Which Dct Algorithm is used ?

Hello,

Can anyone tell me that which algo is used in this dct watermarking code or anyone who already used that code? Here is the link

https://nl.mathworks.com/matlabcentral/fileexchange/46866-watermark-dct

Thanks in advance!

Answer 1

[Walter Roberson]

https://www.mathworks.com/help/images/ref/dct2.html#d117e44015 describes the Discrete Cosine Transfer

dct2 does dct(), transposes the array, and does dct() again.

dct() that is invoked is a private function, not the public dct from the signal processing toolbox. However, the two use the same internal structure; fft() and multiply by weights.

[marie lasz]

Thanks for your response and I know that watermarking is performed here in dct domain but I don't know the complete algorithm? Or which research paper is followed?