DWT based Watermarking

hi i m doing project on watermarking ,i hv used fingerprint image and face image .i hv applied DWT on finger print thn divided detail cofficients into M*N size blocks and selected the high order bits of each block .and embed bits on specific positions.faceimage is used as watermark .nw i dnt know how to detect the watermark .plz help me in the detection process.reply as soon as possible.

[Walter Roberson]

You ask questions, then do not return to the topic for 3 months, and when you do, ask for a reply "as soon as possible". It is not clear why anyone should bother replying for another 3 or 6 months.

[mary]

i didnt find any helpful information from matlab centeral

i ws in very big problem .u r right bt u hv no idea of my problem

Answer 1

[Walter Roberson]

Detecting the watermark is going to depend upon the details of how you embedded it. Did you solve the embedding problem? If so, then you should probably update your previous question with the details of what you did to resolve it; then we would have something to go on.

[mary]

i m working on the detection.i m following the same steps as i have done in embedding bt i m confused .can u give me the general idea of detection.in detection im comparing the original content with the watermarked content .bt i am not sure of it.

[Walter Roberson]

In your previous question, you did not indicate how you ended up doing the embedding. If we do not know how you did the embedding, we cannot tell you how to do the detection.

Or is your question more general, along the lines of, "Suppose we have series of images, some of which have been watermarked by unknown means that may vary from image to image. How can we determine whether any given image has *some* watermark in it, including cases where we might not be able to determine exactly which bits are the watermark bits?"

[mary]

in the watermark embeding process i hv used hash function and i hv calculated positions .on that poistions watermark is embeded.then i hv recombined all the M*N blocks(previous question) and apply the IDWT .now in the detection process i m using the same procedure.bt i dnt know how to compare values .and what will be the output after detection?if i want to draw a graph or plot the detected watermark thn how it will work ?if u have any idea plz help me

Answer 2

[Peter Eze]

Explain your methodology or post sample codes