rgdal (version 0.3-7)

getPixmapGDAL: Read GDAL datasets as pixmapGrey or pixmapRGB objects

Description

A wrapper function for getRasterData() to insert the retrieved data into pixmap objects; only implemented now for greyscale and RGB data.

Usage

getPixmapGDAL(dataset, col=NULL, band = NULL, offset = c(0, 0), region.dim = dim(dataset), output.dim = region.dim, interleave = c(0, 0), stretch.bands = TRUE, as.is = FALSE)

Arguments

dataset

An object inheriting from class 'GDALReadOnlyDataset'

col

a vector of colours or a colour function such as rainbow

band

The band number (1-based) to read from

offset

Number of rows and columns from the origin (usually the upper left corner) to begin reading from

region.dim

The number of rows and columns to read from the dataset

output.dim

Number of rows and columns in the output data; if smaller than region.dim the data will be subsampled

interleave

Element and row stride while reading data; rarely needed

stretch.bands

if TRUE, stretch 3-band RGB images

as.is

If false, scale the data to its natural units; if the case of thematic data, return the data as factors

Value

• For single band data, returns a "pixmapGrey" object, for three band data, a "pixmapRGB" object.

See Also

GDALRasterBand-class

Examples

logo <- system.file("pictures/logo.jpg", package="rgdal")[1]
x <- new("GDALReadOnlyDataset", logo)
xGrey <- getPixmapGDAL(x)
xGrey
plot(xGrey)
xCm <- getPixmapGDAL(x, col=cm.colors)
xCm
plot(xCm)
GDAL.close(x)
Rlogo <- system.file("pictures/Rlogo.jpg", package="rgdal")[1]
y <- new("GDALReadOnlyDataset", Rlogo)
yRGB <- getPixmapGDAL(y)
yRGB
plot(yRGB)
GDAL.close(y)