
	Where results make sense

Topic: PSNR

Related Topics

Image compression

Color image

MSE

In the News (Sun 6 Dec 09)

Northern Trust

Marvin Harrison

Peter Chernin

Gary Locke

Match Play

Penelope Cruz

Mickey Rourke

AR Rahman

Danny Boyle

Hugh Jackman

	PSNR Checker - Информация - CODEC.RU
		На практике видео изображение со значениями PSNR порядка 40-43 dB и выше является изображением высокого качества, в то время как значения порядка 30 dB и ниже характеризуют изображение плохого качества.
		Процедура перевода из RGB в YUV является линейной и обратимой для реальных значений цветности, то есть при обратном восстановлении сигнала RGB из YUV потери будут отсутствовать (PSNR равно бесконечности).
		Значение PSNR, вычисляемое программой, включает оценку всех промежуточных этапов кодирования, рассмотренных выше: преобразование RGB-24 в YUV, пространственное изменение разрешения цветности (UV) в драйвере, кодирование YUV-компонент, обратную процедуру передискретизации цветности и обратное преобразование YUV в RGB-24.
	www.codec.ru /information/psnr_checker.html (829 words)

	Peak signal-to-noise ratio - Wikipedia, the free encyclopedia
		The phrase peak signal-to-noise ratio, often abbreviated PSNR, is an engineering term for the ratio between the maximum possible power of a signal and the power of corrupting noise that affects the fidelity of its representation.
		The PSNR is most commonly used as a measure of quality of reconstruction in image compression etc. It is most easily defined via the mean squared error (MSE) which for two m×n monochrome images I and K where one of the images is considered a noisy approximation of the other is defined as:
		For color images with three RGB values per pixel, the definition of PSNR is the same except the MSE is the sum over all squared value differences divided by image size and by three.
	en.wikipedia.org /wiki/PSNR (242 words)

	An Introduction to Image Compression
		The MSE is the cumulative squared error between the compressed and the original image, whereas PSNR is a measure of the peak error.
		A lower value for MSE means lesser error, and as seen from the inverse relation between the MSE and PSNR, this translates to a high value of PSNR.
		Logically, a higher value of PSNR is good because it means that the ratio of Signal to Noise is higher.
	www.debugmode.com /imagecmp (583 words)

	H263 (Site not responding. Last check: )
		* * * PSNR (Y,U,V) = (28.6079 dB, 35.6115 dB, 34.9177 dB)
		* * * PSNR (Y,U,V) = (31.9264 dB, 37.7402 dB, 37.3844 dB)
		* * * PSNR (Y,U,V) = (34.3965 dB, 39.6745 dB, 39.5600 dB)
	eeweb.poly.edu /~yao/VideobookSampleData/doc/sample/H263.htm (387 words)

	Eugenio Ballini's Home Page
		In this case the PSNR parameter shown is taken as the mean value of the PSNR values of the 3 RGB components of the image; this is valid for all the results of the next sections if not specified to the contrary.
		All the PSNR results obtained for the 5 images and their mean, for the 3 different compression methods at various compression ratios are also summarised in Table 6.8.
		In Figure 6.26 the seven different curves of the PSNR mean values at different bit rate are depicted; decreasing the area of the ROI rectangle there is a decrement of the bit rate values where the PSNR value begin to decrease, and consequently the values of bit rate used to obtain a similar PSNR value.
	digilander.libero.it /eugenioballini/eugtesiwavc6.html (3793 words)

	[No title] (Site not responding. Last check: )
		The PSNR of a given component is the ratio of the mean square difference of the component for the two images to the maximum mean square difference that can exist betwee any two images.
		The mean square difference of a component for two images is the mean square difference of the component value, comparing each pixel with the pixel in the same position of the other image.
		A luminance PSNR of 20 means the mean square difference of the luminances of the pixels is 100 times less than the maximum possible difference, i.e.
	web.mit.edu /windows-graphics/man/man1/pnmpsnr.1 (225 words)

