Documentation

README.md

@@ -18,14 +18,12 @@ read FITS files.
 Installation
 ------------
 
-`AstroImage.jl` is available for Julia 0.7 and later versions, and can be
+`AstroImage.jl` is available for Julia 1.0 and later versions, and can be
 installed with [Julia built-in package
-manager](https://docs.julialang.org/en/v1/stdlib/Pkg/).  This packages is not
-yet registered, after entering into the package manager by pressing `]` run the
-command
+manager](https://docs.julialang.org/en/v1/stdlib/Pkg/).
 
 ```julia
-pkg> add https://github.com/JuliaAstro/AstroImages.jl
+pkg> add AstroImages
 ```
 
 Usage
@@ -65,15 +63,33 @@ the same syntax as `load`.  This command:
 
 ```julia
 julia> img = AstroImage("file.fits")
-AstroImages.AstroImage{UInt16,ColorTypes.Gray}[...]
+AstroImages.AstroImage{UInt16,ColorTypes.Gray,1,Float64}[...]
 ```
 
-will read the first extension from the `file.fits` file and wrap its content in
-a `Matrix{Gray}`, that can be easily used with `Images.jl` and related packages.
+will read the first valid extension from the `file.fits` file and wrap its content in
+a `NTuple{N, Matrix{Gray}}`, that can be easily used with `Images.jl` and related packages.
 
 If you are working in a Jupyter notebook, an `AstroImage` object is
 automatically rendered as a PNG image.
 
+`AstroImage` automatically extracts and store `wcs` information of images in a `NTuple{N, WCSTransform}`.
+
+## Forming RGB image
+`AstroImage` can automatically construct a RGB image if 3 different colour band data is given.
+
+```julia
+julia> img = AstroImage(RGB, ("file1.fits","file2.fits", "file3.fits"))
+```
+Where 1st index of `file1.fits`, `file2.fits`, `file3.fits` contains band data of red, blue and  green channels respectively.
+
+Optionally, `ccd2rgb` method can be used to form a coloured image from 3 bands without creating an `AstroImage`.
+
+The formed image can be accessed using `img.property.rgb_image`. 
+`set_brightness!` and `set_contrast!` methods can be used to change brightness and contrast of formed `rgb_image`.
+`add_label!` method can be used to add/store Astronomical labels in an `AstroImage`.
+`reset!` method resets `brightness`, `contrast` and `label` fields to defaults and construct a fresh `rgb_image` without any brightness, contrast operations.
+
+
 ## Plotting an AstroImage
 
 An `AstroImage` object can be plotted with `Plots.jl` package.  Just use

src/AstroImages.jl

@@ -174,6 +174,11 @@ function render(img::AstroImage{T,C,N}, header_number = 1) where {T,C,N}
     return colorview(C, f.(_float.(img.data[header_number])))
 end
 
+"""
+    set_brightness!(img::AstroImage, value::AbstractFloat)
+
+Sets brightness of `rgb_image` to value.
+"""
 function set_brightness!(img::AstroImage, value::AbstractFloat)
     if isdefined(img.property, :rgb_image)
         diff = value - img.property.brightness
@@ -183,6 +188,12 @@ function set_brightness!(img::AstroImage, value::AbstractFloat)
         throw(DomainError(value, "Can't apply operation. AstroImage dosen't contain :rgb_image"))
     end
 end
+
+"""
+    set_contrast!(img::AstroImage, value::AbstractFloat)
+
+Sets contrast of rgb_image to value.
+"""
 function set_contrast!(img::AstroImage, value::AbstractFloat)
     if isdefined(img.property, :rgb_image)
         diff = (value / img.property.contrast)
@@ -193,9 +204,24 @@ function set_contrast!(img::AstroImage, value::AbstractFloat)
         throw(DomainError(value, "Can't apply operation. AstroImage dosen't contain :rgb_image"))
     end
 end
+
+"""
+    add_label!(img::AstroImage, x::Real, y::Real, label::String)
+
+Stores label to coordinates (x,y) in AstroImage's property label.
+"""
 function add_label!(img::AstroImage, x::Real, y::Real, label::String)
     push!(img.property.label, ((x,y), label))
 end
+
+"""
+    reset!(img::AstroImage)
+
+Resets AstroImage property fields.
+
+Sets brightness to 0.0, contrast to 1.0, empties label
+and form a fresh rgb_image without any brightness, contrast operations on it.
+"""
 function reset!(img::AstroImage{T,C,N}) where {T,C,N}
     img.property.contrast = 1.0
     img.property.brightness = 0.0