Bug #5984

Cropping GIF-images

Details

Request #5984	Cropping GIF-images
Submitted	2005-11-16 13:40 UTC
From	eh at escio dot no
Assigned	davidc
Status	Closed
Package	Image_Transform
PHP Version	Irrelevant
OS	Irrelevant
Roadmaps	(Not assigned)

Comments

[2005-11-16 13:40 UTC] eh at escio dot no

Description:
------------
When using the IM-driver, ImageMagick have trouble cropping GIF-images correctly. The problem is due to IM's handling of GIF-images. For more information see: http://www.cit.gu.edu.au/~anthony/graphics/imagick6/crop/

Solutions:

Driver/IM.php, function crop():
Add "+repage" as the last command

From:
$this->command['crop'] = '-crop '
. ((int) $width) . 'x' . ((int) $height)
. '+' . ((int) $x) . '+' . ((int) $y);

To:
$this->command['crop'] = '-crop '
. ((int) $width) . 'x' . ((int) $height)
. '+' . ((int) $x) . '+' . ((int) $y) . ' +repage';

This will remove any page information from the GIF-file. Alternatively one should add an extra parameter to the crop-function so that the user can control this behaviour himself.

[2005-11-16 13:49 UTC] eh at escio dot no

For recent versions of ImageMagick (ImageMagick version 6.2.4+) instead of the +repage command prepend the -crop command with ! like this:

Driver/IM.php, function crop():

From:
$this->command['crop'] = '-crop '
. ((int) $width) . 'x' . ((int) $height)
. '+' . ((int) $x) . '+' . ((int) $y);

To:
$this->command['crop'] = '-crop '
. ((int) $width) . 'x' . ((int) $height)
. '+' . ((int) $x) . '+' . ((int) $y) . '!'

[2007-05-01 08:15 UTC] eh at escio dot no

No, I think this should be solved in IM.php, at least with a workaround.