Re: Reading only RGB portion of an image, file_get_conents minus file headers etc
| From: | Matijn Woudt | Date: | Mon, 23 Jan 2012 13:26:00 +0000 |
| Subject: | Re: Reading only RGB portion of an image, file_get_conents minus file headers etc | ||
| References: | 1 | Groups: | php.general |
| Request: | Send a blank email to php-general+get-316356@lists.php.net to get a copy of this message | ||
On Mon, Jan 23, 2012 at 1:51 PM, Nicholas Cooper <nicholas@twpagency.com> wrote:
> Hi everyone,
>
> I've created an image in RGB from ImageMagick, it's 4 by 4 so I'm
> expecting 48 numbers (4*4*3). [width*height*(R,G,B)]
>
> When I read the file with PHP and unpack it I get between 330 and 333,
> I guess this difference is down to headers and end of file data. Is
> there anyway to access only the useful image bits, those 48 numbers?
>
> Thank you,
>
> Nicholas Cooper
>
Hi,
The easiest way is probably using imagecolorat[1]. Just do a nested
for loop over x and y values, and call imagecolorat for each pixel.
Matijn
[1] www.php.net/imagecolorat