Question

How to create a youtube like video preview? That is in youtube, it is showing the preview of the video when we mouseover the progress bar? How to do that kind of preview using ffmpeg or mencoder or is there any other way to do that? Have a look at this image. Please go here for a live preview.

http://www.youtube.com/watch?v=yto4_QFoLdA&feature=watch-now-button&wide=1

Answer 1

You can use the ffmpeg extension. Below is some ancient code that I wrote to choose six thumbnails from a video.

The notable parts are:

$frame = $vid->getFrame(); // pull a frame from the video
$gd = $frame->toGDImage(); // turn the frame into a GD image
imagejpeg($gd, "filename.jpg", 70); // save jpeg of the frame using 70% quality

---

$vid = new ffmpeg_movie ( $fileName );
$frameRate = $vid->getFrameRate ();
$gapSize = max(10,$vid->getDuration()-10) * $frameRate / 6;
$n = 0; $curFrame = 5 * $frameRate;
while ( $n != 6 ) {
    $f = $vid->getFrame ( $curFrame );
    if ((1==$curFrame && false!==$f) || false !== ($f = $vid->getNextKeyFrame ())) {
        $thumbnails [$n] = array (
            'path' => "muveethumb-$muveeId-$n.jpg", 
            'time' => ceil ( ($vid->getFrameNumber () - 1) * 1000 / $frameRate ) 
        );
        $gd = $f->toGDImage ();
        imagejpeg ( $gd, $targetFolder.$thumbnails [$n] ['path'], 70 );
        ++ $n;
        $curFrame += $gapSize;
    } elseif ($n > 0) {
        while ( $n != 6 ) {
            $thumbnails [] = $thumbnails [$n - 1];
            ++ $n;
        }
    } else {
        if ($curFrame!=1) {
            // attempt to get first frame as a last resort
            $curFrame = 1;
        } else {
            // unless we already tried that
            throw new Exception ( "Could not create thumbnails" );
        }
    }
}