canvas has been tainted by cross-origin data in Chrome

[clawfire]

Error message on page loading in Chrome Version 34.0.1847.60 beta :

Uncaught SecurityError: Failed to execute 'getImageData' on 'CanvasRenderingContext2D': The canvas has been tainted by cross-origin data.

[clawfire]

Same on 34.0.1847.76 beta

[pketh]

also Safari 9