LSB Based Color Image steganography Combined with Cryptography

We have to collect information in following topics and understand them.

1.Understanding of Image steganography
2.Understanding of LSB based steganography
3.Cryptography
4.peak signal-to-noise ratio (PSNR) and safety
5.performance evaluation of the Image steganography

Then compare the results mentioned in the paper.
            (results of PSNR and safety with traditional LSB based stenography technique)
            (results of PSNR and safety with stenography combined with cryptography technique)

Today we will concentrate on Topics 1,2 and 3.Please try to collect the information.

By tomorrow morning we can have a discussion for better understanding.

I have collected the following info, plz try to use it.


1. Understanding of Image steganography:

Steganography: how to hide certain information in another public information, and then to pass hidden information by transferring public information.

Steganography types:
1.Text
2.Image <= we concentrate more on image steganography.
3.feature


Image Compression:
Lossy (JPEG) and Lossless (BMP, GIF,..).
So BMP and GIF image formats are favorable for steganography.

2. Understanding of LSB based steganography:

LSB (Least Significant Bit): This is method for embedding data into cover image. The least significant bit of each pixel of an image is altered to a bit of a message that is to be hidden.

3. Cryptography

Hiding Secret information using secret key.

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