Code Examples -> Imagefilter function - There are servers with GD library but not bundled with PHP. Imagefilter, will not work if the GD library is not bundled. So here is the code that will do exactly what imagefilter do.

	Join us on FaceBook
	Submit Your Code
	Poker Tournaments
	Poker Guide for Developers
	SEO Monitor
	UpTime Monitor
	My Favorite Examples
	My Favorite Articles
	Update Your Profile

More Weber Sites
	PHP Code Search
	Web Development Forums
	Learn MySQL Playing Trivia
	PHPBB2 Templates
	Web Development Resources
	Web Development Content
	Internet Security Software

Recommended Links
	PHPClasses
	PHP Editor
	PHP Jobs
	Vision.To Design
	Ajax Tutorials
	PHP Programming Help
	PHP/MySQL Programming
	Webmaster Resources
	Webmaster Forum
	XML meta language
	website builder

Recommended
	פרייסז - הכח לקנות עובר לידיים שלך
	Texas Holdem Poker Evangelists


BACK		ADD A COMMENT		SEND TO A FRIEND		ADD TO MY FAVORITES		ADD CODE EXAMPLES		PRINT

PHP Code Examples

Title :	Imagefilter function - There are servers with GD library but not bundled with PHP. Imagefilter, will not work if the GD library is not bundled. So here is the code that will do exactly what imagefilter do.
Categories :	PHP, GD image library, Graphics	Chao Xu
Date :	Mar 13th 2007
Grade :	3 of 5 (graded 3 times)
Viewed :	3466
File :	No file for this code example.
Images :	No Images for this code example.

Search :	More code by Chao Xu
Action :	Grade This Code Example
Tools :	My Examples List

Code


Like this code? Show the author your appreciation.

