From: seth at pricepages dot org Operating system: Mac 10.4 PHP version: 5.1.4 PHP Bug Type: GD related Bug description: Patch for Bug 30863
Description: ------------ This small patch fixes the bug outlined in 30863 (http://bugs.php.net/bug.php?id=30863 ). The problem is a one pixel shift of the transparency. A one pixel border on one side remains the default color. Caution: this fix strikes me as *too* simple. I'm worried that I'm breaking something that I'm not noticing. Original code (gd.c line ~1331): /* If the pixel is transparent, we assign it the palette index that * will later be added at the end of the palette as the transparent * index. */ if ((oim->transparent >= 0) && (oim->transparent == * (inptr - 1))) { *outptr++ = nim->colorsTotal; inptr++; continue; } Fixed code ("inptr - 1" changed): /* If the pixel is transparent, we assign it the palette index that * will later be added at the end of the palette as the transparent * index. */ if ((oim->transparent >= 0) && (oim->transparent == (*inptr))) { *outptr++ = nim->colorsTotal; inptr++; continue; } In other news: GD's quantization << pngquant Maybe someday I'll port the code. Interest? Reproduce code: --------------- <?php $img = imagecreatetruecolor(100,100); //Start with a transparent canvas $trans = imagecolorresolve($img, 255,255,255); //Specifying a color as transparent (& below) causes the pixel shift imagecolortransparent($img, $trans); imagefilledrectangle($img, 0,0, 100,100, $trans); //Make a solid grey box $grey = imagecolorresolve($img, 128,128,128); imagefilledrectangle($img, 0,50, 100,100, $grey); //Draw a black line $black = imagecolorresolve($img, 0,0,0); imageline($img, 50,0, 50,100, $black); //Converting to palette (& above) causes a pixel shift imagetruecolortopalette($img, false, 256); imagepng($img, 'test.png'); ?> -- Edit bug report at http://bugs.php.net/?id=38226&edit=1 -- Try a CVS snapshot (PHP 4.4): http://bugs.php.net/fix.php?id=38226&r=trysnapshot44 Try a CVS snapshot (PHP 5.2): http://bugs.php.net/fix.php?id=38226&r=trysnapshot52 Try a CVS snapshot (PHP 6.0): http://bugs.php.net/fix.php?id=38226&r=trysnapshot60 Fixed in CVS: http://bugs.php.net/fix.php?id=38226&r=fixedcvs Fixed in release: http://bugs.php.net/fix.php?id=38226&r=alreadyfixed Need backtrace: http://bugs.php.net/fix.php?id=38226&r=needtrace Need Reproduce Script: http://bugs.php.net/fix.php?id=38226&r=needscript Try newer version: http://bugs.php.net/fix.php?id=38226&r=oldversion Not developer issue: http://bugs.php.net/fix.php?id=38226&r=support Expected behavior: http://bugs.php.net/fix.php?id=38226&r=notwrong Not enough info: http://bugs.php.net/fix.php?id=38226&r=notenoughinfo Submitted twice: http://bugs.php.net/fix.php?id=38226&r=submittedtwice register_globals: http://bugs.php.net/fix.php?id=38226&r=globals PHP 3 support discontinued: http://bugs.php.net/fix.php?id=38226&r=php3 Daylight Savings: http://bugs.php.net/fix.php?id=38226&r=dst IIS Stability: http://bugs.php.net/fix.php?id=38226&r=isapi Install GNU Sed: http://bugs.php.net/fix.php?id=38226&r=gnused Floating point limitations: http://bugs.php.net/fix.php?id=38226&r=float No Zend Extensions: http://bugs.php.net/fix.php?id=38226&r=nozend MySQL Configuration Error: http://bugs.php.net/fix.php?id=38226&r=mysqlcfg
