File class\libraries\vendor\smottt\wideimage\lib\WideImage\Operation\AddNoise.php

1:	<?php
2:	/**
3:	* @author Tomasz Kapusta
4:	* @copyright 2010
5:
6:	This file is part of WideImage.
7:
8:	WideImage is free software; you can redistribute it and/or modify
9:	it under the terms of the GNU Lesser General Public License as published by
10:	the Free Software Foundation; either version 2.1 of the License, or
11:	(at your option) any later version.
12:
13:	WideImage is distributed in the hope that it will be useful,
14:	but WITHOUT ANY WARRANTY; without even the implied warranty of
15:	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16:	GNU Lesser General Public License for more details.
17:
18:	You should have received a copy of the GNU Lesser General Public License
19:	along with WideImage; if not, write to the Free Software
20:	Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
21:
22:	* @package Internal/Operations
23:	**/
24:
25:	namespace WideImage\Operation;
26:
27:	/**
28:	* Noise filter
29:	*
30:	* @package Internal/Operations
31:	*/
32:	class AddNoise
33:	{
34:	/**
35:	* Returns image with noise added
36:	*
37:	* @param \WideImage\Image $image
38:	* @param float $amount
39:	* @param const $type
40:	* @param float $threshold
41:	* @return \WideImage\Image
42:	*/
43:	public function execute($image, $amount, $type) {
44:	switch ($type) {
45:	case 'salt&pepper':
46:	$fun = 'saltPepperNoise_fun';
47:	break;
48:	case 'color':
49:	$fun = 'colorNoise_fun';
50:	break;
51:	default :
52:	$fun = 'monoNoise_fun';
53:	break;
54:	}
55:
56:	return static::filter($image->asTrueColor(), $fun, $amount);
57:	}
58:
59:	/**
60:	* Returns image with every pixel changed by specififed function
61:	*
62:	* @param \WideImage\Image $image
63:	* @param str $function
64:	* @param int $value
65:	* @return \WideImage\Image
66:	*/
67:	public function filter($image, $function, $value)
68:	{
69:	for ($y = 0; $y < $image->getHeight(); $y++) {
70:	for ($x = 0; $x< $image->getWidth(); $x++) {
71:	$rgb = imagecolorat($image->getHandle(), $x, $y);
72:
73:	$a = ($rgb >> 24) & 0xFF;
74:	$r = ($rgb >> 16) & 0xFF;
75:	$g = ($rgb >> 8) & 0xFF;
76:	$b = $rgb & 0xFF;
77:
78:	static::$function($r, $g, $b, $value);
79:
80:	$color = imagecolorallocatealpha($image->getHandle(), $r, $g, $b, $a);
81:	imagesetpixel($image->getHandle(), $x, $y, $color);
82:	}
83:	}
84:
85:	return $image;
86:	}
87:
88:	/**
89:	* Adds color noise by altering given R,G,B values using specififed amount
90:	*
91:	* @param int $r
92:	* @param int $g
93:	* @param int $b
94:	* @param int $value
95:	* @return void
96:	*/
97:	public function colorNoise_fun(&$r, &$g, &$b, $amount)
98:	{
99:	$r = static::byte($r + mt_rand(0, $amount) - ($amount >> 1) );
100:	$g = static::byte($g + mt_rand(0, $amount) - ($amount >> 1) );
101:	$b = static::byte($b + mt_rand(0, $amount) - ($amount >> 1) );
102:	}
103:
104:	/**
105:	* Adds mono noise by altering given R,G,B values using specififed amount
106:	*
107:	* @param int $r
108:	* @param int $g
109:	* @param int $b
110:	* @param int $value
111:	* @return void
112:	*/
113:	public function monoNoise_fun(&$r, &$g, &$b, $amount)
114:	{
115:	$rand = mt_rand(0, $amount) - ($amount >> 1);
116:
117:	$r = static::byte($r + $rand);
118:	$g = static::byte($g + $rand);
119:	$b = static::byte($b + $rand);
120:	}
121:
122:	/**
123:	* Adds salt&pepper noise by altering given R,G,B values using specififed amount
124:	*
125:	* @param int $r
126:	* @param int $g
127:	* @param int $b
128:	* @param int $value
129:	* @return void
130:	*/
131:	public function saltPepperNoise_fun(&$r, &$g, &$b, $amount)
132:	{
133:	if (mt_rand(0, 255 - $amount) != 0) {
134:	return;
135:	}
136:
137:	$rand = mt_rand(0, 1);
138:
139:	switch ($rand) {
140:	case 0:
141:	$r = $g = $b = 0;
142:	break;
143:	case 1:
144:	$r = $g = $b = 255;
145:	break;
146:	}
147:	}
148:
149:	/**
150:	* Returns value within (0,255)
151:	*
152:	* @param int $b
153:	* @return int
154:	*/
155:	public function byte($b)
156:	{
157:	if ($b > 255) {
158:	return 255;
159:	}
160:
161:	if ($b < 0) {
162:	return 0;
163:	}
164:
165:	return (int) $b;
166:	}
167:	}
168:

Namespaces

Classes