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PHP - Manual: Imagick::setImageColorspace

2024-12-22

Imagick::setImageColorspace

(PECL imagick 2, PECL imagick 3)

Imagick::setImageColorspaceSets the image colorspace

说明

public Imagick::setImageColorspace(int $colorspace): bool

Sets the image colorspace. This method should be used when creating new images. To change the colorspace of an existing image, you should use Imagick::transformImageColorspace().

参数

colorspace

One of the COLORSPACE constants

返回值

成功时返回 true

错误/异常

错误时抛出 ImagickException。

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User Contributed Notes 8 notes

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13
eth at ethaniel dot com
10 years ago
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)
?>
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8
pilot114 at bk dot ru
7 years ago
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).
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5
jdstraughan dot com at gmail dot com
13 years ago
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 - HWBColorspace
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1
Cesare Bordi
4 years ago
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);
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1
kevin.a.florida
9 years ago
I 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=========================|
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0
mettedraq at gmail dot com
11 years ago
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;
?>
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0
charlie at midsouthhost dot com
12 years ago
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.
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-2
cesarebordi
4 years ago
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/

官方地址:https://www.php.net/manual/en/imagick.setimagecolorspace.php

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