154 lines
3.7 KiB
PHP
154 lines
3.7 KiB
PHP
<?php
|
|
/**
|
|
* @author Tomasz Kapusta
|
|
* @copyright 2010
|
|
|
|
This file is part of WideImage.
|
|
|
|
WideImage is free software; you can redistribute it and/or modify
|
|
it under the terms of the GNU Lesser General Public License as published by
|
|
the Free Software Foundation; either version 2.1 of the License, or
|
|
(at your option) any later version.
|
|
|
|
WideImage is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
GNU Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public License
|
|
along with WideImage; if not, write to the Free Software
|
|
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
|
|
|
|
* @package Internal/Operations
|
|
**/
|
|
|
|
/**
|
|
* Noise filter
|
|
*
|
|
* @package Internal/Operations
|
|
*/
|
|
class WideImage_Operation_AddNoise {
|
|
/**
|
|
* Returns image with noise added
|
|
*
|
|
* @param WideImage_Image $image
|
|
* @param float $amount
|
|
* @param const $type
|
|
* @param float $threshold
|
|
* @return WideImage_Image
|
|
*/
|
|
|
|
function execute($image, $amount, $type) {
|
|
|
|
switch ($type)
|
|
{
|
|
case 'salt&pepper' : $fun = 'saltPepperNoise_fun';
|
|
break;
|
|
case 'color' : $fun = 'colorNoise_fun';
|
|
break;
|
|
default : $fun = 'monoNoise_fun';
|
|
break;
|
|
}
|
|
|
|
return self::filter($image->asTrueColor(), $fun, $amount);
|
|
}
|
|
|
|
/**
|
|
* Returns image with every pixel changed by specififed function
|
|
*
|
|
* @param WideImage_Image $image
|
|
* @param str $function
|
|
* @param int $value
|
|
* @return WideImage_Image
|
|
*/
|
|
function filter($image, $function, $value)
|
|
{
|
|
for ($y = 0; $y < $image->getHeight(); $y++)
|
|
{
|
|
for ($x = 0; $x< $image->getWidth(); $x++)
|
|
{
|
|
$rgb = imagecolorat($image->getHandle(), $x, $y);
|
|
|
|
$a = ($rgb >> 24) & 0xFF;
|
|
$r = ($rgb >> 16) & 0xFF;
|
|
$g = ($rgb >> 8) & 0xFF;
|
|
$b = $rgb & 0xFF;
|
|
|
|
|
|
self::$function($r, $g, $b, $value);
|
|
|
|
$color = imagecolorallocatealpha($image->getHandle(), $r, $g, $b, $a);
|
|
imagesetpixel($image->getHandle(), $x, $y, $color);
|
|
}
|
|
}
|
|
return $image;
|
|
}
|
|
/**
|
|
* Adds color noise by altering given R,G,B values using specififed amount
|
|
*
|
|
* @param int $r
|
|
* @param int $g
|
|
* @param int $b
|
|
* @param int $value
|
|
* @return void
|
|
*/
|
|
function colorNoise_fun(&$r, &$g, &$b, $amount)
|
|
{
|
|
$r = self::byte($r + mt_rand(0, $amount) - ($amount >> 1) );
|
|
$g = self::byte($g + mt_rand(0, $amount) - ($amount >> 1) );
|
|
$b = self::byte($b + mt_rand(0, $amount) - ($amount >> 1) );
|
|
}
|
|
/**
|
|
* Adds mono noise by altering given R,G,B values using specififed amount
|
|
*
|
|
* @param int $r
|
|
* @param int $g
|
|
* @param int $b
|
|
* @param int $value
|
|
* @return void
|
|
*/
|
|
function monoNoise_fun(&$r, &$g, &$b, $amount)
|
|
{
|
|
$rand = mt_rand(0, $amount) - ($amount >> 1);
|
|
|
|
$r = self::byte($r + $rand);
|
|
$g = self::byte($g + $rand);
|
|
$b = self::byte($b + $rand);
|
|
}
|
|
/**
|
|
* Adds salt&pepper noise by altering given R,G,B values using specififed amount
|
|
*
|
|
* @param int $r
|
|
* @param int $g
|
|
* @param int $b
|
|
* @param int $value
|
|
* @return void
|
|
*/
|
|
function saltPepperNoise_fun(&$r, &$g, &$b, $amount)
|
|
{
|
|
if (mt_rand(0, 255 - $amount) != 0) return;
|
|
|
|
$rand = mt_rand(0, 1);
|
|
switch ($rand)
|
|
{
|
|
case 0 : $r = $g = $b = 0;
|
|
break;
|
|
case 1 : $r = $g = $b = 255;
|
|
break;
|
|
}
|
|
}
|
|
/**
|
|
* Returns value within (0,255)
|
|
*
|
|
* @param int $b
|
|
* @return int
|
|
*/
|
|
function byte($b)
|
|
{
|
|
if ($b > 255) return 255;
|
|
if ($b < 0) return 0;
|
|
return (int) $b;
|
|
}
|
|
|
|
}
|