imager (version 0.20)

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

#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