Filters are coming to CSS so I guess it will be possible to show an image with hidden numbers (or words) and let the user pick a color filter that applied to th

Filters are coming to CSS so I guess it will be possible to show an image with hidden numbers (or words) and let the user pick a color filter that applied to the image will show the numbers and submit the color and the number to the server for verification. Like color blindness tests. How about that for a captcha?