PhenoCam IR ROI Image Statistics File Format

An example IR ROI statistics file is below (for display purposes the lines have been broken with a '\' character):

#
# ROI IR statistics timeseries for alligatorriver
#
# Site: alligatorriver
# Veg Type: DB
# ROI ID Number: 1000
# Lat: 35.7879
# Lon: -75.9038
# Elev: 1
# UTC Offset: -5
# Resize Flag: False
# Version: 1
# Creation Date: 2021-03-23
# Creation Time: 15:15:26
# Update Date: 2021-10-01
# Update Time: 10:00:14
#
date,local_std_time,doy,filename,solar_elev,exposure,awbflag,mask_index,ir_mean,ir_std,\
ir_5_qtl,ir_10_qtl,ir_25_qtl,ir_50_qtl,ir_75_qtl,ir_90_qtl,ir_95_qtl
2012-05-06,07:30:32,127,alligatorriver_IR_2012_05_06_073032.jpg,27.85044,67,NA,1,96.99310,20.50304,\
61,70,84,99,111,122,128
2012-05-06,08:00:31,127,alligatorriver_IR_2012_05_06_080031.jpg,33.92559,40,NA,1,99.91418,21.25791,\
62,72,87,101,114,126,132
2012-05-06,08:30:31,127,alligatorriver_IR_2012_05_06_083031.jpg,39.97727,18,NA,1,96.99281,25.15680,\
57,67,81,96,112,130,141
2012-05-06,09:00:31,127,alligatorriver_IR_2012_05_06_090031.jpg,45.95232,14,NA,1,102.88782,22.98598,
62,73,89,104,119,131,138

Comments lines at the beginning of the file are preceeded with '# ' and include some basic site metadata along with creation and update dates and times.  (The long lines have been broken up here with a '\' character for display only.)

 

The columns in the file are described below:

  • date: local date for image
  • local_std_time: local standard time
  • doy: day of year
  • filename: filename
  • solar_elev: solar elevation angle
  • exposure: exposure - if available
  • awbflag: auto-white-balance flag - 0 if AWB disabled, 1 if AWB enabled
  • mask_index: index into mask list
  • ir_mean: mean digital number (DN) over the ROI
  • ir_std: standard deviation of DN over the ROI
  • ir_5_qtl,ir_10_qtl,ir_25_qtl,ir_50_qtl,ir_75_qtl,ir_90_qtl,ir_95_qtl: the 5,10,...,90,95 quantile values of the DN values over the ROI
 

As with the RGB/color images there are 3 bands in the images. For the IR images all three bands have the same value so the images appear as gray-scale or black and white images (except for the image overlay with the date, time, etc.). For calculating the statistics the first (red) band was used assuming all three bands have the same value.