Add image function (#14)

* Permute the TIFF dimensions by default

* Add 'image' function

README.md

@@ -39,6 +39,19 @@ julia> metadata = GeoTIFF.metadata(geotiff)
 GeoTIFF.Metadata(...)
 ```
 
+And use the `GeoTIFF.image` function to get the image with corrected axes:
+
+```julia
+julia> GeoTIFF.image(geotiff)
+100×100 PermutedDimsArray(::TiffImages.DenseTaggedImage{...}, (2, 1)) with eltype RGB{N0f16}:
+ RGB(1.0, 1.0, 1.0)  RGB(1.0, 1.0, 1.0)  RGB(1.0, 1.0, 1.0)  RGB(1.0, 1.0, 1.0)  …  RGB(1.0, 1.0, 1.0)  RGB(1.0, 1.0, 1.0)  RGB(1.0, 1.0, 1.0)
+ RGB(1.0, 1.0, 1.0)  RGB(1.0, 1.0, 1.0)  RGB(1.0, 1.0, 1.0)  RGB(1.0, 1.0, 1.0)     RGB(1.0, 1.0, 1.0)  RGB(1.0, 1.0, 1.0)  RGB(1.0, 1.0, 1.0)
+ RGB(1.0, 1.0, 1.0)  RGB(1.0, 1.0, 1.0)  RGB(1.0, 1.0, 1.0)  RGB(1.0, 1.0, 1.0)     RGB(1.0, 1.0, 1.0)  RGB(1.0, 1.0, 1.0)  RGB(1.0, 1.0, 1.0)
+ ⋮                                                                               ⋱                                          
+ RGB(1.0, 1.0, 1.0)  RGB(1.0, 1.0, 1.0)  RGB(1.0, 1.0, 1.0)  RGB(1.0, 1.0, 1.0)     RGB(1.0, 1.0, 1.0)  RGB(1.0, 1.0, 1.0)  RGB(1.0, 1.0, 1.0)
+ RGB(1.0, 1.0, 1.0)  RGB(1.0, 1.0, 1.0)  RGB(1.0, 1.0, 1.0)  RGB(1.0, 1.0, 1.0)     RGB(1.0, 1.0, 1.0)  RGB(1.0, 1.0, 1.0)  RGB(1.0, 1.0, 1.0)
+```
+
 GeoTIFF.jl defines several utilities to easily retrieve metadata information:
 
 ```julia

src/image.jl

@@ -7,8 +7,13 @@
 
 Image type returned by the [`GeoTIFF.load`](@ref) function.
 
-See the [`GeoTIFF.tiff`](@ref) and [`GeoTIFF.metadata`](@ref) functions
-to get the TIFF image and metadata respectively.
+See the [`GeoTIFF.metadata`](@ref) and [`GeoTIFF.image`](@ref) functions
+to get the metadata and the image with corrected axes, respectively.
+
+### Notes
+
+* The [`GeoTIFF.image`](@ref) function is necessary because 
+  the GeoTIFF format swaps the order of the image axes;
 """
 struct GeoTIFFImage{T,N,I<:AbstractTIFF{T,N}} <: AbstractArray{T,N}
   tiff::I
@@ -29,6 +34,13 @@ GeoTIFF metadata of the `geotiff` image.
 """
 metadata(geotiff::GeoTIFFImage) = geotiff.metadata
 
+"""
+    GeoTIFF.image(geotiff)
+
+Image of the `geotiff` with corrected axis.
+"""
+image(geotiff::GeoTIFFImage) = PermutedDimsArray(geotiff.tiff, (2, 1))
+
 """
     GeoTIFF.nchannels(geotiff)
 
@@ -41,7 +53,7 @@ nchannels(geotiff::GeoTIFFImage) = nchannels(geotiff.tiff)
 
 `i`'th channel of the `geotiff` image.
 """
-channel(geotiff::GeoTIFFImage, i) = mappedarray(c -> channel(c, i), geotiff.tiff)
+channel(geotiff::GeoTIFFImage, i) = mappedarray(c -> channel(c, i), image(geotiff))
 
