On Fri, May 16, 2014 at 5:42 PM, Rik Cabanier <caban...@gmail.com> wrote:
> > Is the Web page not composited in sRGB? If so, it seems the backing store > should be sRGB too. > > The web page is not composited in sRGB. It is composited in the output device's color space, which is often sRGB or close to sRGB, but not always. A notable significant exception is pre Snow Leopard Macs that use a gamma 1.8 transfer curve. By the way, sniffing the display color profile through getImageData is a known fingerprinting technique. This factor alone can be sufficient to fingerprint a user who has a calibrated monitor.