
Recherche avancée
Autres articles (111)
-
Les autorisations surchargées par les plugins
27 avril 2010, parMediaspip core
autoriser_auteur_modifier() afin que les visiteurs soient capables de modifier leurs informations sur la page d’auteurs -
Script d’installation automatique de MediaSPIP
25 avril 2011, parAfin de palier aux difficultés d’installation dues principalement aux dépendances logicielles coté serveur, un script d’installation "tout en un" en bash a été créé afin de faciliter cette étape sur un serveur doté d’une distribution Linux compatible.
Vous devez bénéficier d’un accès SSH à votre serveur et d’un compte "root" afin de l’utiliser, ce qui permettra d’installer les dépendances. Contactez votre hébergeur si vous ne disposez pas de cela.
La documentation de l’utilisation du script d’installation (...) -
Support de tous types de médias
10 avril 2011Contrairement à beaucoup de logiciels et autres plate-formes modernes de partage de documents, MediaSPIP a l’ambition de gérer un maximum de formats de documents différents qu’ils soient de type : images (png, gif, jpg, bmp et autres...) ; audio (MP3, Ogg, Wav et autres...) ; vidéo (Avi, MP4, Ogv, mpg, mov, wmv et autres...) ; contenu textuel, code ou autres (open office, microsoft office (tableur, présentation), web (html, css), LaTeX, Google Earth) (...)
Sur d’autres sites (10313)
-
ffmpeg : Factorize video resampling.
30 août 2011, par Alex Converseffmpeg : Factorize video resampling.
-
PHP FFmpeg video aspect ratio problem [SOLVED]
29 août 2011, par Herr Kaleuni compiled the new version of FFMPEG and the padding commands have been deprecated.
As i try to get familiar with the new -vf pad= commands, i want to ask, how can i
convert a video without changing it's aspect ratio.I've checked numerous solutions from stackoverflow, nothing seemed to work.
Can someone, please post a working PHP example or cmd line. I would be VERY happy.Please note that the videos in question, could be 4:3 and also be 16:9
Let's say, i convert a 16:9 video to 640x480 format. It will need some bars at
the top and at the bottom. That is what i want to do.Thanks
EDIT :
I solved the problem on my own. The FFmpeg documentation is a little bit weird so
you have to experiment yourself a little bit.
The padding formula is like :$pad_horizontal = $target_width + $pad_left + $pad_right;
$pad_vertical = $target_height;
// blah
$command .= " -vf pad=$pad_horizontal:$pad_vertical:". $pad_left .":". $pad_top .":black";Pay special attention at the $pad_vertical part since the paddings there are better
not added so that the padding calculation of ffmpeg is not broken.Here is the full source code to the demo
<?
/***********************************************************************************
get_dimensions()
Takes in a set of video dimensions - original and target - and returns the optimal conversion
dimensions. It will always return the smaller of the original or target dimensions.
For example: original dimensions of 320x240 and target dimensions of 640x480.
The result will be 320x240 because converting to 640x480 would be a waste of disk
space, processing, and bandwidth (assuming these videos are to be downloaded).
@param $original_width: The actual width of the original video file which is to be converted.
@param $original_height: The actual height of the original video file which is to be converted.
@param $target_width: The width of the video file which we will be converting to.
@param $target_height: The height of the video file which we will be converting to.
@param $force_aspect: Boolean value of whether or not to force conversion to the target's
aspect ratio using padding (so the video isn't stretched). If false, the
conversion dimensions will retain the aspect ratio of the original.
Optional parameter. Defaults to true.
@return: An array containing the size and padding information to be used for conversion.
