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

1:	<?php
2:	/**
3:	##DOC-SIGNATURE##
4:
5:	This file is part of WideImage.
6:
7:	WideImage is free software; you can redistribute it and/or modify
8:	it under the terms of the GNU Lesser General Public License as published by
9:	the Free Software Foundation; either version 2.1 of the License, or
10:	(at your option) any later version.
11:
12:	WideImage is distributed in the hope that it will be useful,
13:	but WITHOUT ANY WARRANTY; without even the implied warranty of
14:	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15:	GNU Lesser General Public License for more details.
16:
17:	You should have received a copy of the GNU Lesser General Public License
18:	along with WideImage; if not, write to the Free Software
19:	Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
20:
21:	* @package Internal/Operations
22:	**/
23:
24:	namespace WideImage\Operation;
25:
26:	/**
27:	* Unsharp filter
28:	*
29:	* This filter was taken from http://vikjavev.no/computing/ump.php,
30:	* the original author Torstein Hønsi. Adapted to fit better within
31:	* the Wideimage package.
32:	*
33:	* @package Internal/Operations
34:	*/
35:	class Unsharp
36:	{
37:	/**
38:	* Returns sharpened image
39:	*
40:	* @param \WideImage\Image $image
41:	* @param float $amount
42:	* @param int $radius
43:	* @param float $threshold
44:	* @return \WideImage\Image
45:	*/
46:	public function execute($image, $amount, $radius, $threshold)
47:	{
48:	// Attempt to calibrate the parameters to Photoshop:
49:	if ($amount > 500) {
50:	$amount = 500;
51:	}
52:
53:	$amount = $amount * 0.016;
54:
55:	if ($radius > 50) {
56:	$radius = 50;
57:	}
58:
59:	$radius = $radius * 2;
60:
61:	if ($threshold > 255) {
62:	$threshold = 255;
63:	}
64:
65:	$radius = abs(round($radius)); // Only integers make sense.
66:
67:	if ($radius == 0) {
68:	return $image;
69:	}
70:
71:	// Gaussian blur matrix
72:	$matrix = array(
73:	array(1, 2, 1),
74:	array(2, 4, 2),
75:	array(1, 2, 1)
76:	);
77:
78:	$blurred = $image->applyConvolution($matrix, 16, 0);
79:
80:	if ($threshold > 0) {
81:	// Calculate the difference between the blurred pixels and the original
82:	// and set the pixels
83:	for ($x = 0; $x < $image->getWidth(); $x++) {
84:	for ($y = 0; $y < $image->getHeight(); $y++) {
85:	$rgbOrig = $image->getRGBAt($x, $y);
86:	$rOrig = $rgbOrig["red"];
87:	$gOrig = $rgbOrig["green"];
88:	$bOrig = $rgbOrig["blue"];
89:
90:	$rgbBlur = $blurred->getRGBAt($x, $y);
91:	$rBlur = $rgbBlur["red"];
92:	$gBlur = $rgbBlur["green"];
93:	$bBlur = $rgbBlur["blue"];
94:
95:	// When the masked pixels differ less from the original
96:	// than the threshold specifies, they are set to their original value.
97:	$rNew = (abs($rOrig - $rBlur) >= $threshold)
98:	? max(0, min(255, ($amount * ($rOrig - $rBlur)) + $rOrig))
99:	: $rOrig;
100:	$gNew = (abs($gOrig - $gBlur) >= $threshold)
101:	? max(0, min(255, ($amount * ($gOrig - $gBlur)) + $gOrig))
102:	: $gOrig;
103:	$bNew = (abs($bOrig - $bBlur) >= $threshold)
104:	? max(0, min(255, ($amount * ($bOrig - $bBlur)) + $bOrig))
105:	: $bOrig;
106:	$rgbNew = array("red" => $rNew, "green" => $gNew, "blue" => $bNew, "alpha" => 0);
107:
108:	if (($rOrig != $rNew) \|\| ($gOrig != $gNew) \|\| ($bOrig != $bNew)) {
109:	$image->setRGBAt($x, $y, $rgbNew);
110:	}
111:	}
112:	}
113:	} else {
114:	$w = $image->getWidth();
115:	$h = $image->getHeight();
116:
117:	for ($x = 0; $x < $w; $x++) {
118:	for ($y = 0; $y < $h; $y++) {
119:	$rgbOrig = $image->getRGBAt($x, $y);
120:	$rOrig = $rgbOrig["red"];
121:	$gOrig = $rgbOrig["green"];
122:	$bOrig = $rgbOrig["blue"];
123:
124:	$rgbBlur = $blurred->getRGBAt($x, $y);
125:	$rBlur = $rgbBlur["red"];
126:	$gBlur = $rgbBlur["green"];
127:	$bBlur = $rgbBlur["blue"];
128:
129:	$rNew = static::bit(($amount * ($rOrig - $rBlur)) + $rOrig);
130:	$gNew = static::bit(($amount * ($gOrig - $gBlur)) + $gOrig);
131:	$bNew = static::bit(($amount * ($bOrig - $bBlur)) + $bOrig);
132:	$rgbNew = array("red" => $rNew, "green" => $gNew, "blue" => $bNew, "alpha" => 0);
133:
134:	$image->setRGBAt($x, $y, $rgbNew);
135:	}
136:	}
137:	}
138:
139:	return $image;
140:	}
141:
142:	protected static function bit($val)
143:	{
144:	if ($val > 255) {
145:	return 255;
146:	}
147:
148:	if ($val < 0) {
149:	return 0;
150:	}
151:
152:	return $val;
153:	}
154:	}
155:

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