/steg

Image steganography of PPM images to encode and decode messages in the red pixel field of the images using C.

Primary LanguageC

Image Steganography

Image steganography of PPM images to encode and decode messages in the red pixel field of the images using C.

Functions and roles

  • The getPPM function reads the PPM file and returns the structure (contents) of the ppm.
  • The showPPM function display the PPM image using printf calls, in exactly the syntax of a PPM file.
  • The encode function returns a copy of PPM image i with message text hidden in the red pixel field in successive pixels.
  • The decode function returns the message hidden in the red pixel values of an encoded PPM image by comparison with the red pixel values of the original PPM image.

Choice of data structures and algorithms

  • Used a 2D array to allocate memory for the pixels from the ppm.
  • Made use of a linked list using recursive struct "typedef struct Comment" to store the comments from the ppm.

Limitations

  • This program will not work if the ppm file contains comments that have more than 100 characters in one line.