Bug #12618: unable to select colors using palette of (loaded ) pngs or gifs
| From: | frank dot loeffler at uni-jena dot de | Date: | Tue, 07 Aug 2001 13:06:16 +0000 |
| Subject: | Bug #12618: unable to select colors using palette of (loaded ) pngs or gifs | ||
| Groups: | php.dev | ||
| Request: | Send a blank email to php-dev+get-62408@lists.php.net to get a copy of this message | ||
From: frank.loeffler@uni-jena.de
Operating system: Debian Woody
PHP version: 4.0.4pl1
PHP Bug Type: GD related
Bug description: unable to select colors using palette of (loaded ) pngs or gifs
Hi,
It maybe is a problem of concept. I do not have any knowledge about the
inside, but think of following problem:
Imagine a image, saved as png and loaded with ImageCreateFromPNG. The image
has maybe 2 different colors (to be simple), but with the same RGB-value.
Ok, this does not seem to make sense, but think of a more complicated
situation.
You can get a color handle from a loaded image only with imagecolorexact or
imagecolorclosest. Both functions would maybe return the unwanted color.
So, the problem of concept as I said is maybe the kind of 'save' the image.
In a GIF I think you have a palette, so to say a table with an index and
for each index you have the RGB-values. In the image itself only the index
of a color is saved. If you now 'save' the image in the way, that you save
for each pixel the RGB-values and so do not need a palette, you loose
information. If this is the case here, I do not know a solution to the
problem that is simple. Then maybe close this bug, but please confirm it.
If it is not, then a function ImageColorExtractByIndex or something similar
would be fine.
Thanks for work on PHP, Frank
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Edit bug report at: http://bugs.php.net/?id=12618&edit=1