mean.im
Mean and Median of Pixel Values in an Image
Calculates the mean or median of the pixel values in a pixel image.
Usage
## S3 method for class 'im'
## mean(x, trim=0, na.rm=TRUE, ...) ## S3 method for class 'im'
## median(x, na.rm=TRUE) [R < 3.4.0]
## median(x, na.rm=TRUE, ...) [R >= 3.4.0]
Arguments
- x
A pixel image (object of class
"im").- na.rm
Logical value indicating whether
NAvalues should be stripped before the computation proceeds.- trim
The fraction (0 to 0.5) of pixel values to be trimmed from each end of their range, before the mean is computed.
- …
Ignored.
Details
These functions calculate the mean and median
of the pixel values in the image x.
An object of class "im"
describes a pixel image. See im.object)
for details of this class.
The function mean.im is a method for the generic
function mean for the class "im".
Similarly median.im is a method for the generic
median.
If the image x is logical-valued, the mean value of x is
the fraction of pixels that have the value TRUE. The median is
not defined.
If the image x is factor-valued, then the mean of x
is the mean of the integer codes of the pixel values. The median is
are not defined.
Other mathematical operations on images are supported by
Math.im, Summary.im
and Complex.im.
Other information about an image can be obtained using
summary.im or quantile.im.
Value
A single number.
See Also
Math.im for other operations.
Examples
# NOT RUN {
X <- as.im(function(x,y) {x^2}, unit.square())
mean(X)
median(X)
mean(X, trim=0.05)
# }