Valla, sin querer queriendo encontre en php.net una función que calcula el tamaño del borde negro, si les sirve aca esta:
http://www.php.net/manual/en/function.imagecolorat.php Código PHP:
<?php
define("DEBUG_OUT",TRUE);
$border_size = find_border_size($path);
print_r($border_size);
/*
* $border = max(find_border_size("img.jpg"));
* $thumb_size_x = 180+(2*$border);
* $thumb_size_y = 240+(2*$border);
* $thumb_size = $thumb_size_x . "x" . $thumb_size_y; (String to use in the -s param of ffmpeg)
* $crop_cmd = "-croptop $border -cropbottom $border -cropright $border -cropleft $border";
*/
function find_border_size($path)
{
/* The pad var is essentially a 'feather' value. Unless one of the RGB values rises
* above $pad we are saying to continue. You can try different values but with 10 I
* would still get a decent sized border due to the bleedover of the movie into
* the hat.
*/
$pad = 20;
$border_y = 0;
$border_x = 0;
if(!file_exists($path))
{
if(DEBUG_OUT) echo("Error: $path not found.\n");
return FALSE;
}
else
{
if(DEBUG_OUT) echo("Opening: $path ...\n");
}
$im = @imagecreatefromjpeg($path);
if(!$im) return FALSE;
$height = imagesy($im);
$width = imagesx($im);
/* Let's start at 0, 0 and keep going till we hit a color */
if(DEBUG_OUT) echo("Image - Height: $height / Width: $width\n");
/* Border Height(Y) */
$center_width = ceil($width/2);
for($i=0; $i<$height; $i++)
{
$rgb = imagecolorat($im,$center_width,$i);
$r = ($rgb >> 16) & 0xFF;
$g = ($rgb >> 8) & 0xFF;
$b = $rgb & 0xFF;
if(DEBUG_OUT) echo("Height: ($center_width,$i) R: $r / G: $g / B: $b\n");
if($r >= $pad || $g >= $pad || $b >= $pad)
{
$border_y = $i;
if($border_y == $height) $border_y = 0;
break;
}
}
/* Border Width(X) */
$center_height = ceil($height/2);
for($i=0; $i<$width; $i++)
{
$rgb = imagecolorat($im,$i,$center_height);
$r = ($rgb >> 16) & 0xFF;
$g = ($rgb >> 8) & 0xFF;
$b = $rgb & 0xFF;
if(DEBUG_OUT) echo("Width: ($i,$center_width) R: $r / G: $g / B: $b\n");
if($r >= $pad || $g >= $pad || $b >= $pad)
{
$border_x = $i;
if($border_x == $width) $border_x = 0;
break;
}
}
/* I am making the border a multiple of 2 since I am sending these values to FFMpeg */
if($border_x != 0)
{
$border_x /= 2;
$border_x = round($border_x);
$border_x *= 2;
}
if($border_y != 0)
{
$border_y /= 2;
$border_y = round($border_y);
$border_y *= 2;
}
if(DEBUG_OUT) echo("Border Width: $border_x / Border Height: $border_y\n");
return array($border_x,$border_y);
}
?>