bwimage (version 1.3)

denseness_column: Denseness in column sections

Description

Calculate the denseness (proportion of black pixel in relation to the total number of pixels) for a given number of sections (n_sections). n_sections should be set as a number, in this situation denseness_column will break the original matrix in slices, and apply denseness_total function for each section. For instance, in a matrix of 1000x1000 if n_sections = 10, it will break to 10 sections of 1000x100 and analyze it. In other words, the sections will be the following sections of the original matrix [1:1000, 1:100] ,[ 1:1000,101:200] ,[ 1:1000,201:300] ,[ 1:1000,301:400] ,[ 1:1000,401:500] ,[ 1:1000,501:600] ,[ 1:1000,601:700] ,[ 1:1000,701:800] ,[ 1:1000,801:900] ,[ 1:1000,901:1000]. The default for parameter n_sections is "all", it will calculate denseness for each column of pixel. In other words, it will break the image in a number of section equal to the image pixel width.

Usage

denseness_column(imagematrix, n_sections = "all")

Arguments

imagematrix

The matrix to be analysed.

n_sections

Break the image in this number of columns.

Value

Denseness

Denseness of each column section.

Mean

Mean of column sections denseness.

SD

standard deviations of column sections denseness.

References

Zehm et al 2003 Multiparameter analysis of vertical vegetation structure based on digital image processing. Flora-Morphology, Distribution, Functional Ecology of Plants, 198: 142-160.

See Also

denseness_total threshold_color

Examples

# NOT RUN {
# First, get a matrix from your image. Here an example of a bush image is used.
bush<-system.file("extdata/bush.JPG",package ="bwimage")
bush_imagematrix<-threshold_color(bush,  "jpeg",  "proportional", compress_rate = 0.1)

# Calculate vegetation denseness in 20 column sections
denseness_column(bush_imagematrix,20)
# }