Doc #71524 [Asn]: Produces only black image

Edit report at https://bugs.php.net/bug.php?id=71524&edit=1 ID: 71524 Updated by: danack@php.net Reported by: lee dot traynor at skeptic dot de Summary: Produces only black image Status: Assigned Type: Documentation Problem Package: imagick Operating System: Windows XP/7/8/10 PHP Version: 5.5.32 Assigned To: danack Block user comment: N Private report: N New Comment: > Finally why in a lot of the Imagick examples is Imagick written with a backslash in front of > it? The 'Imagick' class exists in the global namespace. When used in a different namespace, you either need to do "use Imagick;" at the top of the file, or use \Imagick to escape from that namespace to the global one. http://php.net/manual/en/language.namespaces.basics.php It seems I prefer to use slashes for classes for this case. Previous Comments: ------------------------------------------------------------------------ [2016-02-06 18:43:17] lee dot traynor at skeptic dot de That seems to work fine as in this script to emulate grain extract layer mode: $im = new Imagick (realpath ("Paihia_Sunset.jpg")); $ge = clone $im; $ge->modulateImage (100, 0, 100); $ge->blurImage (0, 15); $ge->setImageArtifact ("compose:args", "0,-1,1,0.5"); $im->compositeImage ($ge, Imagick::COMPOSITE_MATHEMATICS, 0, 0); Note that the two values in the middle apply to $ge (-1) and $im (+1) respectively. This is difficult to see from the imagemagick command line because the images have to be swapped. If you were correcting the documentation, then the line about the virtual pixels can be removed. Perhaps that will make it clearer that the artifact has to be set on the composited object. Finally why in a lot of the Imagick examples is Imagick written with a backslash in front of it? I've never found it necessary to escape "i" and "\i" has no particular significance. It just makes the examples harder to follow. Best, Lee ------------------------------------------------------------------------ [2016-02-06 12:53:22] danack@php.net I think setting the compose:args on the second image, gives the expected result: $im2->setImageArtifact ("compose:args", "1,0,-0.5,0.5"); Can you confirm? ------------------------------------------------------------------------ [2016-02-05 21:05:05] lee dot traynor at skeptic dot de The command as given on the man page: convert src1.png src2.png -compose mathematics -define compose:args="1,0,-0.5,0.5" -composite output.png works perfectly well with said version of Imagemagick (using two identical images, a somewhat brighter but greyed out image is obtained). ------------------------------------------------------------------------ [2016-02-05 20:56:39] danack@php.net Could you do me a favour and give the equivalent convert command? this is going to be an issue that I'll need to report upstream to the ImageMagick guys. ------------------------------------------------------------------------ [2016-02-04 18:22:37] lee dot traynor at skeptic dot de Description: ------------ --- From manual page: http://www.php.net/imagick.compositeimage --- The script produces only black images regardless of the values passed by setImageArtifact. imagick module version 3.4.0RC6 Imagick compiled with ImageMagick version ImageMagick 6.8.9-1 Q16 x86 2014-05-08 http://www.imagemagick.org Test script: --------------- $im1 = new Imagick (realpath ("Waikare.jpg")); $im2 = clone $im1; $im1->setImageVirtualPixelMethod (Imagick::VIRTUALPIXELMETHOD_TRANSPARENT); $im1->setImageArtifact ("compose:args", "1,0,-0.5,0.5"); $im1->compositeImage ($im2, Imagick::COMPOSITE_MATHEMATICS, 0, 0); $im1->writeImage (getcwd () . "/test.png"); echo "<img src=\"test.png\">"; Expected result: ---------------- Using the values 0,1,-1,0.5 a grey image should be produced. ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=71524&edit=1