Ok, thanks. I can try later today with Manifold System, which may be. I'm
not sure of other non-GDAL tools to double check TIFFs with. (ArcGIS 10 uses
GDAL but I don't know to what extent).
Is the output above what you expect, or what you get? That's what I get.
Sorry to be dim, but I don't see where you've specified what's actually
wrong (and I haven't explored enough to see if that's easy to determine from
the code).
That's a cunning use of formals() to change defaults for a function - a bit
radical for my taste, but I like it.
Cheers, Mike.
On Fri, Nov 5, 2010 at 11:00 AM, Oliver Soong
<osoon...@gmail.com<osoong%...@gmail.com>
> wrote:
> Here's an example:
>
>
>
>
> require(rgdal)
> formals(paste)$sep <- ""
>
> SP27GTIF <- readGDAL(
> system.file("pictures/SP27GTIF.TIF", package = "rgdal")[1],
> output.dim=c(100,100)
> )
> img_1bit_1band <- SP27GTIF
> img_1bit_1b...@data$band1 <- as.integer(sp27g...@data$band1 > 85)
> img_1bit_2band <- SP27GTIF
> img_1bit_2b...@data <- data.frame(
> band1 = img_1bit_1b...@data$band1,
> band2 = as.integer(sp27g...@data$band1 > 170)
> )
>
> for(img in c("img_1bit_1band", "img_1bit_2band")) {
> cat(paste("*** Correct Stats: ", img, "\n"))
> print(sapply(get(img)@data, table))
> for(compress in c("NONE", "DEFLATE", "LZW", "CCITTRLE",
> "CCITTFAX3", "CCITTFAX4")) {
> file <- paste(img, "_", compress, ".tif")
> writeGDAL(get(img), file, type = "Byte",
> options = c("NBITS=1", paste("COMPRESS=", compress)))
> cat(paste("Compression: ", compress, " from ", file, "\n"))
> reread <- readGDAL(file, silent = TRUE)
> print(sapply(rer...@data, table))
> }
> cat("\n")
> }
>
>
>
>
>
> The expected output is:
>
> *** Correct Stats: img_1bit_1band
> band1
> 0 3086
> 1 6914
> Compression: NONE from img_1bit_1band_NONE.tif
> band1
> 0 3086
> 1 6914
> Compression: DEFLATE from img_1bit_1band_DEFLATE.tif
> band1
> 0 3086
> 1 6914
> Compression: LZW from img_1bit_1band_LZW.tif
> band1
> 0 3086
> 1 6914
> Compression: CCITTRLE from img_1bit_1band_CCITTRLE.tif
> band1
> 0 3086
> 1 6914
> Compression: CCITTFAX3 from img_1bit_1band_CCITTFAX3.tif
> band1
> 0 3086
> 1 6914
> Compression: CCITTFAX4 from img_1bit_1band_CCITTFAX4.tif
> band1
> 0 3086
> 1 6914
>
> *** Correct Stats: img_1bit_2band
> band1 band2
> 0 3086 8353
> 1 6914 1647
> Compression: NONE from img_1bit_2band_NONE.tif
> band1 band2
> 0 3086 8353
> 1 6914 1647
> Compression: DEFLATE from img_1bit_2band_DEFLATE.tif
> band1 band2
> 0 3086 8353
> 1 6914 1647
> Compression: LZW from img_1bit_2band_LZW.tif
> band1 band2
> 0 3086 8353
> 1 6914 1647
> Compression: CCITTRLE from img_1bit_2band_CCITTRLE.tif
> band1 band2
> 0 6131 8783
> 1 3869 1217
> Compression: CCITTFAX3 from img_1bit_2band_CCITTFAX3.tif
> band1 band2
> 0 6131 8783
> 1 3869 1217
> Compression: CCITTFAX4 from img_1bit_2band_CCITTFAX4.tif
> band1 band2
> 0 6131 8783
> 1 3869 1217
>
>
>
> Everything looks fine except CCITT compression with 2 bands.
>
> I wasn't able to dig up Windows GDAL 1.7.1 binaries, and the 1.7.0
> binaries from FW_Tools seem to give similar behavior, although it's a
> little hard to check because neither ArcGIS nor ENVI seems to like any
> of the multi-band files.
>
--
Michael Sumner
Institute for Marine and Antarctic Studies, University of Tasmania
Hobart, Australia
e-mail: mdsum...@gmail.com
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