[WM]: PSNR in Watermarking technique which uses the DCT coefficients.

[=?big5?B?q9ikQChKaWFuIFlpKQ==?= <im943084@mail.cpu.edu.tw>]

Dear. Advancer =

 

My question is about the = PSNR(Peak Signal to Noise Ratio) value .

I wonder whether there is = the general range of PSNR value , especially in the Watermarking algorightm which = uses DCT transformation.

 

I know some DCT block-based = coefficient modified method, but I always get a PSNR value under 30db after even a = little coefficient modified.

 

I read some paper their experiment is in the range frome 30 to 40 depend on compression ratio, so I want to = know whether a PSNR range exits.

 

Thanks for your answering me.

 

Best Regards

 

 

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