Some of the code is part of the GD's original code into PHP

<?php
//include this file whenever you have to use imageconvolution…
//you can use in your project, but keep the comment below
//great for any image manipulation library
//Made by Chao Xu(Mgccl) 3/1/07
//www.webdevlogs.com
//V 1.0
if(!function_exists(‘imagefilter’)){
function imagefilter($source, $var, $arg1 = null, $arg2 = null, $arg3 = null){
#define(’IMAGE_FILTER_NEGATE’,0);
#define(’IMAGE_FILTER_GRAYSCALE’,0);
#define(’IMAGE_FILTER_BRIGHTNESS’,2);
#define(’IMAGE_FILTER_CONTRAST’,3);
#define(’IMAGE_FILTER_COLORIZE’,4);
#define(’IMAGE_FILTER_EDGEDETECT’,5);
#define(’IMAGE_FILTER_EMBOSS’,6);
#define(’IMAGE_FILTER_GAUSSIAN_BLUR’,7);
#define(’IMAGE_FILTER_SELECTIVE_BLUR’,8);
#define(’IMAGE_FILTER_MEAN_REMOVAL’,9);
#define(’IMAGE_FILTER_SMOOTH’,10);
$max_y = imagesy($source);
$max_x = imagesx($source);
switch ($var){
case 0:
$y = 0;
while($y<$max_y) {
$x = 0;
while($x<$max_x){
$rgb = imagecolorat($source,$x,$y);
$r = 255 - (($rgb >> 16) & 0xFF);
$g = 255 - (($rgb >> 8) & 0xFF);
$b = 255 - ($rgb & 0xFF);
$a = $rgb >> 24;
$new_pxl = imagecolorallocatealpha($source, $r, $g, $b, $a);
if ($new_pxl == false){
$new_pxl = imagecolorclosestalpha($source, $r, $g, $b, $a);
}
imagesetpixel($source,$x,$y,$new_pxl);
++$x;
}
++$y;
}
return true;
break;
case 1:
$y = 0;
while($y<$max_y) {
$x = 0;
while($x<$max_x){
$rgb = imagecolorat($source,$x,$y);
$a = $rgb >> 24;
$r = ((($rgb >> 16) & 0xFF)*0.299)+((($rgb >> 8) & 0xFF)*0.587)+(($rgb & 0xFF)*0.114);
$new_pxl = imagecolorallocatealpha($source, $r, $r, $r, $a);
if ($new_pxl == false){
$new_pxl = imagecolorclosestalpha($source, $r, $r, $r, $a);
}
imagesetpixel($source,$x,$y,$new_pxl);
++$x;
}
++$y;
}
return true;
break;
case 2:
$y = 0;
while($y<$max_y) {
$x = 0;
while($x<$max_x){
$rgb = imagecolorat($source,$x,$y);
$r = (($rgb >> 16) & 0xFF) + $arg1;
$g = (($rgb >> 8) & 0xFF) + $arg1;
$b = ($rgb & 0xFF) + $arg1;
$a = $rgb >> 24;
$r = ($r > 255)? 255 : (($r < 0)? 0:$r);
$g = ($g > 255)? 255 : (($g < 0)? 0:$g);
$b = ($b > 255)? 255 : (($b < 0)? 0:$b);
$new_pxl = imagecolorallocatealpha($source, $r, $g, $b, $a);
if ($new_pxl == false){
$new_pxl = imagecolorclosestalpha($source, $r, $g, $b, $a);
}
imagesetpixel($source,$x,$y,$new_pxl);
++$x;
}
++$y;
}
return true;
break;
case 3:
$contrast = pow((100-$arg1)/100,2);
$y = 0;
while($y<$max_y) {
$x = 0;
while($x<$max_x){
$rgb = imagecolorat($source,$x,$y);
$a = $rgb >> 24;
$r = (((((($rgb >> 16) & 0xFF)/255)-0.5)*$contrast)+0.5)*255;
$g = (((((($rgb >> 8) & 0xFF)/255)-0.5)*$contrast)+0.5)*255;
$b = ((((($rgb & 0xFF)/255)-0.5)*$contrast)+0.5)*255;
$r = ($r > 255)? 255 : (($r < 0)? 0:$r);
$g = ($g > 255)? 255 : (($g < 0)? 0:$g);
$b = ($b > 255)? 255 : (($b < 0)? 0:$b);
$new_pxl = imagecolorallocatealpha($source, $r, $g, $b, $a);
if ($new_pxl == false){
$new_pxl = imagecolorclosestalpha($source, $r, $g, $b, $a);
}
imagesetpixel($source,$x,$y,$new_pxl);
++$x;
}
++$y;
}
return true;
break;
case 4:
$x = 0;
while($x<$max_x){
$y = 0;
while($y<$max_y){
$rgb = imagecolorat($source, $x, $y);
$r = (($rgb >> 16) & 0xFF) + $arg1;
$g = (($rgb >> 8) & 0xFF) + $arg2;
$b = ($rgb & 0xFF) + $arg3;
$a = $rgb >> 24;
$r = ($r > 255)? 255 : (($r < 0)? 0:$r);
$g = ($g > 255)? 255 : (($g < 0)? 0:$g);
$b = ($b > 255)? 255 : (($b < 0)? 0:$b);
$new_pxl = imagecolorallocatealpha($source, $r, $g, $b, $a);
if ($new_pxl == false){
$new_pxl = imagecolorclosestalpha($source, $r, $g, $b, $a);
}
imagesetpixel($source,$x,$y,$new_pxl);
++$y;
}
++$x;
}
return true;
break;
case 5:
return imageconvolution($source, array(array(-1,0,-1), array(0,4,0), array(-1,0,-1)), 1, 127);
break;
case 6:
return imageconvolution($source, array(array(1.5, 0, 0), array(0, 0, 0), array(0, 0, -1.5)), 1, 127);
break;
case 7:
return imageconvolution($source, array(array(1, 2, 1), array(2, 4, 2), array(1, 2, 1)), 16, 0);
break;
case 8:
for($y = 0; $y<$max_y; $y++) {
for ($x = 0; $x<$max_x; $x++) {
$flt_r_sum = $flt_g_sum = $flt_b_sum = 0;
$cpxl = imagecolorat($source, $x, $y);
for ($j=0; $j<3; $j++) {
for ($i=0; $i<3; $i++) {
if (($j == 1) && ($i == 1)) {
$flt_r[1][1] = $flt_g[1][1] = $flt_b[1][1] = 0.5;
} else {
$pxl = imagecolorat($source, $x-(3>>1)+$i, $y-(3>>1)+$j);

$new_a = $pxl >> 24;
//$r = (($pxl >> 16) & 0xFF);
//$g = (($pxl >> 8) & 0xFF);
//$b = ($pxl & 0xFF);
$new_r = abs((($cpxl >> 16) & 0xFF) - (($pxl >> 16) & 0xFF));
if ($new_r != 0) {
$flt_r[$j][$i] = 1/$new_r;
} else {
$flt_r[$j][$i] = 1;
}

