Document containing a diagram on a background image. Sufficient contrast between foreground diagram and background image johannes.koch@fit.fraunhofer.de en Copyright BenToWeb 2004-2007 2005-08-11 validated

The test is intended to fail because the luminosity contrast ratio between diagram colour/page background colour is higher than 5, but between diagram colour/diagram background colour is lower than 5.

The formula to be used for calculating the luminosity contrast ratio can be found in http://www.w3.org/TR/2006/WD-WCAG20-20060427/appendixA.html#luminosity-contrastdef.

oneExpert

The foreground and background colours have not enough contrast.

The luminosity contrast ratio between diagram and page background is 6.12, between diagram colour and diagram background is 4.00.

This test case does not map to a WCAG 2.0 technique or failure.

The foreground and background colours have not enough contrast.

The WCAG WG hasn't provided threshold values for colour contrast yet.