Added watermark functionality and unit tests

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

@@ -0,0 +1,63 @@
+<?php
+
+namespace FFMpeg\Tests\Filters\Video;
+
+use FFMpeg\FFProbe\DataMapping\Stream;
+use FFMpeg\FFProbe\DataMapping\StreamCollection;
+use FFMpeg\Filters\Video\RotateFilter;
+use FFMpeg\Filters\Video\WatermarkFilter;
+use FFMpeg\Tests\TestCase;
+
+class WatermarkFilterTest extends TestCase
+{
+    public function testApplyWatermark()
+    {
+        $stream = new Stream(array('width' => 320, 'height' => 240, 'codec_type' => 'video'));
+        $streams = new StreamCollection(array($stream));
+
+        $video = $this->getVideoMock();
+
+        $format = $this->getMock('FFMpeg\Format\VideoInterface');
+
+        $filter = new WatermarkFilter(__DIR__ . '/../../files/watermark.png');
+        $this->assertEquals(array('-vf', 'overlay 0:0'), $filter->apply($video, $format));
+
+        // check size of video is unchanged
+        $this->assertEquals(320, $stream->get('width'));
+        $this->assertEquals(240, $stream->get('height'));
+    }
+
+    public function testDifferentCoordinaates()
+    {
+        $video = $this->getVideoMock();
+        $format = $this->getMock('FFMpeg\Format\VideoInterface');
+
+        // test position absolute
+        $filter = new WatermarkFilter(__DIR__ . '/../../files/watermark.png', array(
+            'position' => 'absolute',
+            'x' => 10, 'y' => 5
+        ));
+        $this->assertEquals(array('-vf', 'overlay 10:5'), $filter->apply($video, $format));
+
+        // test position relative
+        $filter = new WatermarkFilter(__DIR__ . '/../../files/watermark.png', array(
+            'position' => 'relative',
+            'bottom' => 10, 'left' => 5
+        ));
+        $this->assertEquals(array('-vf', 'overlay 5:main_h - 10 - overlay_h'), $filter->apply($video, $format));
+
+        // test position relative
+        $filter = new WatermarkFilter(__DIR__ . '/../../files/watermark.png', array(
+            'position' => 'relative',
+            'bottom' => 5, 'right' => 4
+        ));
+        $this->assertEquals(array('-vf', 'overlay main_w - 4 - overlay_w:main_h - 5 - overlay_h'), $filter->apply($video, $format));
+
+        // test position relative
+        $filter = new WatermarkFilter(__DIR__ . '/../../files/watermark.png', array(
+            'position' => 'relative',
+            'left' => 5, 'top' => 11
+        ));
+        $this->assertEquals(array('-vf', 'overlay 5:11'), $filter->apply($video, $format));
+    }
+}