Rename hint.txt and hint.text to README.md

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+# Best use of cocoa - Bronze award
+
+Daniel Vik  
+<daniel@vik.cc>  
+<http://danielvik.com/>  
+
+
+## Judges' comments:
+### To build:
+
+    make vik
+
+This entry requires [Zlib](http://www.zlib.net/).
+
+### To run:
+
+#### Embed text (from file or command line):
+
+    ./vik e base.png filename > encodedimg.png
+    # or
+    ./vik e base.png SomeRandomText > encodedimg.png
+
+#### Extract the embedded text:
+
+    ./vik d encodedimg.png
+
+#### Embed a PNG into another
+
+    ./vik e base.png source.png > encodedimg.png
+
+#### Extract the embedded PNG:
+
+    ./vik d encodedimg.png > restored.png
+
+### Try:
+
+    ./vik e ioccc.png chocolate.png > chocolate-in-ioccc.png
+    ./vik e chocolate.png ioccc.png > ioccc-in-chocolate.png
+    ./vik d chocolate-in-ioccc.png > restored-chocolate.png
+    ./vik d ioccc-in-chocolate.png > restored-ioccc.png
+
+### Selected Judges Remarks:
+
+References to chocolate had no effect on judging this entry. We
+guarantee it.
+
+Can you discern hidden pieces of chocolate in chocolate-in-ioccc.png ?
+
+
+## Author's comments:
+Introduction
+------------
+
+This program is a  steganography application for embedding an image or text
+into another image as well as extracting  the embedded image  or text back.
+The program stores  the embedded  image or text in  the low bits of the RGB
+values.
+
+The program supports any 8 bit true color PNG images (RGB, RGBA, grayscale,
+and grayscale+alpha). The output image is always 8 bit RGB.  When embedding
+one image into another, the width and height needs to be the same.
+
+The program only updates the IDAT and IHDR chunks of the source image.  Any
+additional chunks are copied into the resulting image.
+
+### Bonus Extractor:
+
+For some reason the chocolate image seems to have some  special properties.
+Apart from  being quite big  and a little bit noisy,  it appears  that when
+embedded into  another image and extracted, the bitmap data is also a valid
+brain$#@$ program. It is of course possible to get the bitmap data from the
+extracted image, and run it through  any of the previous  winning brain$#@$
+interpreters, but I thought it would be easier to include an interpreter in
+the program  to avoid the hassle:
+
+    ./vik e ioccc.png chocolate.png > encodedimg.png
+    ./vik b encodedimg.png
+
+It is of course also possible  to embed a brain$#@$ program  as a text file
+(as explained above) and decode it, e.g.:
+
+    ./vik e ioccc.png .+[.+] > encodedimg.png
+    ./vik b encodedimg.png
+
+
+### Obfuscation
+
+I really wanted to keep  the program simple,  so instead of adding multiple
+macros or helper methods that can be confusing,  I placed all functionality
+in the main function. Main is called recursively and quite extensively, but
+it gives  the benefit  that all  invocations of  the function  has the same
+parameters, argv and argc.   This really helps readability, as a programmer
+doesn’t need to remember several variable or function names.   I also tried
+to reduce the number of keywords,  and the program only  has four for-loops
+followed by a single return statement.  There is a little bit of use of the
+question mark operator,   but this is really  there to keep  the program as
+simple as possible.
+
+
+### Portability
+
+The program is portable to most platforms that  have zlib  available.   The
+only system dependency is that the program relies on writing binary data to
+stdout.
+
+By default, Microsoft compilers adds carriage returns to new lines,  and to
+compile the program on this platform, the following line can be added after
+the  variable  declarations  in  the  main  declaration  in  order  to  run
+correctly:
+
+    _setmode(_fileno(stdout), 0x8000);
+
+
+### Limitations
+
+The program doesn’t have many error checks so passing in  invalid arguments
+or images of mismatching sizes, or unsupported pixel formats will cause the
+program to crash.
+
+
+### Extendability
+
+Since a lot of care was taken to keep the code simple,  it turned out to be
+quite easy to extend functionality. I did include a small brain$#@$ after I
+realized that the chocolate image had some interesting properties.
+
+But there  is more functionality  I added that didn’t  fit within  the size
+limits and could not remain included.   For example,  I added  a method  to
+format source code based on a PNG image.   So the format  of the program is
+actually done by the program itself.
+
+And to be honest,   the chocolate  image  did not have  a brain$#@$ program
+embedded to begin with.   I added functionality to the  program to  embed a
+brain$#@$  into a  PNG image and used it  to create the image provided with
+the entry.
+
+I also added a method to analyze PNG images,  to print the size and format,
+as well as the scan line filters.
+
+All these features  were quite easy to add,   much thanks to  the (actually
+pretty good) design of the code.
+
+--------------------------------------------------------------------------------
+<!--
+(c) Copyright 1984-2015, [Leo Broukhis, Simon Cooper, Landon Curt Noll][judges] - All rights reserved
+This work is licensed under a [Creative Commons Attribution-ShareAlike 3.0 Unported License][cc].
+
+[judges]: http://www.ioccc.org/judges.html
+[cc]: http://creativecommons.org/licenses/by-sa/3.0/
+-->