A Noble Algorithm to Secure Online Data Transmission One Hundred Percent at Zero Cost

Type of Encryption Algorithms Detectable by Bit Comparison Tools

• 1.

  LSB in GIF.

• 2.

  Steganographic Technique based on Difference Expansion method.

• 3.

  Hiding behind Corners.

• 4.

  Hiding Secret Message in Edges of the Image (RELSB).

• 5.

  Steganographic Technique based on Modulus Function and Pixel Value Differencing.

• 6.

  Data hiding method based on interpolation technique.

• 7.

  LSB principle of image steganography.

LSB in GIF

Palette based images, such as GIF images, are popular image file format commonly used on the Internet. GIF images are indexed images where the colors used in the image are stored in a palette or a color lookup table. GIF images can also be used for LSB steganography, although extra care should be taken. The main issue with the palette based approach is that if one changes the least significant bit of a pixel, it could result in an entirely different color since the index to the color palette gets modified. One possible solution to this problem is to sort the palette so that the color differences between consecutive colors are minimized. The main drawback of using GIF images in LSB steganography is that GIF images use to have a bit depth of 8 which means that information to be embedded is vey less as compared to other image formats. Second problem with GIF images is that these images are not secure to statistical as well as visual attacks, as the processing of palette processing to be done on the GIF images use to leave a clear signature on the image. This approach was dependent on the file format as well as the image itself, since a wrong choice of image could results in the message being visible (LSB in GIF, 2017).

Steganographic Technique Based on Difference Expansion Method

Difference Expansion (DE) is a more efficient and simple technique of data embedding used in digital images and is reversible in nature. In DE technique, one bit can be embedded into two pixels which are consecutive to each other. So it gives the maximum embedding capacity of 0.5 bpp. The main advantage of this technique was that it discovers extra storage space by exploring the redundancy in the image content. Both the payload capacity limit as well as the visual quality of embedded images of the DE method are the best along with a low computational complexity. The main problem with the difference expansion (DE) based reversible data hiding methods is that this technique is use to double differences between pixels in successive iteration. So this technique could not gain popularity. The DE is keen to statistical attacks as the level of distortions is high. DE based techniques use to have low payload capacity and could not be used for applications due to demand of high visual quality (Fridrich, Goljan & Du, 2001).