Gray image can not be displayed as an true image

[Gnimuc]

Take a look at the following toy example:

using Plots, Images; #gr()
plot(grayim(rand(16,16)))

It seems that Plots considered the gray image as a common matrix. However, other image types can be displayed correctly. I guess this might due to the data structure of the gray image which is indeed a plain Matrix.

[tbreloff]

Hmm this is tricky. The type from grayim is a subset of AbstractArray{Float64,2}... not the same as if you loaded it from a file. In order to define a recipe that would work, I'd have to add a dependency on Images (which I don't want). Another option would be to add the recipe to Images itself, which would require a dependency on RecipesBase (cc @timholy)

The current workaround is to explicitly map this to a matrix of colors:

using Plots, Images
img = convert(Matrix{Gray}, grayim(rand(16,16)))
plot(img)

[timholy]

In the "new Images" (see JuliaImages/Images.jl#542, especially JuliaImages/Images.jl#542 (comment)) it will return something of type Gray, so your intention will be clear.

[tbreloff]

@timholy do you mean that with the new Images the convert will be unnecessary? (I.e. The grayim call will return a "matrix of Gray"?) If so, that's great... nothing to be done.

[timholy]

Well, grayim is going away, it will be called colorview(Gray, rand(16, 16)).

[timholy]

But yes, nothing you need to do here.

[tbreloff]

Cool... gonna close this then. Thanks!