This plug-in can easily convert every colored image (in an html page) into a B&W greyscale image. Read the plugin API on here http://gianlucaguarini.github.io/jQuery.BlackAndWhite/.
1 Include the plug into the page:
<script src="js/jQuery.BlackAndWhite.js"></script>
2 Set the image wrappers using the css:
.bwWrapper {
position:relative;
display:block;
}
3 Initialize the plug in:
$('.bwWrapper').BlackAndWhite({
hoverEffect : true, // default true
// set the path to BnWWorker.js for a superfast implementation
webworkerPath : false,
// to invert the hover effect
invertHoverEffect: false,
// this option works only on the modern browsers ( on IE lower than 9 it remains always 1)
intensity:1,
// this option enables/disables the attribute crossorigin=anonymous on image tags. Default true.
// please refer to https://github.com/GianlucaGuarini/jQuery.BlackAndWhite#important
crossOrigin: true,
speed: { //this property could also be just speed: value for both fadeIn and fadeOut
fadeIn: 200, // 200ms for fadeIn animations
fadeOut: 800 // 800ms for fadeOut animations
},
onImageReady:function(img) {
// this callback gets executed anytime an image is converted
}
});
the script works only for the images hosted on the same server in which the page is loaded!
If you are looking for a lightweight solution, you can use the following css instead, but it's not 100% crossbrowser:
img {
filter: url("data:image/svg+xml;utf8,<svg xmlns=\'http://www.w3.org/2000/svg\'><filter id=\'grayscale\'><feColorMatrix type=\'matrix\' values=\'0.3333 0.3333 0.3333 0 0 0.3333 0.3333 0.3333 0 0 0.3333 0.3333 0.3333 0 0 0 0 0 1 0\'/></filter></svg>#grayscale"); /* Firefox 10+, Firefox on Android */
filter: gray; /* IE6-9 */
-webkit-filter: grayscale(100%); /* Chrome 19+, Safari 6+, Safari 6+ iOS */
transition: 0.3s ease-in;
}
img:hover {
filter: url("data:image/svg+xml;utf8,<svg xmlns=\'http://www.w3.org/2000/svg\'><filter id=\'grayscale\'><feColorMatrix type=\'matrix\' values=\'1 0 0 0 0, 0 1 0 0 0, 0 0 1 0 0, 0 0 0 1 0\'/></filter></svg>#grayscale");
-webkit-filter: grayscale(0%);
}