VeloxRaster_col2im: col2im

In velox: Fast Raster Manipulation and Extraction

Description

Assigns values to a VeloxRaster band from a matrix of flattened image patches. Patch frames, as specified by rowframe and rowframe, are not assigned. This function is intended to be used with mat matrices constructed with the im2col function.

Arguments

mat	The matrix of flattened image patches.
wrow	Patch size in the y dimension.
wcol	Patch size in the x dimension.
band	The band to be assigned.
rowframe	A non-negative integer specifying the size of the frame around the image patches in the y dimension.
colframe	A non-negative integer specifying the size of the frame around the image patches in the x dimension.
rowstride	A positive integer denoting the stride between extracted patches in the y dimension.
colstride	A positive integer denoting the stride between extracted patches in the x dimension.

Value

Void.

Examples

## Make VeloxRaster
mat <- matrix(1:100, 10, 10)
vx <- velox(mat, extent=c(0,1,0,1), res=c(0.1,0.1), crs="+proj=longlat +datum=WGS84 +no_defs")
## Apply im2col
patch.mat <- vx$im2col(wrow=2, wcol=2, band=1, padval=0,
                       rowframe=1, colframe=1, rowstride=2, colstride=2)
## Apply col2im
vx$col2im(mat=patch.mat, wrow=2, wcol=2, band=1, rowframe=1, colframe=1, rowstride=2, colstride=2)
isTRUE(all.equal(mat, vx$as.matrix()))

velox documentation built on May 2, 2019, 6:01 a.m.