Convert an image to grayscale in HTML/CSS

Question

Is there a simple way to display a color bitmap in grayscale with just HTML/CSS?

It doesn\'t need to be IE-compatible (and I imagine it won\'t be) -- if

Answer 1

Just got the same problem today. I've initially used SalmanPK solution but found out that effect differs between FF and other browsers. That's because conversion matrix works on lightness only not luminosity like filters in Chrome/IE . To my surprise I've found out that alternative and simpler solution in SVG also works in FF4+ and produces better results:

With css:

img {
    filter: url(filters.svg#desaturate); /* Firefox 3.5+ */
    filter: gray; /* IE6-9 */
    -webkit-filter: grayscale(1); /* Google Chrome & Safari 6+ */
}

One more caveat is that IE10 doesn't support "filter: gray:" in standards compliant mode anymore, so needs compatibility mode switch in headers to work: