4 ms·

Dynamic range is the ability to see things in both direct sunlight AND in dark shadows at the same time. You need to be able to see pedestrians that are both d

Dynamic range is the ability to see things in both direct sunlight AND in dark shadows at the same time. You need to be able to see pedestrians that are both directly lit by the sun and in the darkest shadows in the same frame of video. No long exposures, no multiple exposures with varying exposure -- a single frame. I don't know of any 24-32-bit per channel sensors, and that's what you'd need. We agree on vision processing. I thought I made it clear that it's a strong "backend" to vision (the brain or compute behind it) that makes it work so well, and that will be the case with good self-driving cars as well. I must have misstated something.

ajross 8y ago
You're fooling yourself if you think your eyes can do that. They can't. More to the point, your brain is fooling you, by synthesizing a perception of a reality, the same way it does to make you think the stuff in your peripheral vision is as sharp as the things in the middle. Vertebrate eyes don't have 24 bits of sensitivity, that's just insane. Rod cells are neurons, they either fire or they don't, can fire at most at about 10 Hz, and you have about a million of them at most across your whole field of vision. Do the math. What you say isn't even physically possible.
- naikrovek 8y ago
  You're correct that the brain fills in a lot that isn't there, making you think your vision is a lot better than it is. It doesn't change much, though, mostly it fills in gaps. 10Hz? Simply not true. Fighter pilots can identify aircraft shown on a screen for 1/250th of one second. Regular schmoes can see the difference between 30Hz and 60Hz video easily. I am not arguing about pixel count of a camera vs the center of vision of human eyes. I'm saying that... Nevermind. I've already said it several times and apparently you have a PhD in all things vision.
  - Robotbeat 8y ago
    Being able to recognize aircraft on a screen for 1/250th of a second just means the human eye/brain has persistence, not actual useful 250Hz bandwidth.
pedrocr 8y ago
> I don't know of any 24-32-bit per channel sensors, and that's what you'd need. Dynamic range doesn't require bit depth. You can have an 8 bit sensor with 20 stops of dynamic range. You'll lose color/luminance resolution of course but as long as 255 is capturing a light that's 2^20 times stronger than 0 that's 20 stops of dynamic range. But more than that theoretical point there are already sensors pushing well beyond what humans can do in terms of dynamic range. Apparently humans have a respectable 10 stops and sensors are already in the 15 to 20 stop range and pushing beyond it: https://www.eoshd.com/2014/11/new-sony-sensor-21-stops-dynamic-range-5120-native-iso-destined-high-speed-cinema-camera-smartphone/ https://www.eoshd.com/2014/11/new-sony-sensor-21-stops-dynam... To map it into 16bit values you can just use a curve to distribute the bit depth unevenly across the dynamic range. Older DSLRs did that to get perfectly usable images with just 10 bits per channel.

ajross 8y ago

You're fooling yourself if you think your eyes can do that. They can't. More to the point, your brain is fooling you, by synthesizing a perception of a reality, the same way it does to make you think the stuff in your peripheral vision is as sharp as the things in the middle. Vertebrate eyes don't have 24 bits of sensitivity, that's just insane. Rod cells are neurons, they either fire or they don't, can fire at most at about 10 Hz, and you have about a million of them at most across your whole field of vision. Do the math. What you say isn't even physically possible.

naikrovek 8y ago
You're correct that the brain fills in a lot that isn't there, making you think your vision is a lot better than it is. It doesn't change much, though, mostly it fills in gaps. 10Hz? Simply not true. Fighter pilots can identify aircraft shown on a screen for 1/250th of one second. Regular schmoes can see the difference between 30Hz and 60Hz video easily. I am not arguing about pixel count of a camera vs the center of vision of human eyes. I'm saying that... Nevermind. I've already said it several times and apparently you have a PhD in all things vision.
- Robotbeat 8y ago
  Being able to recognize aircraft on a screen for 1/250th of a second just means the human eye/brain has persistence, not actual useful 250Hz bandwidth.

pedrocr 8y ago

> I don't know of any 24-32-bit per channel sensors, and that's what you'd need. Dynamic range doesn't require bit depth. You can have an 8 bit sensor with 20 stops of dynamic range. You'll lose color/luminance resolution of course but as long as 255 is capturing a light that's 2^20 times stronger than 0 that's 20 stops of dynamic range. But more than that theoretical point there are already sensors pushing well beyond what humans can do in terms of dynamic range. Apparently humans have a respectable 10 stops and sensors are already in the 15 to 20 stop range and pushing beyond it: https://www.eoshd.com/2014/11/new-sony-sensor-21-stops-dynamic-range-5120-native-iso-destined-high-speed-cinema-camera-smartphone/ https://www.eoshd.com/2014/11/new-sony-sensor-21-stops-dynam... To map it into 16bit values you can just use a curve to distribute the bit depth unevenly across the dynamic range. Older DSLRs did that to get perfectly usable images with just 10 bits per channel.