Image quality assessment: Difference between revisions

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==Standard Images and Video==
==Standard Images and Video==
\(\DeclareMathOperator{\mean}{mean}\)
* MSE
* MSE
*:\[MSE = \mean((I_1 - I_2)^2)\]
* PSNR
* PSNR
*:\[PSNR=10\log_{10}(\frac{R^2}{MSE})\]
**where R^2 is the maximum fluctuation (e.g. 1.0 for [0-1] float images, 255 for uint8).
* SSIM
* SSIM



Revision as of 12:40, 27 August 2020

Methods for Image quality assessment

The standard metrics are mean-squared error, peak signal to noise ratio (psnr), and structural similarity (ssim).

Standard Images and Video

\(\DeclareMathOperator{\mean}{mean}\)

  • MSE
    \[MSE = \mean((I_1 - I_2)^2)\]
  • PSNR
    \[PSNR=10\log_{10}(\frac{R^2}{MSE})\]
    • where R^2 is the maximum fluctuation (e.g. 1.0 for [0-1] float images, 255 for uint8).
  • SSIM

Foveated Quality Assessment

  • Lee et al.[1] propose Foveated signal to noise ratio (FSNR) which measures the signal to noise ratio in a curvilinear space. However they do not provide the exact equations to compute the curvilienar space.

Spherical Quality Assessment

  • Yu et al.[2] propose Spherical PSNR (SPSNR) and WSPSNR.

References

  1. Sanghoon Lee, M.S. Pattichis, A.C. Bovik, (2002) Foveated video quality assessment IEEE Multimedia 2002.
  2. Matt Yu, Haricharan Lakshman, Bernd Girod (2015) A Framework to Evaluate Omnidirectional Video Coding Schemes ISMAR 2015.