Graphics
|
|
|
|
<?php
//
// class.image.php
// version 1.0.0, 2004-08-16
//
// Description
//
// A PHP library of helpful image processing methods. This class does not
// need to be instantiated.
//
// Author
//
// Andrew Collington, 2004
// php@amnuts.com, http://php.amnuts.com/
//
// Feedback
//
// There is message board at the following address:
//
// http://php.amnuts.com/forums/index.php
//
// Please use that to post up any comments, questions, bug reports, etc. You
// can also use the board to show off your use of the script.
//
// License
//
// This class is available free of charge for personal or non-profit work. If
// you are using it in a commercial setting, please contact php@amnuts.com for
// payment and licensing terms.
//
// Support
//
// If you like this script, or any of my others, then please take a moment
// to consider giving a donation. This will encourage me to make updates and
// create new scripts which I would make available to you. If you would like
// to donate anything, then there is a link from my website to PayPal.
//
// Examples
//
// $img = imagecreatefromjpeg('original.jpg');
// Image::colourise($img, '4c63f2');
// imagejpeg($img, 'processed.jpg', 90);
//
// $img = imagecreatefromjpeg('original.jpg');
// Image::threshold($img, 128);
// imagejpeg($img, 'processed.jpg', 90);
//
// $img = imagecreatefromjpeg('original.jpg');
// Image::greyscale($img);
// imagejpeg($img, 'processed.jpg', 90);
//
// $hex = '#45F2C3';
// $hls = Image::rgb2hls(Image::hex2rgb($hex));
// $hls[0] = 192;
// $hls[2] = 0.15;
// echo Image::rgb2hex(Image::hls2rgb($hls));
//
class Image
{
/**
* Gathers the GD version information
*
* Sometimes a check for the GD version like this:
*
* (function_exists('imagecreatetruecolor')) ? 2 : 1;
*
* can fail. This method retrieves the GD information based on what PHP
* reports to be installed. It can return the parsed version as an array,
* or just the major version if you want to do a simple check.
*
* @return int|array
* @param bool $justMajor
* @access public
*/
function getGDVersion($justMajor = true)
{
static $version = array();
if (empty($version)) {
ob_start();
phpinfo();
$buffer = ob_get_contents();
ob_end_clean();
if (preg_match('|<B>GD Version</B></td><TD ALIGN="left">([^<]*)</td>|i', $buffer, $matches)) {
$version = explode('.', $matches[1]);
} else if (preg_match('|GD Version </td><td class="v">bundled (([^ ]*)|i', $buffer, $matches)) {
$version = explode('.', $matches[1]);
} else if (preg_match('|GD Version </td><td class="v">([^ ]*)|i', $buffer, $matches)) {
$version = explode('.', $matches[1]);
}
}
return ($justMajor) ? $version[0] : $version;
}
/**
* Return an RGB colour value array of the pixel at given location.
*
* The array is returned as: array(0 => r, 1 => g, 2 => b)
*
* @return array
* @param resource &$im a reference to the image
* @param int $x coordinate
* @param int $y coordinate
* @access public
*/
function getPixelRGB(&$im, $x, $y)
{
$rgb = imagecolorat($im, $x, $y);
return array(($rgb >> 16) & 0xFF, ($rgb >> 8) & 0xFF, $rgb & 0xFF);
}
/**
* A simple metric for colour distance in RGB space
*
* The arrays are expected to be of the format:
* array(0 => r, 1 => g, 2 => b)
*
* @return float
* @param array $rgb1
* @param array $rgb2
* @access public
*/
function colourDistance($rgb1, $rgb2)
{
return sqrt(3 * ($rgb2[0] - $rgb1[0]) * ($rgb2[0] - $rgb1[0]) + 4 * ($rgb2[1] - $rgb1[1]) *
($rgb2[1] - $rgb1[1]) + 2 * ($rgb2[2] - $rgb1[2]) * ($rgb2[2] - $rgb1[2]));
}
/**
* Convert a hex colour string into an rgb array.
