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Comment by tomekowal | Hacker News Reader

I think that object recognition is hard because humans have much more data than computers. People see with two eyes which can focus on different distances, so our brain has 3D data to learn from. We later learn to recognise the same objects on pictures.

Computers usually start from flat pictures, and that trips the learning process.

I have zero data to back it up. Just my hunch :D

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So children that's blind on one eye take longer to learn to recognize objects?

Not necessarily longer but it would probably have an effect on precision.

No but they cannot see depth very well because they can't use stereoscopic vision (triangulate). However, there are other cues that are used to infer for depth such as covered edges(if one object partially covers another then it is closer to you), perspective (if two objects that you know are similar in size but one appears smaller then it is farther) etc.

A friend of mine who cannot see with one eye and yet he is a painter. One thing I know he cannot do is drive a car.

>> One thing I know he cannot do is drive a car.

You are allowed to drive a car if you only have one eye, though.

Besides - I don't really think I myself use the perception of depth from my stereo vision as much as I know that the cars on the road are all standard dimensions.

There's not so many objects on the road which have similar proportions of dimensions but are different in size so are easily mistaken.

You have enough distance information by simply observing the visible width of the car in front of you.

My friend thinks he isn't allowed and that's based on his knowledge. He might as well be wrong.

> One thing I know he cannot do is drive a car

That's specific to your friend, not true in general. Lots of people drive with only one functional eye. At the visual distances involved, the depth perception provided by stereoscopic vision doesn't matter much. Especially with all the relative motion. My dad has been driving successfully for 65 years with only one working eye.

To be honest I don't know whether he is allowed to drive or not, he thinks he isn't allowed and never pursued it.

There's a cutoff of a 20/40 on at least one eye (corrected with class A restriction)

I drove for many years with amblyopia, so I didn't have much stereo depth perception. It did cause problems with parallel parking.

All those other cues are present in images from cameras as well. The only one I can think of that typically aren't used much for computer vision is focus distance, but for objects far away I don't think that helps us much in object recognition since all of the object are in focus anyway.

There are no cues from parallax motion in a static image though.

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