Browser Gamma Correction Test Page

Unlabelled PNGs on CSS Colors

This page was created in order to test the self-consistency of web browsers' gamma correction. In brief, if they gamma-correct CSS colors on non-sRGB systems (which is required, according to the CSS-1 specification), then they should also gamma-correct unlabelled images in the same way. Alternatively, if they don't gamma-correct CSS colors (which violates CSS, although it is allowed for HTML colors), then they should not gamma-correct unlabelled images, either. In the latter case, however, labelled images (such as PNGs with a gAMA, cHRM, sRGB or iCCP chunk) are unlikely to match the CSS colors across all platforms.

This version of the page uses unlabelled PNG images (i.e., no gamma info) and CSS colors for the backgrounds of the table cells. The images will be distinct from the cell backgrounds if the browser gamma-corrects only the CSS colors on a non-sRGB system (such as most Macs, SGIs and NeXT cubes). Most current browsers are ``lazy'' and ignore gamma correction altogether, however, in which case the edges of the images will be invisible.

ffffff

ffffcc

ffff99

ffff66

ffff33

ffff00