Simlest way converting from CMYK to RGB:
<?php
if ($jpeg->getImageColorspace() == \Imagick::COLORSPACE_CMYK) {
$jpeg->transformimagecolorspace(\Imagick::COLORSPACE_SRGB);
}
?>
It is pretty work in current stable Image Magick (6.9.0-4).
(PECL imagick 2, PECL imagick 3)
Imagick::setImageColorspace — Configure l'espace de couleurs de l'image
Configure l'espace de couleurs de l'image. Cette méthode doit être utilisée lors de la création de nouvelles images. Pour changer l'espace de couleurs d'une image existante, vous devez utiliser la méthode Imagick::transformImageColorspace().
Retourne true en cas de succès.
Lance une exception ImagickException si une erreur survient.
Simlest way converting from CMYK to RGB:
<?php
if ($jpeg->getImageColorspace() == \Imagick::COLORSPACE_CMYK) {
$jpeg->transformimagecolorspace(\Imagick::COLORSPACE_SRGB);
}
?>
It is pretty work in current stable Image Magick (6.9.0-4).When converting from CMYK to RGB using this function, the image can become inverted. To fix this, use a workaround (don't forget to download the .icc files online):
<?php
// don't use this (it inverts the image)
// $img->setImageColorspace (imagick::COLORSPACE_RGB);
if ($img->getImageColorspace() == Imagick::COLORSPACE_CMYK) {
$profiles = $img->getImageProfiles('*', false);
// we're only interested if ICC profile(s) exist
$has_icc_profile = (array_search('icc', $profiles) !== false);
// if it doesnt have a CMYK ICC profile, we add one
if ($has_icc_profile === false) {
$icc_cmyk = file_get_contents(dirname(__FILE__).'/USWebUncoated.icc');
$img->profileImage('icc', $icc_cmyk);
unset($icc_cmyk);
}
// then we add an RGB profile
$icc_rgb = file_get_contents(dirname(__FILE__).'/sRGB_v4_ICC_preference.icc');
$img->profileImage('icc', $icc_rgb);
unset($icc_rgb);
}
$img->stripImage (); // this will drop down the size of the image dramatically (removes all profiles)
?>FYI, here is the breakdown for (int $colorspace):
Constants:
0 - UndefinedColorspace
1 - RGBColorspace
2 - GRAYColorspace
3 - TransparentColorspace
4 - OHTAColorspace
5 - LABColorspace
6 - XYZColorspace
7 - YCbCrColorspace
8 - YCCColorspace
9 - YIQColorspace
10 - YPbPrColorspace
11 - YUVColorspace
12 - CMYKColorspace
13 - sRGBColorspace
14 - HSBColorspace
15 - HSLColorspace
16 - HWBColorspaceI have a better solution for solving inverted colors on php 5.3.x than posted. All the other solutions I found darkens the image or messes with the colors.
See below (note: my imagick object is $jpeg)
$range = $jpeg->getQuantumRange();
$php_vs_arr = preg_split("/\./", phpversion());
$php_vs = $php_vs_arr[0] . '.' . $php_vs_arr[1];
if ($jpeg->getImageColorspace() == Imagick::COLORSPACE_CMYK) {
//make sure cmyk color-space is set correctly
$jpeg->setImageColorspace(12);
// then we add an RGB profile
$icc_rgb = file_get_contents(FRAMEWORK_PATH . DS . 'color' . DS . 'AdobeRGB1998.icc');
$jpeg->profileImage('icc', $icc_rgb);
unset($icc_rgb);
//set color space to rgb
$jpeg->setImageColorspace(13);
//fix gamma, hue, saturation, brightness
if($php_vs < 5.3) {
//ADJUST GAMMA BY 20% for 5.2.x
$jpeg->levelImage(0, 2.0, $range['quantumRangeString']);
} else {
//php 5.3 hack FOR INVERTED COLORS
$jpeg->negateImage(false, Imagick::CHANNEL_ALL);
}
}
$jpeg->stripImage();
//end convert to RGB=========================|These are the basic steps to convert an image from RGB to CMYK:
$image = new Imagick();
$image->readImage(rgb.jpg);
$image->setImageColorSpace(Imagick::COLORSPACE_CMYK);
$image->profileImage('icc', file_get_contents(/path/CoatedFOGRA27.icc'));
$image->negateImage(FALSE, imagick::COLOR_CYAN);
$image->negateImage(FALSE, imagick::COLOR_MAGENTA);
$image->negateImage(FALSE, imagick::COLOR_YELLOW);
$image->negateImage(FALSE, imagick::COLOR_BLACK);
$image->writeImage(cmyk.rgb);This is how to Monochrome a jpg [on Windows].. since I couldn't find it anywhere else.
<?php
header("Content-type: image/jpeg");
$IMagick = new IMagick('c:\\testing\\fruit.jpg');
$IMagick->setImageColorSpace(Imagick::COLORSPACE_GRAY);
echo $IMagick;
?>If your getting strange/bad color rendering from a PDF, after trying the colorspace constants noted by jdstraughan, try other values outside that range.
In one case for me only $image->setImageColorSpace(22) provided useful color. I have found posts elsewhere using values up to 255.These are the basic steps to convert an image from RGB to CMYK:
$image = new Imagick();
$image->readImage(rgb.jpg);
$image->setImageColorSpace(Imagick::COLORSPACE_CMYK);
$image->profileImage('icc', file_get_contents(/path/CoatedFOGRA27.icc'));
$image->negateImage(FALSE, imagick::COLOR_CYAN);
$image->negateImage(FALSE, imagick::COLOR_MAGENTA);
$image->negateImage(FALSE, imagick::COLOR_YELLOW);
$image->negateImage(FALSE, imagick::COLOR_BLACK);
$image->writeImage(cmyk.rgb);
For more information:
http://www.cesarebordi.it/imagemagick-php-convertire-rgb-to-cmyk-web-developer/