PSNR: Difference between revisions
From Avisynth wiki
Jump to navigationJump to search
m 1 revision |
Raffriff42 (talk | contribs) replace <math> with images generated @ Wikipedia |
||
| Line 1: | Line 1: | ||
PSNR is measured in decibels. It's defined as | PSNR is measured in decibels. It's defined as | ||
<math>PSNR(I,K) = 20 \cdot \log_{10}{(\frac{255}{\sqrt{MSE(I,K)}})}</math> | [[File:PSNR_Eq1.png|x40|<math>PSNR(I,K) = 20 \cdot \log_{10}{(\frac{255}{\sqrt{MSE(I,K)}})}</math>]] | ||
with | with | ||
<math>MSE(I,K) = \frac{1}{M} \cdot \sum_{j=0}^{width-1} \sum_{k=0}^{height-1} | [[File:PSNR_Eq2.png|x40|<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>]] | ||
where <tt>M</tt> = <tt>width</tt> | where <tt>M</tt> = <tt>width</tt> '''·''' <tt>height</tt> is the number of pixels in a frame and <tt>width</tt>, <tt>height</tt> are the width and height of the frame, respectively, in pixels. | ||
The double-sum term states that <tt>(j,k)</tt> runs over all pixels of the frame, summing the absolute value of the difference of I, K functions raised to the power of 2. | The double-sum term states that <tt>(j,k)</tt> runs over all pixels of the frame, summing the absolute value of the difference of I, K functions raised to the power of 2. | ||
Revision as of 17:01, 21 November 2015
PSNR is measured in decibels. It's defined as
with
where M = width · height is the number of pixels in a frame and width, height are the width and height of the frame, respectively, in pixels.
The double-sum term states that (j,k) runs over all pixels of the frame, summing the absolute value of the difference of I, K functions raised to the power of 2.
For more details see: http://en.wikipedia.org/wiki/PSNR .