	Encoding parameters
		MEncoder PSNR: 05a, 01a, 13a, 08a, 02a, 12a, 11a, 07a, 10a, 04a, 03a, 09a, 06a, 05b, 01b, 13b, 02b, 12b, 10b, 11b, 07b, 08b, 09b, 03b, 04b, 06b.
		ImageMagick PSNR: 05a, 01a, 13a, 14a, 08a, 02a, 12a, 07a, 11a, 04a, 10a, 03a, 09a, 06a, 05b, 01b, 13b, 14b, 02b, 10b, 12b, 07b, 11b, 08b, 04b, 09b, 03b, 06b.
		PSNR: 05a, 01a, 13a, 14a, 08a, 02a, 12a, 07a, 11a, 04a, 10a, 03a, 09a, 06a, 05b, 01b, 13b, 14b, 02b, 10b, 12b, 07b, 11b, 08b, 04b, 09b, 03b, 06b.
	hem.bredband.net /nicsey/MEncoder/mencoder.html (3737 words)

	Quality Analysis Methodology
		PSNR analysis uses a standard mathematical model to measure an objective difference between two images.
		PSNR was calculated using the first-captured image as the reference image, not the original 1920x1080 source image.
		Consequently the PSNR analysis uses the first-captured image as the reference for both codecs.
	cineform.com /technology/HDQualityAnalysis10bit/HDmethodology10bit.htm (625 words)

	Eugenio Ballini's Home Page
		In this tests we are interested in the values of the PSNR which are obtained for every image; it is also possible to have a little idea about a possible compression ratio associated with each of the 9 images.
		Our analysis of the result on the tests is begun with the values of the PSNR belonging to the Y component; in the Figure 5.7 a detail of the original image “Ima3” is shown and the same detail for the other 10 reconstructed images obtained at different thresholds.
		With the help of Table 5.8, in which there are the values of the PSNR for the Symlet 4 QMF for the 5 images, shown in Figure 4.5, and with the help of the Figure 5.9, in which the same values are diagrammed, it is possible to see the trend of the different curves.
	digilander.libero.it /eugenioballini/eugtesiwavc5.html (2002 words)

	TechOnLine - Performance Analysis for Objective Methods of Video Quality Assessment (Site not responding. Last check: )
		PSNR measures the fidelity (how close a sequence is similar to an original one).
		In addition, PSNR considers only the luminance component and neglects the chrominance component, which is important for human perception.
		PSNR valueof the respective processed sequences decreased as the quantization parameter value increased.
	www.techonline.com /community/ed_resource/feature_article/38742 (2235 words)

	imgdist.1
		For the calculation of SNR and PSNR, imgfile1 is considered to be the original signal; imgdist thus finds the variance of imgfile1 for use in the SNR calculation.
		For the calculation of PSNR, imgdist assumes that the peak-to-peak range of imgfile1 is 255.
		However, the PSNR is now nearly universally accepted as the log of the square of the maximum possible peak-to-peak range allowed by the pixels, a value that depends on the bit-depth of the image pixels and not the reference image itself.
	qccpack.sourceforge.net /Documentation/imgdist.1.html (647 words)

	Evaluation
		MPEG streaming: Peak Signal-to-Noise ratio (PSNR) is a standard metric used to measure the quality of the video images in a stream.
		For every image, we compute the PSNR value of the received image in comparison to the video image in the original MPEG stream.
		PSNR value mainly to show that OverQoS not only improves the quality of the stream in the average case but also the minimum quality of a stream.
	www.usenix.org /publications/library/proceedings/nsdi04/tech/full_papers/subramanianOver/subramanianOver_html/node16.html (678 words)

	MATLAB Central File Exchange - PSNR
		This function displays the PSNR (peak signal-to-noise ratio) between two images.
		A sample use is in the comparison between an original image and a coded/decoded image.
		Typical quoted PSNR figures are in the range +25 to +35dB.
	www.mathworks.com /matlabcentral/fileexchange/loadFile.do?objectId=135 (259 words)