*
* Handles colour string in the following formats:
*
* o #44FF55
* o 4FF55
* o #4F5
* o 4F5
*
* @return array
* @param string $hex
* @access public
*/
function hex2rgb($hex)
{
$hex = @preg_replace('/^#/', '', $hex);
if (strlen($hex) == 3) {
$v = explode(':', chunk_split($hex, 1, ':'));
return array(16 * hexdec($v[0]) + hexdec($v[0]), 16 * hexdec($v[1]) + hexdec($v[1]), 16 * hexdec($v[2]) + hexdec($v[2]));
} else {
$v = explode(':', chunk_split($hex, 2, ':'));
return array(hexdec($v[0]), hexdec($v[1]), hexdec($v[2]));
}
}
/**
* Convert an rgb array into a hex colour string.
*
* Handles colour string in the following formats:
*
* o #44FF55
* o 4FF55
* o #4F5
* o 4F5
*
* @return array
* @param string $hex
* @access public
*/
function rgb2hex($rgb, $adHash = true)
{
return sprintf("%s%02X%02X%02X", ($adHash ? '#' : ''), $rgb[0], $rgb[1], $rgb[2]);
}
/**
* Convert an RGB array into HLS colour space.
*
* Expects array(r, g, b) where r, g, b in [0,255]. The HLS array is
* returned as array(h, l, s) where h is in [0,360], l and s in [0,1].
*
* Function adapted from 'Computer Graphics: Principles and Practice',
* by Foley, van Dam, Feiner and Hughes. Chapter 13; Achromatic and
* Colored Light.
*
* @return array
* @param array $rgb
* @access public
*/
function rgb2hls($rgb)
{
for ($c=0; $c<3; $c++) {
$rgb[$c] = $rgb[$c] / 255;
}
$hls = array(0, 0, 0);
$max = max($rgb);
$min = min($rgb);
$hls[1] = ($max + $min) / 2;
if ($max == $min) {
$hls[0] = null;
$hls[2] = 0;
} else {
$delta = $max - $min;
$hls[2] = ($hls[1] <= 0.5) ? ($delta / ($max + $min)) : ($delta / (2 - $delta));
if ($rgb[0] == $max) {
$hls[0] = ($rgb[1] - $rgb[2]) / $delta;
} else if ($rgb[1] == $max) {
$hls[0] = 2 + ($rgb[2] - $rgb[0]) / $delta;
} else {
$hls[0] = 4 + ($rgb[0] - $rgb[1]) / $delta;
}
$hls[0] *= 60;
if ($hls[0] < 0) {
$hls[0] += 360;
}
if ($hls[0] > 360) {
$hls[0] -= 360;
}
}
ksort($hls);
return $hls;
}
/**
* Convert HLS colour space array to RGB colour space.
*
* Expects HLS array as array(h, l, s) where h in [0,360], l and s each
* in [0,1]. Returns array(r, g, b) where r, g, and b each in [0, 255]
*
* Function adapted from 'Computer Graphics: Principles and Practice',
* by Foley, van Dam, Feiner and Hughes. Chapter 13; Achromatic and
* Colored Light.
*
* @return array
* @param array $hls
* @access public
*/
function hls2rgb($hls)
{
$rgb = array(0, 0, 0);
$m2 = ($hls[1] <= 0.5) ? ($hls[1] * (1 + $hls[2])) : ($hls[1] + $hls[2] * (1 - $hls[1]));
$m1 = 2 * $hls[1] - $m2;
if (!$hls[2]) {
if ($hls[0] === null) {
$rgb[0] = $rgb[1] = $rgb[2] = $hls[1];
} else {
return false;
}
} else {
$rgb[0] = Image::_hVal($m1, $m2, $hls[0] + 120);
$rgb[1] = Image::_hVal($m1, $m2, $hls[0]);
$rgb[2] = Image::_hVal($m1, $m2, $hls[0] - 120);
}
for ($c=0; $c<3; $c++) {
$rgb[$c] = round($rgb[$c] * 255);
}
return $rgb;
}
/**
* Hue value checker for HSL colour space routine.
