Which is recommended for speed, dynamic desaturation or double images?

I would love to hear performance recommendation regarding image desaturation. I want to have an animation from desaturated to saturated image, and vice versa. So far I manage to use a jquery plugin to animate them on the fly. But just wonder about the performance implication with hundred of thumbnails on a page. Which do you recommend for better speed? Jquery or two static images with simpler animation?

UPDATE: FYI, apa开发者_如何学运维rt from 20 preloaded images, the rest are loaded via ajax like google infinite scroll

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If the animation is simply from desaturated to saturated, or vice-versa, layer one over the other and animate the opacity causing the top to fade in or out. The transition will be the same, if not better, with only 2 images needed, not 20.