thr.check: Evaluate a range of threshold values for creating binary...
In ckenaley/trackter: Automated Kinematic Analysis of Image Data

Description Usage Arguments Details Value See Also Examples

Converts an image to grayscale, applies a user defined threshold range to segment the binary the image, and then plots segmented images that reflect 9 discrete values in the range.

1	thr.check(img, min = NULL, max = NULL, otsu = TRUE, plot.grid = TRUE)

`img`	character, a path to an image file.
`min`	numeric, the minimum threshold value (0-1).
`max`	numeric, the maximum threshold value (0-1).
`otsu`	logical, should the automatically determined threshold value be printed. See Details.
`plot.grid`	logical, should the grid of images be plotted.

Displays a grid of 9 images as an R raster graphic, each the result of 9 discrete values within the range describe by min and max. If both min and max are NULL, then the threshold range is defined by the default seq(0.1,0.9,.1). This function should help users refine threshold values for detecting ROIs with kin.search and kin.simple if automatic thresholding using Otsu's method is not satisfactory.

If 'otsu=TRUE', a single automated threshold value is returned using Otsu's method. See otsu.

kin.simple, kin.search, otsu

#access image in system
 y <-system.file("extdata/img", "sunfish_BCF.jpg", package = "trackter")

# default values
thr.check(y)

#custom values
thr.check(y,min=0.2,max=1.5)