From:
Operating system:
PHP version: 5.4.0RC8
Package: GD related
Bug Type: Bug
Bug description:imagegammacorrect function loses alpha channel
Description:
------------
When issuing imagegammacorrect function on an image resource that has alpha
channel, the alpha channel gets lost.
I looked at the source of 5.4.0RC8 and have also made a minor patch that
adds
alpha channel support by modifying the ext/gd/gd.c file.
Test script:
---------------
$img = imagecreatefrompng('input.png');
imagegammacorrect($img, 1.0, 1.0);
imagepng($img, 'result.png');
Expected result:
----------------
I would expect to see output.png retain its alpha channel.
Actual result:
--------------
The result file does not have any transparency, since the current source
code
indeed does not do gamma correction to alpha channel.
--
Edit bug report at https://bugs.php.net/bug.php?id=61221&edit=1
--
Try a snapshot (PHP 5.4):
https://bugs.php.net/fix.php?id=61221&r=trysnapshot54
Try a snapshot (PHP 5.3):
https://bugs.php.net/fix.php?id=61221&r=trysnapshot53
Try a snapshot (trunk):
https://bugs.php.net/fix.php?id=61221&r=trysnapshottrunk
Fixed in SVN:
https://bugs.php.net/fix.php?id=61221&r=fixed
Fixed in SVN and need be documented:
https://bugs.php.net/fix.php?id=61221&r=needdocs
Fixed in release:
https://bugs.php.net/fix.php?id=61221&r=alreadyfixed
Need backtrace:
https://bugs.php.net/fix.php?id=61221&r=needtrace
Need Reproduce Script:
https://bugs.php.net/fix.php?id=61221&r=needscript
Try newer version:
https://bugs.php.net/fix.php?id=61221&r=oldversion
Not developer issue:
https://bugs.php.net/fix.php?id=61221&r=support
Expected behavior:
https://bugs.php.net/fix.php?id=61221&r=notwrong
Not enough info:
https://bugs.php.net/fix.php?id=61221&r=notenoughinfo
Submitted twice:
https://bugs.php.net/fix.php?id=61221&r=submittedtwice
register_globals:
https://bugs.php.net/fix.php?id=61221&r=globals
PHP 4 support discontinued:
https://bugs.php.net/fix.php?id=61221&r=php4
Daylight Savings: https://bugs.php.net/fix.php?id=61221&r=dst
IIS Stability:
https://bugs.php.net/fix.php?id=61221&r=isapi
Install GNU Sed:
https://bugs.php.net/fix.php?id=61221&r=gnused
Floating point limitations:
https://bugs.php.net/fix.php?id=61221&r=float
No Zend Extensions:
https://bugs.php.net/fix.php?id=61221&r=nozend
MySQL Configuration Error:
https://bugs.php.net/fix.php?id=61221&r=mysqlcfg
