About mimic human visual response

Dear friends,

I am new to radiance. I have a some question about mimicking human visual response.

I have read part of the book "Rendering with Radiance", and it said that the mechamism of human eye to
adapt outside world has not been very well understood. So I wonder if anyone can give me some information
on the recent development in this area, to what extent it has been understood nowadays? Are there any websites or books I can refer to?

I noticed that now the digital cameras can perform auto white balance, and auto exposure, do they also
mimic the human eye response? I mean do they compress the dynamic range?

One more question is that I tried to use pcond program, I found that the option of -h and -e could not work together, I mean I can not mimic the human eye response and also adjust the exposure, did I made some mistakes?

Best wishes.

Yours,
Huang

Hello Huang,

From: "Huangwx@Kyoto Univ." <[email protected]>
Date: April 12, 2007 11:54:38 PM PDT

Dear friends,

I am new to radiance. I have a some question about mimicking human visual response.

I have read part of the book "Rendering with Radiance", and it said that the mechamism of human eye to
adapt outside world has not been very well understood. So I wonder if anyone can give me some information
on the recent development in this area, to what extent it has been understood nowadays? Are there any websites or books I can refer to?

There are a number of good papers, and some books as well. Do a search on "color appearance models" and the work of Marc Fairchild at RIT, James Ferwerda at Cornell Univ., and Sumanta Pattanaik at UCF. Some of this work has appeared at SIGGRAPH, and Pattanaik et al. from 1998 has a nice introduction to the many considerations of modeling human vision.

The pcond algorithm was described in a 1997 paper in IEEE TVCG:

  http://radsite.lbl.gov/radiance/papers/lbnl39882/tonemap.pdf

I noticed that now the digital cameras can perform auto white balance, and auto exposure, do they also
mimic the human eye response? I mean do they compress the dynamic range?

No, in fact most cameras increase contrast and color saturation in order to give images more "punch." This is the opposite of dynamic range compression.

One more question is that I tried to use pcond program, I found that the option of -h and -e could not work together, I mean I can not mimic the human eye response and also adjust the exposure, did I made some mistakes?

The -e option uses a linear exposure setting, which doesn't allow for dynamic range compression. That is why it doesn't work together with the -h option.

Hope this helps.
-Greg