Add metadata to audio files - feature

src/FFMpeg/Filters/Audio/AddMetadataFilter.php

@@ -0,0 +1,42 @@
+<?php
+namespace FFMpeg\Filters\Audio;
+
+use FFMpeg\Filters\Audio\AudioFilterInterface;
+use FFMpeg\Format\AudioInterface;
+use FFMpeg\Media\Audio;
+
+class AddMetadataFilter implements AudioFilterInterface
+{	
+	/** @var Array */
+	private $metaArr;
+
+	function __construct($data = null)
+	{
+		$this->metaArr = $data;
+	}
+
+	public function getPriority()
+	{
+		//must be of high priority in case theres a second input stream (artwork) to register with audio
+		return 9;
+	}
+
+	public function apply(Audio $audio, AudioInterface $format)
+	{
+		if (is_null($this->metaArr))
+			return ['-map_metadata', '-1', '-vn'];
+
+		$metadata = [];
+
+		if (array_key_exists("artwork", $this->metaArr)) {
+			array_push($metadata, "-i", $this->metaArr['artwork'], "-map", "0", "-map", "1");
+			unset($this->metaArr['artwork']);
+		}
+
+		foreach ($this->metaArr as $k => $v) {
+			array_push($metadata, "-metadata", "$k=$v");
+		}
+
+		return $metadata;
+	}
+}

src/FFMpeg/Filters/Audio/AudioFilters.php

@@ -2,6 +2,7 @@
 
 namespace FFMpeg\Filters\Audio;
 
+use FFMpeg\Filters\Audio\AddMetadataFilter;
 use FFMpeg\Media\Audio;
 
 class AudioFilters
@@ -26,4 +27,25 @@ class AudioFilters
 
         return $this;
     }
+
+    /**
+     * Add metadata to an audio file. If no arguments are given then filter
+     * will remove all metadata from the audio file
+     * @param Array|Null $data  If array must contain one of these key/value pairs:
+     *    - "title": Title metadata
+     *    - "artist": Artist metadata
+     *    - "composer": Composer metadata
+     *    - "album": Album metadata
+     *    - "track": Track metadata
+     *    - "artwork": Song artwork. String of file path
+     *    - "year": Year metadata
+     *    - "genre": Genre metadata
+     *    - "description": Description metadata
+     */
+    public function addMetadata($data = null)
+    {
+        $this->media->addFilter(new AddMetadataFilter($data));
+
+        return $this;
+    }
 }