Embedding visible watermark in color document.

I want to embed a visible watermark in a color document image in the blank space (black rectangle as shown in image) as shown in the attached image. I'll be very thankful to you.

With regards

Answer 1

[Shravan Kumar Vankaramoni]

Hi Balkar Singh,

Alpha blending method is used to watermark an image here

Watermarked_Image = Original_Image *alpha + (1-alpha)*watermark

Where alpha is the transparency parameter.

The following code demostrates this,

watermark = imread('saturn.png');
%Resize the watermark according to the area
modified = imresize(watermark,[64,64],'bilinear');
disp(size(modified));

original_image = imread('Marksheet1.png');

temp = zeros(size(original_image),'uint8');
[rows, cols, depth] = size(modified);
%Co-ordinnates to place the watermark
X = 21;
Y = 441;
temp(X:X+rows-1,Y:Y+cols-1,:) = modified;
temp(301:364,101:164,:) = modified;
temp(301:364,401:464,:) = modified;

alpha = 0.8;
watermarked_image = alpha * original_image  + (1-alpha)*temp;
imshow(watermarked_image);

[Balkar Singh]

@Shravan Kumar Vankaramoni thank you

But I got a error during the execution of the above code

watermarked_image = alpha * main + (1-alpha)*temp;

Undefined function or variable 'main'

what is main function here.

with regrads

[Shravan Kumar Vankaramoni]

The code has been corrected. You can try it now

[Balkar Singh]

Thank you Sir. It's working

With regards

[Balkar Singh]

@Shravan Kumar Vankaramoni Sir I have queries related to the above code

1. is it possible to implement the above code with the help of any transform like DWT.
2. How can I make the above code dynamic

With regards