To maybe expand on that, and make it a little more precise.
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Here are the histograms for the 2nd comparison pic in the zoomed comparison.
PS4 top, XB1 bottom.
(The big spike on the left side of the PS4 distribution is also present on the XB1 image, it's just sitting on the left border because I framed these images really poorly.)
The PS4 image contents look very similar to XB1's, except compressed within a range that looks suspiciously like the bounds for the "LDR" content in limited-range RGB. There's a
little bit of image content outside of that range; some of this is the "PS4" text on the image, the rest is pretty small and looks as though it's not much more than jpeg-related histogram bleeding.
Images 1 and 4 in the comparison have a similar thing going on.
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Images 3 and 5 are different. Image 3, the one with the snowy car, has this histogram, which looks more similar between PS4 and XB1:
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tl;dr DigitalFoundry probably captured some of the PS4 images from an RGB Limited source with an RGB Full receiver.