Figure - PMC

Skip to main content

An official website of the United States government

Here's how you know

Here's how you know

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

View full-text article in PMC

. 2018 Oct 10;6:2101111. doi: 10.1109/JTEHM.2018.2875464

Search in PMC
Search in PubMed
View in NLM Catalog
Add to search

2168-2372 © 2018 IEEE. Translations and content mining are permitted for academic research only. Personal use is also permitted, but republication/redistribution requires IEEE permission. See http://www.ieee.org/publications_standards/publications/rights/index.html for more information.

PMC Copyright notice

FIGURE 4. — Mean frame brightness before and after CLAHE normalization. Overlaid distributions of the average image brightness before (gray) and after (blue) CLAHE confirm that the lighting conditions across images are more similar after equalization. Average brightness of a frame was measured by taking the mean of a frame’s value-layer intensity. Each histogram used the entire Subject 2 dataset ( = 625,127 frames).

Inline graphic — Mean frame brightness before and after CLAHE normalization. Overlaid distributions of the average image brightness before (gray) and after (blue) CLAHE confirm that the lighting conditions across images are more similar after equalization. Average brightness of a frame was measured by taking the mean of a frame’s value-layer intensity. Each histogram used the entire Subject 2 dataset ( = 625,127 frames).