Merge pull request #5 from nlegoff/review

Review

docs/source/Recipes.rst

@@ -73,14 +73,24 @@ Simple transcoding
 
 To transcode a video, you have to pass the target format to FFMpeg.
 
+When you define a format which implements the
+:ref:`Resizable <resizable-reference>` interface.
+You must set FFprobe (see :ref:`FF-probe<ffprobe-reference>`)
+for probing the media and found its height and size.
+
 The following example initialize a Ogg format and encodes a `Video.mpeg` to a
 target file `file.ogv` :
 
 .. code-block:: php
 
     <?php
+    use FFMpeg\FFProbe;
     use FFMpeg\Format\Video\Ogg;
 
+    $ffprobe = FFProbe::load($logger);
+
+    $ffmpeg->setProber($ffprobe);
+
     $oggFormat = new Ogg();
 
     $ffmpeg->open('Video.mpeg')
@@ -178,6 +188,8 @@ Advanced media type
 This section presents usage for the different interfaces. You can combine
 them for your own formats.
 
+.. _resizable-reference:
+
 Resizable
 .........
 
@@ -207,13 +219,15 @@ The example below resizes a video by half.
         ->encode($format, 'file.mp4')
         ->close();
 
+.. _resamplable-reference:
 
 Resamplable
 ...........
 
 This interface provides video resampling. The example below resample the video
 at 15 frame per second with a I-frame every 30 image (see
-`GOP on wikipedia <https://wikipedia.org/wiki/Group_of_pictures>`_).
+`GOP on wikipedia <https://wikipedia.org/wiki/Group_of_pictures>`_) and supports
+B-frames (see `B-frames on wikipedia <https://wikipedia.org/wiki/Video_compression_picture_types>`_)
 
 .. code-block:: php
 
@@ -234,6 +248,10 @@ at 15 frame per second with a I-frame every 30 image (see
             return 30;
         }
 
+        public function supportBFrames()
+        {
+            return true;
+        }
     }
 
     $format = new MyFormat();
@@ -477,6 +495,8 @@ latest AvConv / FFMPeg version, aac encoding has to be executed with extra comma
         ->encode($format, 'output-aac.mp4')
         ->close();
 
+.. _ffprobe-reference:
+
 FFProbe recipes
 ---------------
 

src/FFMpeg/FFMpeg.php

@@ -231,7 +231,7 @@ class FFMpeg extends Binary
 
         if ($format instanceof Video\Resizable) {
             if ( ! $this->prober) {
-                throw new LogicException('You must set a valid prober if you use RESIZEMODE_INSET');
+                throw new LogicException('You must set a valid prober if you use a resizable format');
             }
 
             $result = json_decode($this->prober->probeStreams($this->pathfile), true);
@@ -269,15 +269,22 @@ class FFMpeg extends Binary
 
         if ($format instanceof Video\Resamplable) {
             $cmd_part2 .= ' -r ' . $format->getFrameRate();
+
+            /**
+             * @see http://sites.google.com/site/linuxencoding/x264-ffmpeg-mapping
+             */
+            if ($format->supportBFrames()) {
+                $cmd_part2 .= ' -b_strategy 1 -bf 3 -g ' . $format->getGOPSize();
+            }
         }
 
         if ($format instanceof Video\Transcodable) {
             $cmd_part2 .= ' -vcodec ' . $format->getVideoCodec();
         }
 
-        $cmd_part2 .= ' -b ' . $format->getKiloBitrate() . 'k -g 25 -bf 3'
+        $cmd_part2 .= ' -b ' . $format->getKiloBitrate() . 'k'
             . ' -threads ' . $threads
-            . ' -refs 6 -b_strategy 1 -coder 1 -qmin 10 -qmax 51 '
+            . ' -refs 6 -coder 1 -qmin 10 -qmax 51 '
             . ' -sc_threshold 40 -flags +loop -cmp +chroma'
             . ' -me_range 16 -subq 7 -i_qfactor 0.71 -qcomp 0.6 -qdiff 4 '
             . ' -trellis 1 -qscale 1 '

src/FFMpeg/Format/Dimension.php

@@ -33,7 +33,7 @@ class Dimension
     public function __construct($width, $height)
     {
         if ($width <= 0 || $height <= 0) {
-            throw InvalidArgumentException('Width and height should be positive integer');
+            throw new InvalidArgumentException('Width and height should be positive integer');
         }
 
         $this->width = (int) $width;

src/FFMpeg/Format/Video/DefaultVideo.php

@@ -97,8 +97,13 @@ abstract class DefaultVideo extends DefaultAudio implements Interactive, Resampl
                 break;
             case self::RESIZEMODE_FIT:
             default:
+                if (null !== $this->width && null !== $this->height) {
                     $width = $this->width;
                     $height = $this->height;
+                } else {
+                    $width = $originalWidth;
+                    $height = $originalHeight;
+                }
                 break;
         }
 

src/FFMpeg/Format/Video/Resamplable.php

@@ -30,9 +30,20 @@ interface Resamplable extends BaseVideo
      */
     public function getFrameRate();
 
+    /**
+     * Returns true if the current format supports B-Frames
+     *
+     * @see https://wikipedia.org/wiki/Video_compression_picture_types
+     *
+     * @return Boolean
+     */
+    public function supportBFrames();
+
     /**
      * Returns the GOP size
      *
+     * @see https://wikipedia.org/wiki/Group_of_pictures
+     *
      * @return integer
      */
     public function getGOPSize();