 # AbstractArray interface
 Base.size(geotiff::GeoTIFFImage) = size(geotiff.tiff)

src/save.jl

@@ -28,7 +28,10 @@ end
 
 Save in the file `fname` an image (array of colors) `img` with passed GeoTIFF `metadata`.
 """
-save(fname, img::AbstractArray{<:WidePixelOrColorant}; kwargs...) = save(fname, DenseTaggedImage(img); kwargs...)
+function save(fname, img::AbstractArray{<:WidePixelOrColorant}; kwargs...)
+  tiff = DenseTaggedImage(PermutedDimsArray(img, (2, 1)))
+  save(fname, tiff; kwargs...)
+end
 
 """
     GeoTIFF.save(fname, channels...; metadata=GeoTIFF.Metadata())

test/runtests.jl

@@ -27,6 +27,7 @@ savedir = mktempdir()
     geotiff = GeoTIFF.load(joinpath(datadir, "test.tif"))
     metadata = GeoTIFF.metadata(geotiff)
     @test eltype(geotiff) <: RGB
+    @test size(geotiff) == (100, 100)
     @test isnothing(GeoTIFF.rastertype(metadata))
     @test isnothing(GeoTIFF.modeltype(metadata))
     @test isnothing(GeoTIFF.epsgcode(metadata))
@@ -36,6 +37,7 @@ savedir = mktempdir()
     geotiff = GeoTIFF.load(joinpath(datadir, "test_gray.tif"))
     metadata = GeoTIFF.metadata(geotiff)
     @test eltype(geotiff) <: Gray
+    @test size(geotiff) == (108, 108)
     @test isnothing(GeoTIFF.rastertype(metadata))
     @test isnothing(GeoTIFF.modeltype(metadata))
     @test isnothing(GeoTIFF.epsgcode(metadata))
@@ -46,12 +48,26 @@ savedir = mktempdir()
     geotiff = GeoTIFF.load(joinpath(datadir, "utm.tif"))
     metadata = GeoTIFF.metadata(geotiff)
     @test eltype(geotiff) <: RGB
+    @test size(geotiff) == (100, 100)
     @test GeoTIFF.rastertype(metadata) == GeoTIFF.PixelIsArea
     @test GeoTIFF.modeltype(metadata) == GeoTIFF.Projected2D
     @test GeoTIFF.epsgcode(metadata) == 32617
     A = [121.52985600000001 0.0; 0.0 -164.762688]
     b = [688258.223819, 4.555765966137e6]
     @test GeoTIFF.affineparams2D(metadata) == (A, b)
+
+    # GeoTIFF format swaps axis order
+    geotiff = GeoTIFF.load(joinpath(datadir, "natural_earth_1.tif"))
+    metadata = GeoTIFF.metadata(geotiff)
+    @test eltype(geotiff) <: RGB
+    @test size(geotiff) == (81, 162)
+    @test size(GeoTIFF.image(geotiff)) == (162, 81)
+    @test GeoTIFF.rastertype(metadata) == GeoTIFF.PixelIsArea
+    @test GeoTIFF.modeltype(metadata) == GeoTIFF.Geographic2D
+    @test GeoTIFF.epsgcode(metadata) == 4326
+    A = [2.222222222222001 0.0; 0.0 -2.222222222222001]
+    b = [-180.0, 90.0]
+    @test GeoTIFF.affineparams2D(metadata) == (A, b)
   end
 
   @testset "GeoTIFFImage" begin
@@ -69,6 +85,13 @@ savedir = mktempdir()
     @test geotiff[1, 1] == color
     @test IndexStyle(geotiff) === IndexCartesian()
 
+    # image function
+    geotiff = GeoTIFF.load(joinpath(datadir, "natural_earth_1.tif"))
+    img = GeoTIFF.image(geotiff)
+    @test size(img) == reverse(size(geotiff))
+    @test eltype(img) === eltype(geotiff)
+    @test img == permutedims(geotiff, (2, 1))
+
     # multi-channel image
     file = joinpath(savedir, "multi.tiff")
     channel1 = rand(10, 10)