*
* @return float
* @param float $n1
* @param float $n2
* @param float $h
* @access private
* @see Image::hls2rgb()
*/
function _hVal($n1, $n2, $h)
{
if ($h > 360) {
$h -= 360;
} else if ($h < 0) {
$h += 360;
}
if ($h < 60) {
return $n1 + ($n2 - $n1) * $h / 60;
} else if ($h < 180) {
return $n2;
} else if ($h < 240) {
return $n1 + ($n2 - $n1) * (240 - $h) / 60;
} else {
return $n1;
}
}
/**
* Convert an RGB array into HSV (aka HSB) colour space.
*
* Expects array(r, g, b) where r, g, b in [0,255]. The HSV array is
* returned as array(h, s, v) where h is in [0,360], s and v in [0,1].
*
* Function adapted from 'Computer Graphics: Principles and Practice',
* by Foley, van Dam, Feiner and Hughes. Chapter 13; Achromatic and
* Colored Light.
*
* @return array
* @param array $rgb
* @access public
*/
function rgb2hsv($rgb)
{
for ($c=0; $c<3; $c++) {
$rgb[$c] = $rgb[$c] / 255;
}
$hsv = array(0, 0, 0);
$max = max($rgb);
$min = min($rgb);
$hsv[2] = $max;
$hsv[1] = ($max) ? (($max - $min) / $max) : 0;
if (!$hsv[1]) {
$hsv[0] = null;
} else {
$delta = $max - $min;
if ($rgb[0] == $max) {
$hsv[0] = ($rgb[1] - $rgb[2]) / $delta;
} else if ($rgb[1] == $max) {
$hsv[0] = 2 + ($rgb[2] - $rgb[0]) / $delta;
} else {
$hsv[0] = 4 + ($rgb[0] - $rgb[1]) / $delta;
}
$hsv[0] *= 60;
if ($hsv[0] < 0) {
$hsv[0] += 360;
}
}
ksort($hsv);
return $hsv;
}
/**
* Convert HSV colour space array to RGB colour space.
*
* Expects HLS array as array(h, s, v) where h in [0,360], s and v each
* in [0,1]. Returns array(r, g, b) where r, g, and b each in [0, 255]
*
* Function adapted from 'Computer Graphics: Principles and Practice',
* by Foley, van Dam, Feiner and Hughes. Chapter 13; Achromatic and
* Colored Light.
*
* @return array
* @param array $hsv
* @access public
*/
function hsv2rgb($hsv)
{
if (!$hsv[1]) {
if ($hsv[0] === null) {
$rgb[0] = $rgb[1] = $rgb[2] = $hsv[2];
} else {
return false;
}
} else {
if ($hsv[0] == 360) {
$hsv[0] = 0;
}
$hsv[0] /= 60;
$i = floor($hsv[0]);
$f = $hsv[0] - $i;
$p = $hsv[2] * (1 - $hsv[1]);
$q = $hsv[2] * (1 - ($hsv[1] * $f));
$t = $hsv[2] * (1 - ($hsv[1] * (1 - $f)));
switch ($i) {
case 0:
$rgb[0] = $hsv[2];
$rgb[1] = $t;
$rgb[2] = $p;
break;
case 1:
$rgb[0] = $q;
$rgb[1] = $hsv[2];
$rgb[2] = $p;
break;
case 2:
$rgb[0] = $p;
$rgb[1] = $hsv[2];
$rgb[2] = $t;
break;
case 3:
$rgb[0] = $p;
$rgb[1] = $q;
$rgb[2] = $hsv[2];
break;
case 4:
$rgb[0] = $t;
$rgb[1] = $p;
$rgb[2] = $hsv[2];
break;
case 5:
$rgb[0] = $hsv[2];
$rgb[1] = $p;
$rgb[2] = $q;
break;
}
}
for ($c=0; $c<3; $c++) {
$rgb[$c] = round($rgb[$c] * 255);
}
return $rgb;
}
/**
* Converts an image resource into a grey-scale version
*
* @return void
* @param resource &$im a reference to the image
* @access public
*/
function greyscale(&$im)
{
$sx = imagesx($im);
$sy = imagesy($im);
for ($x = 0; $x < $sx; $x++) {
for ($y = 0; $y < $sy; $y++) {
$rgb = Image::getPixelRGB($im, $x, $y);
$colour = ($rgb[0] + $rgb[1] + $rgb[2]) / 3;
imagesetpixel($im, $x, $y, imagecolorallocate($im, $colour, $colour, $colour));
}
}
}
/**
* Converts an image resource into a threshold black/white version.
