Support ARGB32 images (#45)

Fixes JuliaIO/FileIO.jl#352

Co-authored-by: Drvi <tomas.drvostep@gmail.com>

Author: timholy

Project.toml

@@ -1,7 +1,7 @@
 name = "PNGFiles"
 uuid = "f57f5aa1-a3ce-4bc8-8ab9-96f992907883"
 authors = ["Ian Butterworth", "Tomáš Drvoštěp"]
-version = "0.3.11"
+version = "0.3.12"
 
 [deps]
 Base64 = "2a0f44e3-6c83-55bd-87e4-b1978d98bd5f"

src/io.jl

@@ -367,7 +367,7 @@ function _save(png_ptr, info_ptr, image::S;
         end
     else
         image_eltype = eltype(image)
-        if (image_eltype <: BGR || image_eltype <: BGRA || image_eltype <: ABGR)
+        if (image_eltype <: BGR || image_eltype <: BGRA || image_eltype <: ABGR || image_eltype <: ARGB32)
             png_set_bgr(png_ptr)
         end
 
@@ -515,14 +515,11 @@ _get_bit_depth(img::AbstractArray{<:Bool}) = 8  # TODO: write 1 bit-depth images
 _get_bit_depth(img::AbstractArray{<:UInt8}) = 8
 _get_bit_depth(img::AbstractArray{<:UInt16}) = 16
 
-_get_color_type(x::AbstractArray{<:Gray{T}}) where {T} = PNG_COLOR_TYPE_GRAY
-_get_color_type(x::AbstractArray{<:GrayA{T}}) where {T} = PNG_COLOR_TYPE_GRAY_ALPHA
-_get_color_type(x::AbstractArray{<:RGB{T}}) where {T} = PNG_COLOR_TYPE_RGB
-_get_color_type(x::AbstractArray{<:RGBA{T}}) where {T} = PNG_COLOR_TYPE_RGBA
-_get_color_type(x::AbstractArray{<:BGR{T}}) where {T} = PNG_COLOR_TYPE_RGB
-_get_color_type(x::AbstractArray{<:BGRA{T}}) where {T} = PNG_COLOR_TYPE_RGBA
-_get_color_type(x::AbstractArray{<:ARGB{T}}) where {T} = PNG_COLOR_TYPE_RGBA
-_get_color_type(x::AbstractArray{<:ABGR{T}}) where {T} = PNG_COLOR_TYPE_RGBA
+_get_color_type(x::AbstractArray{<:Gray}) = PNG_COLOR_TYPE_GRAY
+_get_color_type(x::AbstractArray{<:GrayA}) = PNG_COLOR_TYPE_GRAY_ALPHA
+_get_color_type(x::AbstractArray{<:AbstractRGB}) = PNG_COLOR_TYPE_RGB
+_get_color_type(x::AbstractArray{<:AbstractARGB}) = PNG_COLOR_TYPE_RGBA
+_get_color_type(x::AbstractArray{<:AbstractRGBA}) = PNG_COLOR_TYPE_RGBA
 _get_color_type(x::IndirectArray) = PNG_COLOR_TYPE_PALETTE
 function _get_color_type(
         x::AbstractArray{T, N}

test/test_synthetic_images.jl

@@ -33,6 +33,7 @@ synth_imgs = [
     "GrayA" => rand(GrayA, 127, 257),
     "RGB" => rand(RGB, 127, 257),
     "RGBA" => rand(RGBA, 127, 257),
+    "ARGB32" => reinterpret(ARGB32, rand(UInt32, 127, 257)),
     "Gray-N0f8" => rand(Gray{N0f8}, 127, 257),
     "GrayA-N0f8" => rand(GrayA{N0f8}, 127, 257),
     "RGB-N0f8" => rand(RGB{N0f8}, 127, 257),
@@ -88,7 +89,7 @@ edge_case_imgs = [
                 @test typeof(read_in_pngf) <: AbstractMatrix
             end
             @testset "compare" begin
-                @test all(expected .≈ read_in_pngf)
+                @test eltype(eltype(expected)) <: N0f8 ? expected == read_in_pngf : all(expected .≈ read_in_pngf)
             end
             global read_in_immag = _standardize_grayness(ImageMagick.load(fpath))
             @testset "$(case): ImageMagick read type equality" begin