Groups > comp.os.linux.advocacy > #465819

Re: Another Crypto Programming Challenge

From	owl <owl@rooftop.invalid>
Newsgroups	comp.os.linux.advocacy
Subject	Re: Another Crypto Programming Challenge
Date	2018-09-04 13:59 +0000
Organization	O.W.L.
Message-ID	<s9b0030aga.ay@rooftop.invalid> (permalink)
References	<141b6d57-9a26-4315-9817-1ff67b98ae19@googlegroups.com>

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fr314159@gmail.com wrote:
> Although the first crypto challenge is not finished, here is
> another one.  I call it "hiding in plain sight."
> 
> The lowest order bit of an image file is not essential for the
> faithfulness of the image data.  Therefore, a message can be inserted,
> bit by bit, into the lowest order bits of an image.
> 
> Create a program that will insert the bits of a message into
> the lowest order bit of a 8-bit per channel TIFF image.  The
> TIFF image is then losslessly compressed using LZW compression.
> 
> The program should also decompress and extract the message.
> 
> The TIFF file can be grayscale, i.e. only one 8-bit channel.
> 
> A color TIFF file (8-bit RGB) can also be used but only the
> B, or blue, channel shall contain the message.  Why?  Give an answer.
> 
> A b/w TIFF is no allowed.  Why?  Give an answer.
> 
> So c'mon.  Get moving.  Fast!
> 
> ************* Warning **************
> 
> Don't attempt this with Microshit Winblows.  There are no NATIVE TIFF
> libraries.  That's because the MS OS is pure junk.
> 
> But everything is available in a stock GNU/Linux system.
> 

steghide(1)                 General Commands Manual                steghide(1)

NAME
       steghide - a steganography program

SYNOPSIS
       steghide command [ arguments ]

Thread

Another Crypto Programming Challenge fr314159@gmail.com - 2018-09-04 06:45 -0700
  Re: Another Crypto Programming Challenge owl <owl@rooftop.invalid> - 2018-09-04 13:59 +0000
    Re: Another Crypto Programming Challenge fr314159@gmail.com - 2018-09-04 07:25 -0700
      Re: Another Crypto Programming Challenge owl <owl@rooftop.invalid> - 2018-09-04 15:05 +0000
        Re: Another Crypto Programming Challenge fr314159@gmail.com - 2018-09-04 08:30 -0700
          Re: Another Crypto Programming Challenge Steve Carroll <fretwizzer@gmail.com> - 2018-09-04 08:47 -0700
            Re: Another Crypto Programming Challenge Steve Carroll <fretwizzer@gmail.com> - 2018-09-04 09:00 -0700
              Re: Another Crypto Programming Challenge owl <owl@rooftop.invalid> - 2018-09-04 16:21 +0000
                Re: Another Crypto Programming Challenge Steve Carroll <fretwizzer@gmail.com> - 2018-09-04 09:26 -0700
                Re: Another Crypto Programming Challenge Steve Carroll <frelwizzen@gmail.com> - 2018-09-05 02:44 -0700
                Re: Another Crypto Programming Challenge fr314159@gmail.com - 2018-09-04 09:58 -0700
                Re: Another Crypto Programming Challenge Steve Carroll <frelwizzen@gmail.com> - 2018-09-04 10:37 -0700
                Re: Another Crypto Programming Challenge Steve Carroll <frelwizzen@gmail.com> - 2018-09-05 05:06 -0700
                Re: Another Crypto Programming Challenge owl <owl@rooftop.invalid> - 2018-09-05 16:37 +0000
                Re: Another Crypto Programming Challenge Steve Carroll <fretwizzer@gmail.com> - 2018-09-05 10:03 -0700
                Re: Another Crypto Programming Challenge fr314159@gmail.com - 2018-09-05 10:26 -0700
                Re: Another Crypto Programming Challenge Steve Carroll <fretwizzer@gmail.com> - 2018-09-05 09:43 -0700
                Re: Another Crypto Programming Challenge fr314159@gmail.com - 2018-09-05 10:36 -0700
                Re: Another Crypto Programming Challenge Steve Carroll <fretwizzer@gmail.com> - 2018-09-05 10:45 -0700
                Re: Another Crypto Programming Challenge Steve Carroll <frelwizzen@gmail.com> - 2018-09-05 11:02 -0700
                Re: Another Crypto Programming Challenge fr314159@gmail.com - 2018-09-05 12:35 -0700
                Re: Another Crypto Programming Challenge Steve Carroll <frelwizzen@gmail.com> - 2018-09-05 12:52 -0700
                Re: Another Crypto Programming Challenge Steve Carroll <fretwizzer@gmail.com> - 2018-09-05 14:50 -0700
                Re: Another Crypto Programming Challenge Steve Carroll <frelwizzen@gmail.com> - 2018-09-05 15:13 -0700
                Re: Another Crypto Programming Challenge "F. Russell" <fr@random.info> - 2018-09-05 22:34 +0000
                Re: Another Crypto Programming Challenge Steve Carroll <frelwizzen@gmail.com> - 2018-09-05 15:59 -0700
                Re: Another Crypto Programming Challenge Steve Carroll <frelwizzen@gmail.com> - 2018-09-06 00:33 -0700
                Re: Another Crypto Programming Challenge Steve Carroll <frelwizzen@gmail.com> - 2018-09-06 00:02 -0700
                Re: Another Crypto Programming Challenge Steve Carroll <fretwizzer@gmail.com> - 2018-09-06 09:35 -0700
                Re: Another Crypto Programming Challenge Steve Carroll <frelwizzen@gmail.com> - 2018-09-06 09:55 -0700
                Re: Another Crypto Programming Challenge chrisv <chrisv@nospam.invalid> - 2018-09-05 12:52 -0500
                Re: Another Crypto Programming Challenge Steve Carroll <frelwizzen@gmail.com> - 2018-09-05 11:18 -0700
                Re: Another Crypto Programming Challenge fr314159@gmail.com - 2018-09-05 11:23 -0700
                Re: Another Crypto Programming Challenge fr314159@gmail.com - 2018-09-05 11:38 -0700
                Re: Another Crypto Programming Challenge Steve Carroll <frelwizzen@gmail.com> - 2018-09-05 11:49 -0700
                Re: Another Crypto Programming Challenge Steve Carroll <frelwizzen@gmail.com> - 2018-09-05 12:04 -0700
                Re: Another Crypto Programming Challenge fr314159@gmail.com - 2018-09-05 11:48 -0700
                Re: Another Crypto Programming Challenge Snit <usenet@gallopinginsanity.com> - 2018-09-05 21:28 -0700
        Re: Another Crypto Programming Challenge Steve Carroll <frelwizzen@gmail.com> - 2018-09-04 08:47 -0700

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