Sky image features for Folsom, CA (lat=38.642N, lon=121.148W)

This file contains features derived from sky images obtained for Folsom, CA (lat=38.642N, lon=121.148W).
The file is in comma-separated values format.

The file has 16 columns. The first column is the timestamp in UTC in the format yyyy-mm-dd HH:MM:SS. This is the time when the image was captured.

The other 15 columns list values for OPERATOR(ImageData), where OPERATOR can be:

1. AVG: the average of the sky image pixels
2. STD: the standard deviation
3. ENT: the entropy

The ImageData can be:

1. R: the red color channel
2. G: the green color channel
3. B: the blue color channel
4. RB: the Red-to-Blue ratio R/B
5. NRB: the normalized Red-to-Blue ratio (R-B)/(R+B)