Re: [WM]: Help with the GIF file format

["Dr Johann A. Briffa" <jabrif@eng.um.edu.mt>]

Chad W. Davis wrote:
> I always thought that the terminating bytes for a GIF file were 00 3B. 
> However, I have found more often than not that a GIF file may contain 
> many instances of 00 3B before these terminating bytes.  Is there a 
> more reliable way to find the size of the image and where the true 
> end-of-image indicator lies?
> 
> My reason for asking this is: what if information (like
> steganography) is appended past the end-of-image indicator?  How can 
> you determine this if there are many instances of 00 3B?

you can always decode the image and once you've read enough source-coded data to determine all pixels, then you're done. everything
else is redundant.
Johann
--
________________________________________________________________________
Dr Johann A. Briffa                     http://www.eng.um.edu.mt/~jabrif
Communications and Computer Engineering            Phone: +356 2340-2078
University of Malta, Msida MSD 06, Malta           Fax:   +356 2134-3577


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