24 Human visual metrics
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Last updated: November 26, 2025
25 Human visual metrics overview
Summary of what is to come.
25.1 Image quality metrics
I have links to both original measurements, modern measurements (Standard Spatial Observer), and many commercial versions of spatial metrics that are implemented in ISETCam. This section will describe those.
25.1.1 Classical
That single channel guy with his metric and formula. Repeated everywhere. Barten. SQRI.
Earlier single channel. Value of multiple channel metrics? Existence? S-CIELAB accounts for distance
SSIM and MS-SSIM
LPIP goes here because it is human judgments of image quality?
Pyramid from Beau? Multi-parameter
temporal MTF. Flicker.
I forked the Mantiuk github repository: The Mantiuk repository is here:. His metric goes here, I think. His code reads classic datasets. Maybe we include the data files in the book?
The surprising metric LPIPS
25.2 Human color metrics
CIELAB
S-CIELAB
Mark Fairchild contributions. Others?
25.3 Temporal metrics
temporal MTF metrics
25.4 Computer vision metrics for color?
They should be described elsewhere.
A lot of these might have been used in those directional cosine errors in Zheng’s dissertation