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MSU Noise Estimation Metric
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Common description

Metrics Noise Estimator is intended for calculation of noise level for each frame of video sequence.

Visualization                           

No.

Plots                           

By results of job of the metrics the plot of frame-accurate value of noise level is constructed. 
Final value of the metrics is average arithmetic of all frame-accurate values.

Algorithm

MAD
For each frame do HAAR wavelet decomposition. Than evaluate median of HH-component's absolute values.
Final value of the metrics is the normalized median.


Block-Based
Frames are tessellated into a number of 8x8 blocks. Standard deviations of intensity (measures of intensity
variation) are computed for all the blocks and sorted. The block with the smallest standard deviation has the least change
of intensity. The smaller the standard deviation, the smother the block. The intensity variation of a smooth block may be
due to noise, in which the standard deviation of the block is close to that of the Gaussian noise added. 
Normalized average arithmetic values of 30 % of all blocks with the least values grows is the final value of the metric.


Spatio-Temporal Gradients
For each frame is doing wavelet decomposition. computing temporal and spatial histograms. The initial estimation of 
noise level is defined by value at which temporal or spatial histogram achieves the maximal value. The decision of 
whether to use the spatial or temporal histogram is based on the deviation of the histogram from the Rayleigh distribution. 
Then this estimation is corrected, using Kolmogorov-Smirnoff test. The normalized corrected estimation is the final value 
of the metric.

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Plugin must be placed to \plugins folder in 
directory with the tool and have .vmp extension.
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(c) MSU Video Group 2003-2008, http://compression.ru/video/
This source code is property of MSU Graphics and Media Lab

This code may be distributed under LGPL
(see http://www.gnu.org/licenses/lgpl.html for more details).

E-mail: video-measure((at))compression.ru
Author: Kumok Boris
Webpage: http://compression.ru/video/quality_measure/metric_plugins/ne_en.htm