Hello Friends,
i 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 />';
}
?>
Thank you and have fun :)