	Computation of SNR and PSNR
		Assume we are given a source image f(i,j) that contains N by N pixels and a reconstructed image F(i,j) where F is reconstructed by decoding the encoded version of f(i,j).
		PSNR in decibels (dB) is computed by using
		The MPEG committee used an informal threshold of 0.5 dB PSNR to decide whether to incorporate a coding optimization because they believed that an improvement of that magnitude would be visible.
	bmrc.berkeley.edu /courseware/cs294/fall97/assignment/psnr.html (457 words)

	[No title] (Site not responding. Last check: )
		It is defined as % PSNR = 20 * log10(b/rms) % where b is the largest possible value of the signal % (typically 255 or 1), and rms is the root mean square % difference between two images.
		The PSNR is given in % decibel units (dB), which measure the ratio of the peak % signal and the difference between two images.
		An increase % of 20 dB corresponds to a ten-fold decrease in the rms % difference between two images.
	summa.physik.hu-berlin.de /~lmaher/PSNR.m (236 words)

	Measures of image quality (Site not responding. Last check: )
		The PSNR measure is also not ideal, but is in common use.
		PSNR is a good measure for comparing restoration results for the same image, but between-image comparisons of PSNR are meaningless.
		One image with 20 dB PSNR may look much better than another image with 30 dB PSNR.
	www.osl.iu.edu /~tveldhui/papers/MAScThesis/node18.html (205 words)

	Video-in-Video Data Hiding (Site not responding. Last check: )
		Figure 9 shows a diagram of the PSNR for the recovered signature video after being MPEG coded/decoded at bit rates of 1.5, 1.7, 2.0, 2.3, and 2.6 Mbps.
		PSNR 25.8 dB PSNR 31.8 dB PSNR 31.1 dB
		PSNR 34.9 dB PSNR 33.4 dB PSNR 35.2 dB
	web.mit.edu /dlane/www/files/hiding1.6.htm (3902 words)

	Junqing Chen's Homepage
		The PSNR (based on the MSE) is 33.3 dB for the SPIHT image and 29.4 for PIC image.
		However, if one holds the image at the intended viewing distance (approximately at arm's length), the ringing disappears, and all that remains visible is the blurring of the SPIHT image.
		In contrast, the perceptual PSNR provided by the PIC metric is 46.8 dB for the SPIHT image and 49.5 dB for the PIC image.
	commnet.ece.northwestern.edu /~jqchen/research.html (1527 words)

	Proof of Question for Today 3/19/02:
		For the output of decoder 1, the PSNR is 33.6303; for decoder 2, it is 34.4895.
		Comparing the file size with the SDC with the same PSNR, SDC has only 22056bytes.
		PSNR of output of decoder 0 is 34.6801, which is equivalent to the PSNR of 4 bits quantizer.
	www.ee.umd.edu /~gmsu/ENEE739M/assign_3/ProofQfT031902.htm (938 words)

	michael stromberg » Quick JPEG and Image Resize Comparison
		I put together a small C# program to allow me to compare two images of similar size and calculate the PSNR and root mean squared error (RMSE) for each color plane and for a putative luminance (Y) plane based on the CCIR 601 luminance equation.
		Apparently the MPEG committee has informally considered a difference of 0.5 dB PSNR to be observable.
		Therefore it is questionable whether you would notice the difference between a JPEG encoded in ImageMagick and Photoshop (0.38 dB) with this example.
	michael.ubiqgen.com /2005/03/21/quick-jpeg-and-image-resize-comparison (419 words)

	[No title] (Site not responding. Last check: )
		It has been pointed out to me that these tests are probably invalid because On2 calculated PSNR in RGP rather than YUV.
		On2 Corporation recently released the VP6 codec, along with some sample videos and PSNR graphs comparing it to WMV9.
		As I mentioned above, I cannot compare the actual visual quality; however, the graphs posted at On2 show only PSNR to demonstrate that VP6 performs better than WMV9, so that is the only dataset I can extend.
	fatooh.org /vp6-lavc (466 words)

