PSNR: Difference between revisions
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[[File:PSNR_Eq2.png|x48px|<math>MSE(I,K) = \frac{1}{M} \cdot \sum_{j=0}^{width-1} \sum_{k=0}^{height-1} | I(j,k) - K(j,k) |^{2}</math>]] | [[File:PSNR_Eq2.png|x48px|<math>MSE(I,K) = \frac{1}{M} \cdot \sum_{j=0}^{width-1} \sum_{k=0}^{height-1} | I(j,k) - K(j,k) |^{2}</math>]] | ||
The double-{{Serif|Σ}} term states that {{Serif|(''j'',''k'')}} runs over all pixels | Where ''{{Serif|M}} ''is the number of pixels in a frame ({{Serif|''width''}} '''·''' {{Serif|''height''}}) | ||
The double-{{Serif|Σ}} term states that {{Serif|(''j'',''k'')}} runs over all the pixels, summing the square of the difference between reference image {{Serif|''I''}} and test image {{Serif|''K''}}. | |||
'''External Links''' | '''External Links''' | ||
Latest revision as of 20:30, 26 November 2015
PSNR stands for Peak Signal-to-Noise Ratio. It is used as a measure of video quality. It is expressed in decibels. It's defined as
where I is the reference image, K is the image under test, and MSE is the Mean Squared Error between the two:
Where M is the number of pixels in a frame (width · height)
The double-Σ term states that (j,k) runs over all the pixels, summing the square of the difference between reference image I and test image K.
External Links
- For more details see wikipedia:PSNR.
- See also, wikipedia:SSIM (Structural SIMilarity), another widely-used quality measure.
- See also, wikipedia:Video Quality for a discussion of the difficulties involved in trying to make an "objective" quality measurement.
