MediaFile thumbnail event hooks + VideoThumbnails plugin

The exception thrown from MediaFile will be caught and simply result in no thumbnail at all right now. In the future we might use a catch-all and have a "cannot generate preview"-icon or something. VideoThumbnails requires php5-ffmpeg and php5-gd.
2014-04-16 19:14:26 +02:00
parent 00aa3fa734
commit 06d4cecf7f
7 changed files with 197 additions and 32 deletions
--- a/plugins/VideoThumbnails/VideoThumbnailsPlugin.php
+++ b/plugins/VideoThumbnails/VideoThumbnailsPlugin.php
@@ -0,0 +1,90 @@
+<?php
+/**
+ * GNU social - a federating social network
+ *
+ * Plugin to make thumbnails of video files with ffmpeg
+ *
+ * PHP version 5
+ *
+ * LICENCE: This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * @category  Plugin
+ * @package   GNUsocial
+ * @author    Mikael Nordfeldth <mmn@hethane.se>
+ * @copyright 2014 Free Software Foundation http://fsf.org
+ * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
+ * @link      https://www.gnu.org/software/social/
+ */
+
+if (!defined('GNUSOCIAL')) { exit(1); }
+
+/*
+ * Dependencies:
+ *  php5-ffmpeg
+ *  php5-gd
+ *
+ * Video support will depend on your ffmpeg.
+ */
+
+class VideoThumbnailsPlugin extends Plugin
+{
+    /*
+     * This function should only extract an image from the video stream
+     * and disregard any scaling aspects in the resulting file, since
+     * this will be handled in the core thumbnail algorithm.
+     */
+    public function onCreateFileImageThumbnail(MediaFile $file, &$imgPath, $media=null)
+    {
+        // This might accidentally pass application/ogg videos.
+        // If that's a problem, let's fix it in the calling function.
+        if ($media !== 'video') {
+            return true;
+        }
+
+        $movie = new ffmpeg_movie($file->getPath(), false);
+
+        $frames = $movie->getFrameCount();
+        if ($frames > 0) {
+            $frame = $movie->getFrame(floor($frames/2));
+        } else {
+            $frame = $movie->getNextKeyFrame();
+        }
+
+        // We failed to get a frame.
+        if ($frame === null) {
+            return true;
+        }
+
+        // Let's save our frame to a temporary file. If we fail, remove it.
+        $imgPath = tempnam(sys_get_temp_dir(), 'socialthumb');
+        if (!imagejpeg($frame->toGDImage(), $imgPath)) {
+            @unlink($imgPath);
+            return true;
+        }
+        return false;
+    }
+
+    public function onPluginVersion(&$versions)
+    {
+        $versions[] = array('name' => 'Video Thumbnails',
+                            'version' => GNUSOCIAL_VERSION,
+                            'author' => 'Mikael Nordfeldth',
+                            'homepage' => 'https://www.gnu.org/software/social/',
+                            'rawdescription' =>
+                            // TRANS: Plugin description.
+                            _m('HTML5 media attachment support'));
+        return true;
+    }
+}
+