$new_g = abs((($cpxl >> 8) & 0xFF) - (($pxl >> 8) & 0xFF));
if ($new_g != 0) {
$flt_g[$j][$i] = 1/$new_g;
} else {
$flt_g[$j][$i] = 1;
}

$new_b = abs(($cpxl & 0xFF) - ($pxl & 0xFF));
if ($new_b != 0) {
$flt_b[$j][$i] = 1/$new_b;
} else {
$flt_b[$j][$i] = 1;
}
}

$flt_r_sum += $flt_r[$j][$i];
$flt_g_sum += $flt_g[$j][$i];
$flt_b_sum += $flt_b[$j][$i];
}
}

for ($j=0; $j<3; $j++) {
for ($i=0; $i<3; $i++) {
if ($flt_r_sum != 0) {
$flt_r[$j][$i] /= $flt_r_sum;
}
if ($flt_g_sum != 0) {
$flt_g[$j][$i] /= $flt_g_sum;
}
if ($flt_b_sum != 0) {
$flt_b[$j][$i] /= $flt_b_sum;
}
}
}

$new_r = $new_g = $new_b = 0;

for ($j=0; $j<3; $j++) {
for ($i=0; $i<3; $i++) {
$pxl = imagecolorat($source, $x-(3>>1)+$i, $y-(3>>1)+$j);
$new_r += (($pxl >> 16) & 0xFF) * $flt_r[$j][$i];
$new_g += (($pxl >> 8) & 0xFF) * $flt_g[$j][$i];
$new_b += ($pxl & 0xFF) * $flt_b[$j][$i];
}
}

$new_r = ($new_r > 255)? 255 : (($new_r < 0)? 0:$new_r);
$new_g = ($new_g > 255)? 255 : (($new_g < 0)? 0:$new_g);
$new_b = ($new_b > 255)? 255 : (($new_b < 0)? 0:$new_b);
$new_pxl = ImageColorAllocateAlpha($source, (int)$new_r, (int)$new_g, (int)$new_b, $new_a);
if ($new_pxl == false) {
$new_pxl = ImageColorClosestAlpha($source, (int)$new_r, (int)$new_g, (int)$new_b, $new_a);
}
imagesetpixel($source,$x,$y,$new_pxl);
}
}
return true;
break;
case 9:
return imageconvolution($source, array(array(-1,-1,-1),array(-1,9,-1),array(-1,-1,-1)), 1, 0);
break;
case 10:
return imageconvolution($source, array(array(1,1,1),array(1,$arg1,1),array(1,1,1)), $arg1+8, 0);
break;
}
}
}
?>

Related Code Examples

	crop and resize image class using gd library function Categories : PHP, PHP Classes, GD image library, Graphics
	Generate image with random number (CAPTCHA) Categories : PHP, GD image library, Graphics, Security
	Simple class that uses GD to draw pie charts. After the class definition there's some sample code to demonstrate how you use the class. Categories : Graphics, PHP, PHP Classes, GD image library, Charts and Graphs
	Create a Thumbnail Using PHP, GD and Exif Categories : PHP, Graphics, Exif, GD image library
	Create Thumbnails - resize an image - jpeg, jpg, gif, png to the specifed width and height in proportion without loosing out on pixcel quality. Categories : PHP, GD image library, Graphics
	PHP Email image generator - hide your email from bots - using the GD Library Categories : PHP, Graphics, GD image library, Beginner Guides
	Advanced Image WaterMarker Categories : PHP, PHP Classes, GD image library, Graphics, Object Oriented
	Image Generation Class ( PNG Format ) Categories : PHP, GD image library, PHP Classes, Graphics
	A captcha image allows you to prevent spam posting when users reload the page and stop bots from submitting forms automatically. This version allows you to use your own fonts (.ttf) to show the text. Categories : PHP, Security, Graphics, GD image library
	Simple PHP Bar Graph using GD library Categories : PHP, GD image library, Graphics, Arrays
	EasyPhpThumbnail Class - The EasyPhpThumbnail class allows you to generate thumbnails and handle image manipulation for GIF, JPG and PNG on-the-fly. Categories : PHP, PHP Classes, Object Oriented, Graphics, GD image library
	PHP Image Compression using GD library Categories : PHP, Compression, GD image library, Graphics
	a simple pie-chart in php3 (with gd) Categories : PHP, Graphics, GD image library, Charts and Graphs
	Line graphics generation library written in PHP + GD library (spanish comments) Categories : PHP, Graphics, GD image library
	CAPTCHA[Image verification] Categories : PHP, Security, GD image library, Graphics, Sessions