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by mantrax 4467 days ago
You shouldn't trust that interpretation by Wolfram Alpha.

1. Distance. One obvious discrepancy is that the closer you look at the photo the less detailed it'll look. That's the opposite of how actual "vision" works. Even in dogs. You need to know how far away you should look at the photo, at what DPI screen in order for it to be even remotely representative for what it "feels" like for a dog to see.

2. Original image dpi. The second flaw is that if that image was a 600 dpi photo McNamara processed through the same filter, it wouldn't have lost nearly as much information percentage-wise, as a small image would.

3. What is "human vision"? The original image doesn't represent "human vision". It's a photo captured by a camera, resampled to a specific (small) resolution. Wolfram Alpha can't know how typical human vision "dpi" applies to that particular photo, because it needs to know a lot of information about the camera lens and sensor, which it doesn't know. So it can't approximate the dog version out of it by using relative human-to-dog metrics.

I love Wolfram & all their products.

However, sorry, but that "dog vision" image is not scientific. It's just bullshit.

3 comments

Harsh! The 2 color receptor part is accurate. And given that both photos are on your screen, and one is 20% less acute than the other, the approximation is fair.
Also, a lot of what we think of as vision happens in "software." A human looking at a human processes that information differently to a dog looking at a human.

Human's read faces, for example. To a human it seems that a lot more information is lost in the from the face part of the image than the hands area when you put it through that filter.

Excellent points, and why is the resulting picture larger than the original source image?

Sounds like more BS from this company (I don't have a ton of experience with their products but have followed their promotional materials quite frequently.)