PHP 图片 平均分割

$filename = 'D://WWW/1.jpg';

$p = 5;

// Get new sizes

list($width, $height) = getimagesize($filename);

$newwidth = $width;

$newheight = floor($height / $p);

$last = $height % $p;

// Load

$source = imagecreatefromjpeg($filename);

for( $i=0 ; $i< $p; $i++ ){

	$_p = $newheight*$i;

	if( ( $i + 1 ) == $p )

		$newheight += $last;

	$thumb = ImageCreateTrueColor($newwidth, $newheight);

	imagecopyresized( $thumb, $source, 0, 0, 0, $_p, $newwidth,  $height, $width, $height);

	imagejpeg( $thumb , "./t{$i}.jpg" ,100);

}

将图片平均分成几份。