Format:
Array
(
[width] => int
[height] => int
[padtop] => int // top padding (if applicable)
[padbottom] => int // bottom padding (if applicable)
[padleft] => int // left padding (if applicable)
[padright] => int // right padding (if applicable)
)
***********************************************************************************/
function get_dimensions($original_width,$original_height,$target_width,$target_height,$force_aspect)
{
if(!isset($force_aspect))
{
$force_aspect = true;
}
// Array to be returned by this function
$target = array();
$target['padleft'] = 0;
$target['padright'] = 0;
$target['padbottom'] = 0;
$target['padtop'] = 0;
// Target aspect ratio (width / height)
$aspect = $target_width / $target_height;
// Target reciprocal aspect ratio (height / width)
$raspect = $target_height / $target_width;
if($original_width/$original_height !== $aspect)
{
// Aspect ratio is different
if($original_width/$original_height > $aspect)
{
// Width is the greater of the two dimensions relative to the target dimensions
if($original_width < $target_width)
{
// Original video is smaller. Scale down dimensions for conversion
$target_width = $original_width;
$target_height = round($raspect * $target_width);
}
// Calculate height from width
$original_height = round($original_height / $original_width * $target_width);
$original_width = $target_width;
if($force_aspect)
{
// Pad top and bottom
$dif = round(($target_height - $original_height) / 2);
$target['padtop'] = $dif;
$target['padbottom'] = $dif;
}
}
else
{
// Height is the greater of the two dimensions relative to the target dimensions
if($original_height < $target_height)
{
// Original video is smaller. Scale down dimensions for conversion
$target_height = $original_height;
$target_width = round($aspect * $target_height);
}
//Calculate width from height
$original_width = round($original_width / $original_height * $target_height);
$original_height = $target_height;
if($force_aspect)
{
// Pad left and right
$dif = round(($target_width - $original_width) / 2);
$target['padleft'] = $dif;
$target['padright'] = $dif;
}
}
}
else
{
// The aspect ratio is the same
if($original_width !== $target_width)
{
if($original_width < $target_width)
{
// The original video is smaller. Use its resolution for conversion
$target_width = $original_width;
$target_height = $original_height;
}
else
{
// The original video is larger, Use the target dimensions for conversion
$original_width = $target_width;
$original_height = $target_height;
}
}
}
if($force_aspect)
{
// Use the target_ vars because they contain dimensions relative to the target aspect ratio
$target['width'] = $target_width;
$target['height'] = $target_height;
}
else
{
// Use the original_ vars because they contain dimensions relative to the original's aspect ratio
$target['width'] = $original_width;
$target['height'] = $original_height;
}
return $target;
}
function get_vid_dim($file)
{
$command = '/usr/bin/ffmpeg -i ' . escapeshellarg($file) . ' 2>&1';
$dimensions = array();
exec($command,$output,$status);
if (!preg_match('/Stream #(?:[0-9\.]+)(?:.*)\: Video: (?P<videocodec>.*) (?P<width>[0-9]*)x(?P<height>[0-9]*)/',implode("\n",$output),$matches))
{
preg_match('/Could not find codec parameters \(Video: (?P<videocodec>.*) (?P<width>[0-9]*)x(?P<height>[0-9]*)\)/',implode("\n",$output),$matches);
}
if(!empty($matches['width']) && !empty($matches['height']))
{
$dimensions['width'] = $matches['width'];
$dimensions['height'] = $matches['height'];
}
return $dimensions;
}
$command = '/usr/bin/ffmpeg -i ' . $src . ' -ab 96k -b 700k -ar 44100 -f flv -s ' . '640x480 -acodec mp3 '. $video_output_dir . $video_filename . ' 2>&1';
define( 'VIDEO_WIDTH', '640' );
define( 'VIDEO_HEIGHT', '480' );
$src_1 = getcwd() .'/'. 'test_video1.mpeg';
$video_filename1 = 'video1.flv';
$src_2 = getcwd() .'/'. 'test_video2.mp4';
$video_filename2 = 'video2.flv';
$src_3 = getcwd() .'/'. 'test_video3.mp4';
$video_filename3 = 'video3.flv';
convert_video( $src_1, $video_filename1 );
convert_video( $src_2, $video_filename2 );
convert_video( $src_3, $video_filename3 );
function convert_video( $src = '', $video_filename = '' )
{
$video_output_dir = getcwd() .'/';
@unlink ( $video_output_dir . $video_filename );
$original = get_vid_dim($src);
$target = get_dimensions( $original['width'], $original['height'], VIDEO_WIDTH, VIDEO_HEIGHT, TRUE );
echo '<pre>';
print_r( $original );
echo '</pre>';
echo '<pre>';
print_r( $target );
echo '</pre>';
$target_width = $target['width'];
$target_height = $target['height'];
$pad_left = $target['padleft'];
$pad_right = $target['padright'];
$pad_bottom = $target['padbottom'];
$pad_top = $target['padtop'];
$pad_horizontal = $target_width + $pad_left + $pad_right;
$pad_vertical = $target_height; // + $pad_top + $pad_bottom;
$command = '/usr/bin/ffmpeg -i ' . $src;
// $command .= " -s {$target_width}x{$target_height} ";
$command .= " -vf pad=$pad_horizontal:$pad_vertical:". $pad_left .":". $pad_top .":black";
$command .= ' -ab 96k -b 700k -ar 44100';
$command .= ' -f flv ';
$command .= ' -qscale 4';
$command .= ' -ss 30';
$command .= ' -t 5';
$command .= ' -ac 2 -ab 128k -qscale 5 ';
$command .= ' ' . $video_output_dir . $video_filename;
exec( $command, $output, $status );
echo '<pre>';
print_r( $command );
echo '</pre>';
if ( $status == 0 )
{
echo '<br />Convert OK. <br />';
}
else
{
echo '<pre>';
print_r( $output );
echo '</pre>';
}
echo '<br />';
echo '<br />';
}
?>
</height></width></videocodec></height></width></videocodec>Thank you and have fun :)
-
WebM Video Codec in Skype 5.0 Group Video
9 novembre 2010, par noreply@blogger.com (John Luther)Our friends at Skype recently released Skype 5.0 for Windows and Mac, which features a beta group video feature using VP8, the video codec in WebM. In the first half of 2010, approximately 40% of Skype-to-Skype calls were video calls and we’re excited that in the future many of those calls will be made using VP8.
To check out the new group video feature, simply download the Skype Software.
Note : For group video to work, everyone on the call needs the new Skype for Windows or Mac, a webcam and a broadband connection.
For more info about Skype group video, visit the Skype website.