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Data Types and Representation

Part 1

When looking for my text, "This is some sample text", in the hex editor, I found it easily with the .txt as there were very few other bits. image

When opening the .pdf file, which as a formatted file has lots of control codes, I couldn't find the sample text. However, I expect it's in-between the stream and endstream points that the editor identified.

(Top of the file, showing the stream text)
image

(Bottom of the file, with endstream)
image

There are multiple instances of endstream, so I believe the document also has the font and size information encoded in it as well.

The search box changes options because certain queries like 10 could be hex, decimal, or the user might want it interpreted as text.
image
The program does ask you to prefix a specific hex value you're searching for with 0x. If you enter something that cannot represent another type of data, the program then assumes you're searching for text.
image

Part 2​

I belive the image was created with Photoshop on a Mac, as the file contains: Adobe Photoshop CS4 Macintosh2011:01:14 14:32:2
image

The hidden message would appear to be: you found the hidden words!
image

Part 3​

The largest 8-bit number is 255. The smallest (signed) 8-bit number is -128.

Part 4​

  • 8-bit integer = 1 character
  • 16-bit integer = 2 characters
  • 24-bit integer = 3 characters
  • 32-bit integer = 4 characters
  • 64-bit integer = ..... 8 characters?