flir_stats: Statistics from 'get_stats' for photo FLIR8565.jpg

In rasenior/ThermStats: Calculate statistics for thermal images

Statistics from get_stats for photo FLIR8565.jpg

Description

Results of running get_stats for photo FLIR8565.jpg. The image file is included in the package installation and can be located by: system.file("extdata/FLIR8565.jpg", package = "ThermStats").

Usage

flir_stats

Format

A list consisting of:

• df = A dataframe with one row for each pixel, and variables denoting: the pixel value (val); the original spatial location of the pixel (x and y); its patch classification (G_bin) into a hot (1), cold (-1) or no patch (0) according to the Z value (see spdep::localG); the unique ID of the patch in which the pixel fell; and the matrix ID (if applicable).

• patches = A SpatialPolygonsDataFrame of hot and cold patches. Hot patches have a value of 1, and cold patches a value of -1.

• pstats = A dataframe with patch statistics for hot patches and cold patches, respectively. See patch_stats for details of all the statistics returned.

Details

This data is primarily included to speed up build time of the package vignette (see browseVignettes("ThermStats")). If interested, you can reproduce flir_stats following the example below.

Examples

head(flir_stats$df)
flir_stats$pstats
plot_patches(df = flir_stats$df,
             patches = flir_stats$patches, 
             save_plot = FALSE, 
             print_plot = TRUE)
             
# Recreate flir_stats ------------------------------------------------------

# Define raw data
raw_dat <- flir_raw$raw_dat$`8565`
# Define camera calibration constants dataframe
camera_params <- flir_raw$camera_params
# Define metadata
metadata <- flir_metadata
# Create vector denoting the position of photo within metadata
photo_index <- match(8565, metadata$photo_no)
# Convert
flir_converted <- 
    Thermimage::raw2temp(
        raw = raw_dat,
        # Emissivity = mean of range in Scheffers et al. 2017
        E = mean(c(0.982,0.99)),
        # Object distance = hypotenuse of right triangle where 
        # vertical side is 1.3 m (breast height) & angle down is 45°
        OD = (sqrt(2))*1.3,
        # Apparent reflected temperature & atmospheric temperature =
        # atmospheric temperature measured in the field
        RTemp = metadata$atm_temp[photo_index],
        ATemp = metadata$atm_temp[photo_index],
        # Relative humidity = relative humidity measured in the field
        RH = metadata$rel_humidity[photo_index],
        # Calibration constants from 'batch_extract'
        PR1 = camera_params[,"PlanckR1"],
        PB = camera_params[,"PlanckB"],
        PF = camera_params[,"PlanckF"],
        PO = camera_params[,"PlanckO"],
        PR2 = camera_params[,"PlanckR2"])
        
# Get stats
flir_stats <-
    get_stats(
        # The temperature dataset
        img = flir_converted,
        # The ID of the dataset
        id = "8565",
        # Whether or not to calculate thermal connectivity
        calc_connectivity = FALSE,
        # Whether or not to identify hot and cold spots
        patches = TRUE,
        # The image projection (only relevant for geographic data)
        img_proj = NULL,
        # The image extent (only relevant for geographic data)
        img_extent = NULL, 
        # The data to return
        return_vals = c("df", # Temperature data as dataframe
                        "patches", # Patch outlines
                        "pstats"), # Patch statistics dataframe
        # The summary statistics of interest
        sum_stats = c("median", "SHDI", "perc_5", "perc_95"))

rasenior/ThermStats documentation built on Nov. 16, 2024, 5:34 p.m.