Algorithm 1: Watermark embedding in Cover-Image

INPUT: Original Image “I”, Watermark, Secret Data

Step: 1 Take an input image “I” of size M × N.

Step: 2 Generate cover “C” of size M × 2N, by interleaving columns at alternate levels using ODNMI.

Step: 3 Take a fragile watermark sized (n × n).

Step: 4 Convert the watermark to a single row vector.

Step: 5 Take the secret data as a bitstream of a single-row vector and interleave the watermark bits in the data at regular intervals. In the proposed case one watermark bit is being interleaved after every 47 secret data bits. Apply AES-128 encryption to the secret data.

Step: 6 Covert all three-bit chunks into corresponding decimal equivalents by using binary to decimal conversion.

Step: 7 For Technique 1: Set three LSBs of all data pixels to zero, excluding seed pixels.

For Technique 2: Apply LDS to the resultant decimal equivalents.

Step: 8 Add the decimal equivalents to the corresponding data pixels.

Step: 9 Repeat Step 8 till all decimal equivalents of the secret data are embedded to obtain stego-image.

OUTPUT: Stego Image “S”