Merge d1edf06 into ae7af2d

REQUIRE

@@ -3,3 +3,5 @@ FITSIO 0.12
 FileIO
 Images
 RecipesBase
+Interact
+ImageMagick

src/AstroImages.jl

@@ -2,7 +2,7 @@ __precompile__()
 
 module AstroImages
 
-using FITSIO, FileIO, Images
+using FITSIO, FileIO, Images, Interact
 
 export load, AstroImage
 

src/showmime.jl

@@ -1,3 +1,19 @@
+_brightness_contrast(color, matrix::AbstractMatrix{T}, brightness, contrast) where {T} =
+    @. color(matrix / 255 * T(contrast) + T(brightness) / 255)
+
+"""
+    brightness_contrast(image::AstroImage; brightness_range = 0:255, contrast_range = 1:1000)
+
+Visualize the fits image by changing the brightness and contrast of image.
+Users can also provide their own range as keyword arguments.
+"""
+function brightness_contrast(img::AstroImage{T,C}; brightness_range = 0:255,
+                             contrast_range = 1:1000) where {T,C}
+    @manipulate for brightness  in brightness_range, contrast in contrast_range
+        _brightness_contrast(C, img.data, brightness, contrast)
+    end
+end
+
 # This is used in Jupyter notebooks
-Base.show(io::IO, mime::MIME"image/png", img::AstroImage; kwargs...) =
-    show(io, mime, render(img), kwargs...)
+Base.show(io::IO, mime::MIME"text/html", img::AstroImage; kwargs...) =
+    show(io, mime, brightness_contrast(img), kwargs...)

test/runtests.jl

@@ -1,7 +1,8 @@
-using AstroImages, FITSIO, Images, Random
+using AstroImages, FITSIO, Images, Random, Widgets
+
 using Test
 
-import AstroImages: _float, render
+import AstroImages: _float, render, _brightness_contrast, brightness_contrast
 
 @testset "Conversion to float and fixed-point" begin
     @testset "Float" begin
@@ -44,6 +45,19 @@ end
     rm(fname, force = true)
 end
 
+@testset "Control contrast" begin
+    @test @inferred(_brightness_contrast(Gray, ones(Float32, 2, 2), 100, 100)) isa
+          Array{Gray{Float32},2}
+    Random.seed!(1)
+    M = rand(2, 2)
+    @test @inferred(_brightness_contrast(Gray, M, 100, 100)) ≈
+        Gray.([0.48471895908315565  0.514787046406301;
+               0.5280458879184159   0.39525854250610226]) rtol = 1e-12
+    @test @inferred(_brightness_contrast(Gray, M, 0,   255)) == Gray.(M)
+    @test @inferred(_brightness_contrast(Gray, M, 255,   0)) == Gray.(ones(size(M)))
+    @test @inferred(_brightness_contrast(Gray, M,   0,   0)) == Gray.(zeros(size(M)))
+    @test brightness_contrast(AstroImage(M)) isa Widgets.Widget{:manipulate,Any}
+end
 
 @testset "default handler" begin
     fname = tempname() * ".fits"
@@ -107,4 +121,5 @@ end
     end
     rm(fname, force = true)
 end
+
 include("plots.jl")