MSU Brightness Independent PSNR (BI-PSNR)

Common idea

BI-PSNR metric is intended for measuring distortions in video taking into account brightness shifts.

Change Log

[!] — Known bug
[+] — New Feature
[*] — Other

Version 1.1
[*] Visualization bug fixed for non-stadard resolution video

Version 1.0
[+] First plugin release

Usage

BI-PSNR metric should be used when one of the sequences has any brightness transformation, which does not change within frame. Example of such transformation is uniform increasing of brightness of contrast for single frame of for all sequence. Such transformations prevent usage of standard metrics because of strong brightness difference between comparing frames. BI-PSNR algorithm calculates brightness transformation, which makes frames similar as possible and calculates standard PSNR and MSE metrics taking into account founded transformation.

Visualization

There are two part of visualization:

Example of
visualization
Example of visualization
Visualization of the same frame using standard
PSNR
Visualization of the same frame using standard PSNR

Plots

Plots of per-frame PSNR values after the found transformation are drawing after all calculations. Plots are entirely the same as standard per-frame PSNR

Plot's
example
Plot's example
Standard PSNR plot for the same
sequence
Standard PSNR plot for the same sequence

Algorithm

Table C[i,j] is filling for each frame: C[i,j] = { number of points in the same position, which have brightness i at the first sequence frame and j at the second sequence frame }

Next, for each i (brightness value from the first frame) we find corresponding brightness from the second sequence. Following formula is used to estimate distanse from arbitrary values of i and j:

One can note that this formula is sum of quadratic differences between all pixels of the first sequence with value i and all corresponding pixels from second sequence on the assumption that brightness was shifted to i-j.

When transformation was found, we can find MSE for the frame taking into account this transformation:

Download

Contacts

E-mail: video-measure@graphics.cs.msu.ru

10 May 2017
See Also
MSU 3D-video Quality Analysis. Report 11
MSU Video Quality Measurement Tool: Picture types
VQMT 13.1 Online help: List of all picture types available in VQMT and their aliases
MSU Video Quality Measurement Tool: Usage of VQMT metrics in CLI
VQMT 13.1 Online help: Description of VQMT metrics, their parameters and using in CLI
MSU Video Quality Measurement Tool: VQMT various lists and tables
VQMT 13.1 Online help: Information about VQMT visualization formats, read modes, etc...
MSU Video Quality Measurement Tool: Command-line help
VQMT 13.1 Online help: Information about all VQMT CLI options for Pro/Premium versions
MSU Video Quality Measurement Tool: Configuration description
VQMT 13.1 Online help: Description of the format of the VQMT configuration file
Site structure