	Web Programming & Digital Media - MSE, SNR and PSNR
		The actual value of the PSNR is not necessarily very meaningful.
		You can see in the MSE equation that it can't tell the difference between many small errors that add up to a certain amount and a few large errors that might add up to the same amount.
		In the assignment, while you may choose to display the SNR or PSNR, the latter is preferred.
	goanna.cs.rmit.edu.au /~ronvs/teaching/WebProgramming-DigitalMedia/ass2002s2/mse.html (569 words)

	Embedded Papers - Power Supply Noise Rejection and Fiber Optic Transceivers
		While this PSNR test methodology and related test limits will refer to small form factor (SFF) transceivers, it can be adapted to any fiber optic transceiver platform.
		Since there are no established PSNR tests for fiber optic transceivers, discussions on power supply noise issues are typically followed by contentious debates.
		Finally, a PSNR test methodology and test limits are presented.
	www.embeddedstar.com /technicalpapers/content/p/embedded1300.html (262 words)

	PSNR ?
		afterdawn.com / forums / dvd±r for advanced users / psnr ?
		ReMPEG2 (and I guess other encodes too)calculates the average PSNR.
		I know it's some kind of quality index, but I'm clueless about the values and what to expect from a "good compression".
	forums.afterdawn.com /thread_view.cfm/22283 (59 words)

	[Mp4-tech] A doubt in calculation of PSNR value for Video (Site not responding. Last check: )
		I will not include that infinite in average PSNR calculation or > alternatively replace it with an assumed upper limit (e.g.
		However, as JM and, if I recall correctly, other reference encoders use average PSNR, we're pretty much stuck with it.
		However, in typical cases average PSNR has very little difference from properly computed PSNR.
	lists.mpegif.org /pipermail/mp4-tech/2005-May/005423.html (196 words)

	seqdist.1 (Site not responding. Last check: )
		The options -mse, -snr, -psnr, and -mae indicate in which form the distortion should be expressed.
		For the calculation of SNR and PSNR, seqfile1 is considered the original signal; seqdist thus finds the variance of seqfile1 for use in the SNR calculation.
		For the calculation of PSNR, seqdist assumes that the peak-to-peak range of seqfile1 is 255 levels.
	qccpack.sourceforge.net /Documentation/seqdist.1.html (323 words)

	[No title]
		Although RMSE and PSNR are known to not always faithfully represent visual quality, it is the only established, well-known, objective measure that works reasonably well across a wide range of compression ratios.
		For images encoded with a Region of Interest (ROI) the RMSE, as well as the corresponding PSNR, are calculated both for the ROI and for the entire image.
		Compression efficiency results It is well known that the compression performance of an image codec is determined both by the statistical characteristics of the input IRLS image [3] and by the capability of the coding algorithm to explore these characteristics.
	www.fsb.hr /Qirt2002/abstract/30.doc (1790 words)

	Brightness Independent PSNR (BI-PSNR)
		BI-PSNR algorithm calculates brightness transformation, which makes frames similar as possible and calculates standard PSNR and MSE metrics taking into account founded transformation.
		Plots of per-frame PSNR values after the found transformation are drawing after all calculations.
		Implemented metrics short info: PSNR, Delta, MSAD, MSE, SSIM, VQM, MSU Blurring, MSU Blocking
	compression.ru /video/quality_measure/metric_plugins/bi-psnr_en.htm (564 words)

	Results (Site not responding. Last check: )
		In order to have similar PSNR amplitude, we consider the sphere as having an area of 1, and rescale the distortion accordingly.
		The second result is that, except for highly smooth functions, the PSNR is a linear function of BPV.
		The butterfly scheme is mostly useful to produce smooth-looking result (but it is not a very good interpolating scheme).
	nikopol0.alrj.org /fsw/RESULTS.html (323 words)

Try your search on: Qwika (all wikis)