Learn R Programming

imager (version 0.15)

cimg.extract: Various shortcuts for extracting colour channels, frames, etc

Description

Various shortcuts for extracting colour channels, frames, etc

Extract one frame out of a 4D image/video

Usage

frame(im, index)

imcol(im, x)

imrow(im, y)

channel(im, ind)

R(im)

G(im)

B(im)

Arguments

im
an image
index
frame index
x
x coordinate of the row
y
y coordinate of the row
ind
channel index

Functions

  • frame: Extract frame
  • imcol: Extract a particular column from an image
  • imrow: Extract a particular row from an image
  • channel: Extract an image channel
  • R: Extract red channel
  • G: Extract green channel
  • B: Extract blue channel

Examples

Run this code
#Extract the red channel from the boats image, then the first row, plot
rw <- R(boats) %>% imrow(10)
plot(rw,type="l",xlab="x",ylab="Pixel value")
#Note that R(boats) returns an image
R(boats)
#while imrow returns a vector or a list
R(boats) %>% imrow(1) %>% str
imrow(boats,1) %>% str

Run the code above in your browser using DataLab