Enhance Contrast

A command line tool that takes a contrast enhanced screenshot of a given web page.

Usage

enhance-contrast url --width 1024 --height 768

The enhance-contrast generates two screenshots. The before.png (normal) and after.png (contrast enhanced). In the contrast enhanced screenshots, the contrast ratios between texts and backgrounds usually pass 4.5:1 (WCAG 2.0 Success Criterion 1.4.3 Contrast (Minimum)).

It also generates contrast.json which includes more detailed information.

Limitations

• Contrast calculations don't support images of texts
• Contrast calculations don't support background images (including CSS gradients)
• Contrast calculations are't accurate in some cases
• There are no plans to support full page screenshot
• This tool uses PhantomJS

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• Accessibility Developer Tools
• PhantomJS