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YMT 549Lab 3(33 Points)

1 / Download Hex Workshop (hw32v601) / Location: Flash Drive
2 / Install Launch hw32v601 / Conduct regular installation of Hex Workshop and then launch the application.
3 / Checking HEX signature / Click the File menu and then click Open. Navigate to the folder and select the SampleImage1.jpg file
4 / Compare the initial hexadecimal characters to the ones listed below.
Note: During the process if you receive a warning message about bookmarks, ignore (cancel) it.
5 / Common graphic file extensions and file signatures. / File Extension  Description  Hex Signature
BMP  Windows Bitmap Image  42 4D xx xx
GIF  Graphics Interchange Format File47 49 46 38 39 61 xx xx
GIF  GIF87a  47 49 46 38 37 61 xx xx
GIF  GIF87b  Trailer: 00 3B xx xx
ICO  Windows Icon File  00 00 01 00 xx xx
JPEG, JPG  Compressed graphics file  FF D8 FF E0 xx xx
4A 46 49 46 00 xx xx
FF D8 FF E1 xx xx
45 78 69 66 00 xx xx
PNG  Portable Network Graphics File 89 50 4E 47 0D xx xx
TIFF, TIF  Tagged Image File Format  49 49 2A 00 xx xx
6 / Questions / 1-Did the file signature match with the SampleImage1.jpg?
2-Repeat the same analysis for the other three files (SampleImage2.bmp, SampleImage3.gif, and SampleImage4.unk). Which one’s extension is not matching with the HEX signature?
3-Write necessary DOS Shell command to change that incorrect file extension found in question #4.
7 / Download Gimp / Location: Blackboard
8 / Install Gimp / Regular Installation
9 / Running Gimp /
  1. Launch Gimp
  2. The main screen should look this way.

  1. Click File menu then click New, which will open a Create a New Image dialog box. Accept the defaults within this dialog box and click OK.
  2. Click the File menu and then click Open as Layers in this Untitled box.
  3. Navigate and select SampleImage2.bmp file.
  4. Click Open.
  5. Again on the menu bar of the Untitled box, click the File menu and then click Open as Layers. Navigate and select SampleImage1.jpg file and click Open.

10 / Questions / 4-Click the Layer menu, click Stack, and then click Lower Layer. Write what happens.
5-Click the Layer menu, click Stack, and then click Raise Layer. Write what happens.
  1. Still in the window, click File menu and then click Save As. The Save Image dialog box opens with Untitled in the name input area. Change the file name to LayeredImage1. If necessary, click the drop down menu for other folders and browse to change the folder where you have your image files. Now click Select File Type (By Extension), scroll down to the Photoshop image file type, select it and click Save.
  2. Do not close the screen. Repeat step H. This time save the file as JPEG image instead of a Photoshop image.
  3. When you click Save, a message appears that let you know JPEG files can’t handle layers. Click Export, and then click Save (OK) to save the file as a JPEG.
  4. Close the image window.
  5. Back in the original the GIMP window, click the File menu, click Open and select LayeredImage1.psd. A new window should open.
  6. Click the Layer menu, click Stack, and then click Raise Layer.

12 / Questions / 6-Write what happens. (Then close the file without saving it)
7-Again, back at The GIMP box, click the File menu, click Open, and select LayeredImage1.jpg. Repeat step M, if possible. Explain what has happened?
13 / Download Steganography tool / Location: Flash Drive
14 / Install and Launch Steganography / Install the Steganography.exe application while accepting all defaults. If the Steganography application does not open, go to Start/All Programs/Steganography to open the application
15 / Hiding a Message /
  1. On the left side of the Steganography application, click on the folder button next to “HIDE Step 1: Select a carrier file”
  2. Browse and select SampleImage1.jpg picture file. Click Open
  3. Note the size of the file in the Steganography application
  4. In Steganography, click on the Add button, choose the New Message option, and click Next
  5. In the Add Instant Message window, type in a Subject line and a “secret message.” Click OK
  6. Click the Hide button to hide your secret message in the Carrier file (click OK to bypass the password option)
  7. When the Save As window opens, save your altered picture to afolder. Change the filename to “After Message Added”

16 / Question / 8- Go to the folder where you saved “After Message Added” file. Double click to openit. Can you tell any difference between it and your SampleImage1.jpg file?
17 / Retrieving Hidden Message /
  1. On the right side of the Steganography application, click on the folder button next to “UNHIDE Step 1: Specify a carrier file”
  2. Browse to the folder where you stored file and select the After message Added picture (carrier) file. Click Open

18 / Question / 9- Note the size of file in the Steganography application. Is the file size larger than the “original” file? Why/Why not?
19 / Retrieving Hidden Message (cont…) /
  1. Click the “Unhide” button
  2. Double-click on the message in the list to read the secret message.