Rlogo: Rlogo jpeg image

Description Usage Format Examples

Description

Rlogo jpeg image data as imported by getRasterData in the rgdal package

Usage

1

Format

The format is: int [1:101, 1:77, 1:3] 255 255 255 255 255 255 255 255 255 255 ...

Examples

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## Not run: 
library(rgdal)
logo <- system.file("pictures/Rlogo.jpg", package="rgdal")[1]
x <- GDAL.open(logo)
gt = .Call('RGDAL_GetGeoTransform', x, PACKAGE="rgdal")
data <- getRasterData(x)
GDAL.close(x)

## End(Not run)
data()
d = dim()
cellsize = abs(c(gt[2],gt[6]))
cells.dim = c(d[1], d[2]) # c(d[2],d[1])
cellcentre.offset = c(x = gt[1] + 0.5 * cellsize[1], y = gt[4] - (d[2] - 0.5) * abs(cellsize[2]))
grid = GridTopology(cellcentre.offset, cellsize, cells.dim)
df = as.vector([,,1])
for (band in 2:d[3]) df = cbind(df, as.vector([,,band]))
df = as.data.frame(df)
names(df) = paste("band", 1:d[3], sep="")
 <- SpatialGridDataFrame(grid = grid, data = df)
summary()
spplot(, zcol=1:3, names.attr=c("red","green","blue"), 
	col.regions=grey(0:100/100),
	main="example of three-layer (RGB) raster image", as.table=TRUE)

sp documentation built on Jan. 13, 2021, 12:09 p.m.