sRGB to AdobeRGB1998 keep colors

[jeffreyg]

Hello,

We have a system where the user uploads an image and it automaticly sets a sRGB color profile to the image. When I try to convert these images with Imagick to AdobeRGB1998, the colors are different. It has the correct colorprofile but the original colors are gone.

I tried repoducing these steps in Photoshop. When I assign the AdobeRGB1998 color profile to the image, the output is the same as the output of my script. When I convert the image to AdobeRGB1998 color profile, the output is the same as the orignal.

In other words I need my Imagick script to convert the color profile, instead of asigne the color profile.

Here is my code:

Code: Select all

$img->setResourceLimit(6, 4);
$img->stripImage();
$img->setImageUnits(imagick::RESOLUTION_PIXELSPERINCH);
$img->setResolution($cDPI,$cDPI);
$img->resampleImage($cDPI,$cDPI, imagick::FILTER_UNDEFINED,1.5);
$img->profileImage('icc', $icc_adobeRGB);
$img->resizeImage($cWidth,$cHeight,imagick::FILTER_LANCZOS,TRUE);
$img->writeImage($input);
$img->destroy();

Here are the images. I want my Imagick to get the same output as the original image and converted photoshop image with Adobe1998 color profile:

Orignal image wih sRGB color profile


Image generated with my Imagick script with AdobeRGB1998 color profile


Image generated with photoshop assign AdobeRGB1998 color profile


Image generated with photoshop convert to AdobeRGB1998 color profile

[snibgo]

Code: Select all

$img->stripImage();
$img->setImageUnits(imagick::RESOLUTION_PIXELSPERINCH);
$img->setResolution($cDPI,$cDPI);
$img->resampleImage($cDPI,$cDPI, imagick::FILTER_UNDEFINED,1.5);
$img->profileImage('icc', $icc_adobeRGB);

You strip the image, which removes the embedded profile. So profileImage will assign AdobeRGB. If you hadn't stripped, it would have the sRGB profile embedded, so profileImage would convert it.


EDIT: I've just noticed your query is about IMagick. My reply wrongly assumed ImageMagick. IMagick might be different.

[jeffreyg]

Hello snibgo,

Thank you for the reply. I had to use strip to change the DPI of the image and the size of the image. Couldn't get it working in any other way. I added the sRGB profile first, because you were right that it strips the image profile.

Code: Select all

$img->stripImage();
$img->setImageUnits(imagick::RESOLUTION_PIXELSPERINCH);
$img->setResolution($cDPI,$cDPI);
$img->resampleImage($cDPI,$cDPI, imagick::FILTER_UNDEFINED,1.5);
$img->profileImage('icc', $icc_sRGB);
$img->profileImage('icc', $icc_adobeRGB);

Now it works and the colors are exactly the same.