[DFW.pm] Changing colors in a gif using cgi

[Matthew Musgrove]

Jerry,

You can’t just change a few bytes in an image file and be done with it.  If
you don’t want to use a module, then you’ll need to be well versed in the
various image file formats before you can ever start coding. Otherwise you
won’t know what bits to look for, much less what values to use to get the
change you are interested in.



Matt

Matt


On Tue, Jan 8, 2013 at 4:16 PM, Jerry Kassebaum <kassebaumj at hotmail.com>wrote:

>  How can I use Perl to read a non-text file in hex, change a few
> individual bytes, and write it back? Would this work to change a gif or
> png, or would I have to go down to binary?
>
> I appreciate the ImageMagic answer I received before, and may have to
> resort to that, but I would prefer to work with pure Perl without loading a
> module. Surely there is a simple way to read/write a file byte by byte?
>
>
> Jerry Kassebaum
>
>
> _______________________________________________
> Dfw-pm mailing list
> Dfw-pm at pm.org
> http://mail.pm.org/mailman/listinfo/dfw-pm
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.pm.org/pipermail/dfw-pm/attachments/20130108/b43b2e63/attachment.html>