add CUDA testset for Gabor and LogGabor

Currently we don't have very native CUDA support for these two kernels,
so the test set mainly serves as "okay, we can convert the lazy kernel
array to CuArray by following the steps in tests and then use GPU to do
multiplication and fft"

Author: johnnychen94

test/cuda/gaborkernels.jl

@@ -0,0 +1,66 @@
+@testset "GaborKernels" begin
+
+@testset "Gabor" begin
+    # Gray
+    img = float32.(TestImages.shepp_logan(127))
+    kern = Kernel.Gabor(size(img), 3.0f0, 0f0)
+    img_freq = fft(channelview(img))
+    kern_freq = ifftshift(fft(kern))
+    out = abs.(ifft(img_freq .* kern_freq))
+
+    # TODO(johnnychen94): currently Gabor can't be converted to CuArray directly and thus
+    # FFTW is applied in the CPU side.
+    img_cu = CuArray(img)
+    img_freq = fft(channelview(img_cu))
+    kern_freq = CuArray(ifftshift(fft(kern)))
+    out_cu = abs.(ifft(img_freq .* kern_freq))
+
+    @test out ≈ Array(out_cu)
+
+    # RGB
+    img = float32.(testimage("monarch"))
+    kern = Kernel.Gabor(size(img), 3.0f0, 0f0)
+    kern_freq = reshape(ifftshift(fft(kern)), 1, size(kern)...)
+    img_freq = fft(channelview(img), 2:3)
+    out = colorview(RGB, abs.(ifft(img_freq .* kern_freq)))
+
+    img_cu = CuArray(img)
+    kern_freq = CuArray(reshape(ifftshift(fft(kern)), 1, size(kern)...))
+    img_freq = fft(channelview(img_cu), 2:3)
+    out_cu = colorview(RGB, abs.(ifft(img_freq .* kern_freq)))
+
+    @test out ≈ Array(out_cu)
+end
+
+@testset "LogGabor" begin
+    # Gray
+    img = float32.(TestImages.shepp_logan(127))
+    kern = Kernel.LogGabor(size(img), 1.0f0/6, 0f0)
+    kern_freq = OffsetArrays.no_offset_view(ifftshift(kern))
+    img_freq = fft(channelview(img))
+    out = abs.(ifft(kern_freq .* img_freq))
+
+    # TODO(johnnychen94): remove this no_offset_view wrapper
+    img_cu = CuArray(img)
+    kern_freq = CuArray(OffsetArrays.no_offset_view(ifftshift(kern)))
+    img_freq = fft(channelview(img_cu))
+    out_cu = abs.(ifft(kern_freq .* img_freq))
+
+    @test out ≈ Array(out_cu)
+
+    # RGB
+    img = float32.(testimage("monarch"))
+    kern = Kernel.LogGabor(size(img), 1.0f0/6, 0f0)
+    kern_freq = reshape(ifftshift(kern), 1, size(kern)...)
+    img_freq = fft(channelview(img), 2:3)
+    out = colorview(RGB, abs.(ifft(img_freq .* kern_freq)))
+
+    img_cu = CuArray(img)
+    kern_freq = CuArray(reshape(ifftshift(kern), 1, size(kern)...))
+    img_freq = fft(channelview(img_cu), 2:3)
+    out_cu = colorview(RGB, abs.(ifft(img_freq .* kern_freq)))
+
+    @test out ≈ Array(out_cu)
+end
+
+end

test/cuda/runtests.jl

@@ -7,11 +7,15 @@ using ImageBase
 using ImageQualityIndexes
 using Test
 using Random
+using FFTW
+using OffsetArrays
+using CUDA.Adapt
 
 CUDA.allowscalar(false)
 
 @testset "ImageFiltering" begin
     if CUDA.functional()
         include("models.jl")
+        include("gaborkernels.jl")
     end
 end