PSNR - Revision history

Raffriff42: tweak wording

2015-11-26T18:30:10Z

tweak wording

← Older revision		Revision as of 20:30, 26 November 2015
Line 6:		Line 6:
	[[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 ~~of the frame~~, summing the ~~squared absolute value~~ of the difference between reference image {{Serif\|''I''}} and test image {{Serif\|''K''}}.		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'''

Raffriff42: tweak wording

2015-11-26T18:00:46Z

tweak wording

← Older revision		Revision as of 20:00, 26 November 2015
Line 1:		Line 1:
	PSNR is ~~measured~~ in decibels. It's defined as		'''PSNR''' stands for '''P'''eak '''S'''ignal-to-'''N'''oise '''R'''atio. It is used as a measure of [http://en.wikipedia.org/wiki/Video_quality video quality]. It is expressed in [[wikipedia:Decibel\|decibels]]. It's defined as
			[[File:PSNR_Eq1.png\|x48px\|<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>]~~]		where ''{{Serif\|I}} ''is the reference image, ''{{Serif\|K}} ''is the image under test, and ''{{Serif\|MSE}} ''is the [http://en.wikipedia.org/wiki/Mean_squared_error Mean Squared Error] between the two:

	~~with~~		[[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~~\|~~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>]]~~		The double-{{Serif\|Σ}} term states that {{Serif\|(''j'',''k'')}} runs over all pixels of the frame, summing the squared absolute value of the difference between reference image {{Serif\|''I''}} and test image {{Serif\|''K''}}.

	~~where~~ ''~~{{Serif\|M}} = {{Serif\|width}}~~ '''~~·~~'~~'' {{Serif\|height}}'' is the number of pixels in a frame and {{Serif\|''width''}}~~, ~~{{Serif\|''height''}} are the width and height of the frame, respectively, in pixels~~.		'''External Links'''
			* For more details see [http://en.wikipedia.org/wiki/PSNR wikipedia:PSNR].
	~~The double-sum term states that {{Serif\|~~(~~''j'',''k''~~)~~}} runs over all pixels of the frame~~, ~~summing the absolute value of the difference of {{Serif\|''I, K''}} functions raised to the power of 2~~.		* See also, [http://en.wikipedia.org/wiki/Structural_similarity wikipedia:SSIM] (Structural SIMilarity), another widely-used quality measure.
			* See also, [http://en.wikipedia.org/wiki/Video_quality wikipedia:Video Quality] for a discussion of the difficulties involved in trying to make an "objective" quality measurement.
	~~For more details see:~~ http://en.wikipedia.org/wiki/~~PSNR~~ .

	[[Category:Glossary]]		[[Category:Glossary]]

Raffriff42: format inline math

2015-11-21T15:28:02Z

format inline math

← Older revision		Revision as of 17:28, 21 November 2015
Line 7:		Line 7:
	[[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>]]		[[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>~~ '''·''' ~~<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.		where ''{{Serif\|M}} = {{Serif\|width}} '''·''' {{Serif\|height}}'' is the number of pixels in a frame and {{Serif\|''width''}}, {{Serif\|''height''}} 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 {{Serif\|(''j'',''k'')}} runs over all pixels of the frame, summing the absolute value of the difference of {{Serif\|''I, K''}} functions raised to the power of 2.

	For more details see: http://en.wikipedia.org/wiki/PSNR .		For more details see: http://en.wikipedia.org/wiki/PSNR .

	[[Category:Glossary]]		[[Category:Glossary]]

Raffriff42: replace $with images generated @ Wikipedia$

2015-11-21T15:01:48Z

replace <math> with images generated @ Wikipedia

← Older revision		Revision as of 17:01, 21 November 2015
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} \| I(j,k) - K(j,k) \|^{2}</math>		[[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> ~~<math>\cdot</math>~~ <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.		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.

Admin: 1 revision

2013-05-09T21:34:06Z

1 revision

← Older revision	Revision as of 23:34, 9 May 2013
(No difference)

Wilbert: typo

2008-06-07T12:16:42Z

typo

New page

PSNR is measured in decibels. It's defined as

<math>PSNR(I,K) = 20 \cdot \log_{10}{(\frac{255}{\sqrt{MSE(I,K)}})}</math>

with

<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> <math>\cdot</math> <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.

For more details see: http://en.wikipedia.org/wiki/PSNR .

[[Category:Glossary]]

PSNR - Revision history

Raffriff42: tweak wording

Raffriff42: tweak wording

Raffriff42: format inline math

Raffriff42: replace with images generated @ Wikipedia

Admin: 1 revision

Wilbert: typo

Raffriff42: replace $with images generated @ Wikipedia$