ID: 40158 User updated by: henus at mail dot ru Reported By: henus at mail dot ru Status: Open Bug Type: GD related Operating System: Windows XP PHP Version: 5.2.0 Assigned To: pajoye New Comment:
Yes Previous Comments: ------------------------------------------------------------------------ [2007-01-19 12:02:41] [EMAIL PROTECTED] Can you *PLEASE* confirm that it works when you disable alpha blending? Answer should be Yes or No, I got the details already. I really do not have the time to explain/ask again and again the same thing. About imagefill, yes, that's a bug. Please open a new one if you like. I will fix it as soon as possible. ------------------------------------------------------------------------ [2007-01-19 11:53:03] henus at mail dot ru Yes, the is global problem with alphablending in libgd\gd.c but about "imagealphablending($mask, false); //<<< Important!": i absolutely should not care about ebabling\disabling imagealphablending before imagefilter, because of function shoud colorize image by new values of red,gree,blue (!!!there is no alpha in parameters) if IMG_FILTER_COLORIZE will have in parameters alpha, if alphablending enable, value of alpha should allow for calculation of new color values (in gdImageColor it will before new_pxl = gdImageColorAllocateAlpha(src, (int)r, (int)g, (int)b, a);) and gdImageSetPixel shoul with disabled alphablending. otherwise function work like merging of two images with alphablending. where: first image - source image from function parameters. second image - correct colorized copy of source image. it is not logically. it is incorrect. another bug in imagefill: this function not only fill image, it is also disable alphablending. php example: <? /* first colorizing */ $im1=imagecreatetruecolor(1,1); imagealphablending($im1, TRUE); $c01=imagecolorallocatealpha($im1,255,0,0,63); imagefill($im1,0,0,$c01); $c01=imagecolorsforindex($im1,imagecolorat($im1,0,0)); imagefilter($im1, IMG_FILTER_COLORIZE, -255, 255, 0); $c1=imagecolorsforindex($im1,imagecolorat($im1,0,0)); /* second colorizing */ $im2=imagecreatetruecolor(1,1); imagealphablending($im2, TRUE); $c02=imagecolorallocatealpha($im2,255,0,0,63); imagefill($im2,0,0,$c02); $c02=imagecolorsforindex($im1,imagecolorat($im1,0,0)); /* att!!! after imagefill another enabling alphablending */ imagealphablending($im2, TRUE); imagefilter($im2, IMG_FILTER_COLORIZE, -255, 255, 0); $c2=imagecolorsforindex($im2,imagecolorat($im2,0,0)); print"<br>before 1 - "; print_r($c01); print"<br>after 1 - "; print_r($c1); print"<br><br>before 2 - "; print_r($c02); print"<br>after 2 - "; print_r($c2); ?> results: before 1- Array ( [red] => 255 [green] => 0 [blue] => 0 [alpha] => 63 ) after 1 - Array ( [red] => 0 [green] => 255 [blue] => 0 [alpha] => 63 ) before 2- Array ( [red] => 0 [green] => 255 [blue] => 0 [alpha] => 63 ) after 2 - Array ( [red] => 126 [green] => 128 [blue] => 0 [alpha] => 31 ) where: after 1 - correct result of IMG_FILTER_COLORIZE, because of imagefill disable alphablending after 2 - incorrect result of IMG_FILTER_COLORIZE, because of after imagefill i manually enable alphablending disabling alphablending in code it is good solutions for gdImageColor, but after it is necessary to restore old value of alphaBlendingFlag. ------------------------------------------------------------------------ [2007-01-18 19:54:09] [EMAIL PROTECTED] "pixel from edge with coord (95,11) have wrong color. red-98 green-98 blue-164 (why is red>0 and green>0 ????????? after substracting 255???) (should be red-0 green-0 blue-102)" It is blended over the destination pixel. You have to disable alpha blending *before* the imagefilter call. This image: http://blog.thepimp.net/misc/bug40158_black_filtered_mask.png shows exactly what you are trying to do (blue, black or purple, it really does not matter), the script being: $mask=imagecreatefrompng("40158.png"); imagealphablending($mask, false); //<<< Important! imagefilter($mask, IMG_FILTER_COLORIZE, -255, -255, -255); //<<< save alpha, so we see its value imagesavealpha($mask, true); imagepng($mask,"mask1.png"); Using your last example, the resulting image is like your "result_correct3.png". ------------------------------------------------------------------------ [2007-01-18 19:37:49] henus at mail dot ru it`s not solve my problem.... :( first - about blue color - look at my submission from [18 Jan 11:03am UTC] if use imagefilter($mask, IMG_FILTER_COLORIZE, -255, -255, -255); the result is http://www.fort-ross.ru/henus/gd/result_incorrect.png with legibly visible artefacts. second - image http://blog.thepimp.net/misc/bug40158_result.png also has artefacts at the adges... pixel from edge with coord (95,11) have wrong color red-98 green-98 blue-164 (why is red>0 and green>0 ????????? after substracting 255???) (should be red-0 green-0 blue-102) third - look at my submission from [18 Jan 5:56pm UTC] why is 255-255=126???????????????? one more demo - using imagefilter($mask, IMG_FILTER_COLORIZE, -255, -255, 0); mask - http://fort-ross.ru/henus/gd/mask3.png incorrect image - http://fort-ross.ru/henus/gd/result_incorrect3.png correct image - http://fort-ross.ru/henus/gd/result_correct3.png ------------------------------------------------------------------------ [2007-01-18 18:51:59] [EMAIL PROTECTED] (rgba(255,0,0,xxx)) should have been (rgba(0,0,255,xxx)) but you noticed it :) ------------------------------------------------------------------------ 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/40158 -- Edit this bug report at http://bugs.php.net/?id=40158&edit=1