pnm {e1071} | R Documentation |
read.pnm
reads a pnm file and loads the image into an
object of class pnm
, which is basically a
matrix (pbm, pgm) or a 3-dimensional arry with 3 matrices for red,
green and blue.
write.pgm
writes an object of class pnm
to a
pgm file. Generalizations for writing pbm and ppm files are yet to be
written.
plot.pnm
plots a pnm object using the command
image
. The only difference is that the element [1,1]
of
pnmobj
is plotted as the upper left corner (plain
image
would plot [1,1]
as the lower left corner.
channel.pnm
extracts a black-and-white picture corresponding to
one of the three color channels.
read.pnm(file) plot(pnmobj, xlab="", ylab="", axes=FALSE, ...) write.pgm(pnmobj, file="Rimage.pgm", forceplain=FALSE) channel.pnm(pnmobj, chan = "red")
pnmobj |
an object of class pnm |
file |
name of the pnm file |
forceplain |
If TRUE , an ASCII pgm file is written. Default
is to write a binary (raw) pgm file. |
chan |
Channel to extract (one of "red" , "green"
and "blue" ). |
read.pnm
returns an object of class pnm
. The maximum
value (of either grey or the red/green/blue channels) is stored as
attribute "maxval"
). The type (pbm, pgm or pnm) is stored as
attribute "type"
).
Friedrich Leisch