From 59d5bc877db66e4934cccd701ba209effaccb48c Mon Sep 17 00:00:00 2001
From: Johnny Chen <johnnychen94@hotmail.com>
Date: Wed, 3 Nov 2021 04:40:22 +0800
Subject: [PATCH] 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"
---
 test/cuda/gaborkernels.jl | 66 +++++++++++++++++++++++++++++++++++++++
 test/cuda/runtests.jl     |  4 +++
 2 files changed, 70 insertions(+)
 create mode 100644 test/cuda/gaborkernels.jl

diff --git a/test/cuda/gaborkernels.jl b/test/cuda/gaborkernels.jl
new file mode 100644
index 0000000..4b217f7
--- /dev/null
+++ b/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
diff --git a/test/cuda/runtests.jl b/test/cuda/runtests.jl
index 5789d00..f86b6dc 100644
--- a/test/cuda/runtests.jl
+++ b/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