Add filter priorities

src/FFMpeg/Filters/Audio/AudioResamplableFilter.php

@@ -18,10 +18,21 @@ class AudioResamplableFilter implements AudioFilterInterface
 {
     /** @var string */
     private $rate;
+    /** @var integer */
+    private $priority;
 
-    public function __construct($rate)
+    public function __construct($rate, $priority = 0)
     {
         $this->rate = $rate;
+        $this->priority = $priority;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getPriority()
+    {
+        return $this->priority;
     }
 
     /**

src/FFMpeg/Filters/Audio/SimpleFilter.php

@@ -0,0 +1,34 @@
+<?php
+
+namespace FFMpeg\Filters\Audio;
+
+use FFMpeg\Media\Audio;
+use FFMpeg\Format\AudioInterface;
+
+class SimpleFilter implements AudioFilterInterface
+{
+    private $params;
+    private $priority;
+
+    public function __construct(array $params, $priority = 0)
+    {
+        $this->params = $params;
+        $this->priority = $priority;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getPriority()
+    {
+        return $this->priority;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function apply(Audio $audio, AudioInterface $format)
+    {
+        return $this->params;
+    }
+}

src/FFMpeg/Filters/FilterInterface.php

@@ -13,4 +13,10 @@ namespace FFMpeg\Filters;
 
 interface FilterInterface
 {
+    /**
+     * Returns the priority of the filter.
+     *
+     * @return integer
+     */
+    public function getPriority();
 }

src/FFMpeg/Filters/FiltersCollection.php

@@ -13,6 +13,7 @@ namespace FFMpeg\Filters;
 
 class FiltersCollection implements \Countable, \IteratorAggregate
 {
+    private $sorted;
     private $filters = array();
 
     /**
@@ -22,7 +23,8 @@ class FiltersCollection implements \Countable, \IteratorAggregate
      */
     public function add(FilterInterface $filter)
     {
-        $this->filters[] = $filter;
+        $this->filters[$filter->getPriority()][] = $filter;
+        $this->sorted = null;
 
         return $this;
     }
@@ -32,7 +34,11 @@ class FiltersCollection implements \Countable, \IteratorAggregate
      */
     public function count()
     {
-        return count($this->filters);
+        if (0 === count($this->filters)) {
+            return 0;
+        }
+
+        return count(call_user_func_array('array_merge', $this->filters));
     }
 
     /**
@@ -40,6 +46,11 @@ class FiltersCollection implements \Countable, \IteratorAggregate
      */
     public function getIterator()
     {
-        return new \ArrayIterator($this->filters);
+        if (null === $this->sorted) {
+            krsort($this->filters);
+            $this->sorted = call_user_func_array('array_merge', $this->filters);
+        }
+
+        return new \ArrayIterator($this->sorted);
     }
 }

src/FFMpeg/Filters/Video/ResizeFilter.php

@@ -28,12 +28,23 @@ class ResizeFilter implements VideoFilterInterface
     private $mode;
     /** @var Boolean */
     private $forceStandards;
+    /** @var integer */
+    private $priority;
 
-    public function __construct(Dimension $dimension, $mode = self::RESIZEMODE_FIT, $forceStandards = true)
+    public function __construct(Dimension $dimension, $mode = self::RESIZEMODE_FIT, $forceStandards = true, $priority = 0)
     {
         $this->dimension = $dimension;
         $this->mode = $mode;
         $this->forceStandards = $forceStandards;
+        $this->priority = $priority;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getPriority()
+    {
+        return $this->priority;
     }
 
     /**

src/FFMpeg/Filters/Video/SynchronizeFilter.php

@@ -19,6 +19,21 @@ use FFMpeg\Media\Video;
  */
 class SynchronizeFilter implements VideoFilterInterface
 {
+    private $priority;
+
+    public function __construct($priority = 12)
+    {
+        $this->priority = $priority;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getPriority()
+    {
+        return $this->priority;
+    }
+
     /**
      * {@inheritdoc}
      */

src/FFMpeg/Filters/Video/VideoResampleFilter.php

@@ -19,11 +19,21 @@ class VideoResampleFilter implements VideoFilterInterface
 {
     private $rate;
     private $gop;
+    private $priority;
 
-    public function __construct(FrameRate $rate, $gop)
+    public function __construct(FrameRate $rate, $gop, $priority = 0)
     {
         $this->rate = $rate;
         $this->gop = $gop;
+        $this->priority = $priority;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getPriority()
+    {
+        return $this->priority;
     }
 
     /**