*
* The threshold level is a value from 0 to 255 (black to white), and any
* pixel with a colour below that value will be turned black, and any
* pixel above that value will be turned white.
*
* @return void
* @param resource &$im a reference to the image
* @param int $level
* @access public
*/
function threshold(&$im, $level = 128)
{
$sx = imagesx($im);
$sy = imagesy($im);
$black = imagecolorallocate($im, 0, 0, 0);
$white = imagecolorallocate($im, 255, 255, 255);
for ($x = 0; $x < $sx; $x++) {
for ($y = 0; $y < $sy; $y++) {
$rgb = Image::getPixelRGB($im, $x, $y);
$intensity = ($rgb[0] + $rgb[1] + $rgb[2]) / 3;
imagesetpixel($im, $x, $y, ($intensity < $level ? $black : $white));
}
}
}
/**
* Colourises an image based on given colour.
*
* @return void
* @param resource &$im a reference to the image
* @param string|array $setColour
* @access public
* @see Image::colourise()
*/
function colorize(&$im, $setColour)
{
Image::colourise($im, $setColour);
}
/**
* Colourises an image based on given colour.
*
* The colour to use as the shade/tint can be passed and as hex colour
* string or as an RGB array.
*
* @return void
* @param resource &$im a reference to the image
* @param string|array $setColour
* @access public
*/
function colourise(&$im, $setColour)
{
if (is_string($setColour)) {
$hls = Image::rgb2hls(Image::hex2rgb($setColour));
} else {
$hls = Image::rgb2hls($setColour);
}
$sx = imagesx($im);
$sy = imagesy($im);
for ($x = 0; $x < $sx; $x++) {
for ($y = 0; $y < $sy; $y++) {
$rgb = Image::getPixelRGB($im, $x, $y);
$pxhls = Image::rgb2hls($rgb);
$pxhls[0] = $hls[0];
$pxhls[2] = $hls[2];
$rgb = Image::hls2rgb($pxhls);
imagesetpixel($im, $x, $y, imagecolorallocate($im, $rgb[0], $rgb[1], $rgb[2]));
}
}
}
}
?>
|
|
|
Usage Example
|
$img = imagecreatefromjpeg('original.jpg');
Image::colourise($img, '4c63f2');
imagejpeg($img, 'processed.jpg', 90);
$img = imagecreatefromjpeg('original.jpg');
Image::threshold($img, 128);
imagejpeg($img, 'processed.jpg', 90);
$img = imagecreatefromjpeg('original.jpg');
Image::greyscale($img);
imagejpeg($img, 'processed.jpg', 90);
$hex = '#45F2C3';
$hls = Image::rgb2hls(Image::hex2rgb($hex));
$hls[0] = 192;
$hls[2] = 0.15;
echo Image::rgb2hex(Image::hls2rgb($hls));
|
|
|
Rate This Script
|
|
|
|
Store
Your email: