#39353 [Opn->Bgs]: more imagecopyresized() alpha problems

ID: 39353 Updated by: pajoye@php.net Reported By: seth at pricepages dot org -Status: Open +Status: Bogus Bug Type: GD related Operating System: Mac 10.4 PHP Version: 5CVS-2006-11-02 (snap) Assigned To: pajoye New Comment: "Shouldn't it be default?" Backward compatibility... GD is an old library. But things are getting better. No bug > bogus. Previous Comments: ------------------------------------------------------------------------ [2006-11-04 17:48:46] seth at pricepages dot org Oh! No, I didn't realize imagesavealpha() existed. Why is saving the alpha a separate function? Shouldn't it be default? ------------------------------------------------------------------------ [2006-11-04 17:45:05] seth at pricepages dot org I am simply trying to enlarge the original image. I can't find a work-around in PHP, but I can create the image in Adobe Photoshop. This is what I'm attempting to create: http://pricepages.org/temp/partialTrans2.png By the way, this image is the outline of Bermuda. :) ------------------------------------------------------------------------ [2006-11-04 17:42:49] pajoye@php.net Another thing you may not know is how to preserve the alpha channel information on save: http://blog.thepimp.net/misc/bug39353_with_alpha.png you have to use imagesavealpha($img,true); before calling imagepng. ------------------------------------------------------------------------ [2006-11-04 17:26:18] pajoye@php.net "I thought that a color with alpha = 127 will produce the same results as a color marked as transparent. I want the contents of $small to overwrite everything in $img. This is not correct?" But this color (imagecolortransparent($small)) *IS* the transparent color and is ignored on copy. http://blog.thepimp.net/misc/bug39353_out.png is it not what you expect? If not, provide an image to show what you expect. ------------------------------------------------------------------------ [2006-11-04 17:11:55] seth at pricepages dot org Also, if you alter the transparency of a color to be 64, and you fill the image with that color, shouldn't the final image have a transparency of 64? imagecolorsforindex() gives the correct alpha value, but the "true color" PNG produced in my browser has no partial transparency. (it is all opaque) The code that I am using looks like this: ... $img = imagecreatetruecolor($width, $height); $red = imagecolorallocatealpha($img, 255,0,0, 64); imagefill($img, 0,0, $red); imagealphablending($img, false); /* var_dump(imagecolorsforindex($img, imagecolorat($img, 0,0))); exit; //*/ header('Content-Type: image/png'); ... ------------------------------------------------------------------------ The remainder of the comments for this report are too long. To view the rest of the comments, please view the bug report online at http://bugs.php.net/39353 -- Edit this bug report at http://bugs.php.net/?id=39353&edit=1