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From: "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com>
Newsgroups: sci.crypt
Subject: Re: xorpng
Date: Sun, 5 Jan 2025 15:17:42 -0800
Organization: A noiseless patient Spider
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On 1/5/2025 3:06 PM, Stefan Claas wrote:
> Chris M. Thomasson wrote:
[...]
> *Please* try to write a .ppm (P6) to .png converter (and back) in C(++)
> and see if you can get the *original* data back. The sci.crypt community
> and me of course would appreciate your help very much!

Still, try this:

Upload a PNG to X and/or FB. Copy the image, download the image from 
them after its up on their site. Do a file compare on it wrt your 
original source PNG. Are the exactly the same?