array('-vf', $this->filter);
+        return $commands;
+    }
+}

tests/FFMpeg/Tests/Filters/Video/CustomFilterTest.php

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+<?php
+
+namespace FFMpeg\Tests\Filters\Video;
+
+use FFMpeg\Filters\Video\CustomFilter;
+use FFMpeg\Filters\Video\FrameRateFilter;
+use FFMpeg\Tests\TestCase;
+use FFMpeg\Coordinate\FrameRate;
+
+class CustomFilterTest extends TestCase
+{
+    public function testApplyCustomFilter()
+    {
+        $video = $this->getVideoMock();
+        $format = $this->getMock('FFMpeg\Format\VideoInterface');
+
+        $filter = new CustomFilter('whatever i put would end up as a filter');
+        $this->assertEquals(array('-vf', 'whatever i put would end up as a filter'), $filter->apply($video, $format));
+    }
+}