I'm designing a website that displays commercial images and want to avoid people saving the image on their computer. I realise that any security measure like this can be defeated by a determined attacker. I'm just looking for approaches the make things harder - enough to deter a casual attacker.
One idea I had was to serve valid images, with the pixel data encrypted, e.g. each byte XORed with X. JavaScript in the page would decrypt this and render the original image in a <canvas> block.
Can anyone recommend a library that helps implement this or a similar scheme?
