Hi All,
 
I have a greyscale image that I am reading in through RGDAL and placing in a
pixmap object.
 
As an example use the logo.jpg file that comes with the RGDAL package:
 
#Read the file
logo <- system.file("pictures/logo.jpg", package="rgdal")[1]
x <- new("GDALReadOnlyDataset", logo)
 
#Create the pixmap object
xGrey <- getPixmapGDAL(x)
 
Now I would like to read individual pixel values and store them in a
separate vector. However I have not found a straight-forward way to do this.
 
I thought that something like:
 
x <- xGrey[1,1]
 
would return the pixel value, but it seems to return a pixmap object with
dimension 1x1 (i.e. only one pixel in size)
 
xGrey[1,1]
Pixmap image
  Type          : pixmapGrey 
  Size          : 1x1 
  Resolution    : 1x1 
  Bounding box  : 1 0 2 1
 
Any ideas on how to get the actual pixel value from a pixmap? (Note I could
output to an ascii file and then read the file back in as text - but not
nice!)
 
Thanks in advance
 
Tony
 
******************************************
Tony Gill - PhD Candidate
Centre for Remote Sensing & Spatial Information Science
School of Geography, Planning & Architecture
University of Queensland
Brisbane, Queensland, AUSTRALIA, 4072
Ph: 61-7-3365-7027
email: t.gill1@uq.edu.au

	[[alternative HTML version deleted]]


