make MaskMulti more convenient

Author: lorenzoh

src/items/mask.jl

@@ -16,17 +16,22 @@ mask = MaskMulti(rand(1:3, 100, 100))
 showitem(mask)
 ```
 """
-struct MaskMulti{N, T, B} <: AbstractArrayItem{N, T}
+struct MaskMulti{N, T<:Integer, U, B} <: AbstractArrayItem{N, T}
     data::AbstractArray{T, N}
-    classes::AbstractVector{T}
+    classes::AbstractVector{U}
     bounds::AbstractArray{<:SVector{N, B}, N}
 end
 
 
-function MaskMulti(a::AbstractArray, classes = unique(a), bounds = makebounds(size(a)))
-    return MaskMulti(a, classes = bounds)
+function MaskMulti(a::AbstractArray, classes = unique(a))
+    bounds = makebounds(size(a))
+    minimum(a) >= 1 || error("Class values must start at 1")
+    return MaskMulti(a, classes, bounds)
 end
 
+MaskMulti(a::AbstractArray{<:Gray{T}}, args...) where T = MaskMulti(reinterpret(T, a), args...)
+MaskMulti(a::AbstractArray{<:Normed{T}}, args...) where T = MaskMulti(reinterpret(T, a), args...)
+
 Base.show(io::IO, mask::MaskMulti{N, T}) where {N, T} =
     print(io, "MaskMulti{$N, $T}() with size $(size(itemdata(mask))) and $(length(mask.classes)) classes")
 
@@ -125,9 +130,10 @@ end
 
 function mask_extrapolation(
         mask::AbstractArray{T};
+        t = T,
         degree = Constant(),
         boundary = Flat()) where T
-    itp = interpolate(T, T, mask, BSpline(degree))
+    itp = interpolate(t, t, mask, BSpline(degree))
     etp = extrapolate(itp, Flat())
     return etp
 end

src/preprocessing.jl

@@ -214,9 +214,7 @@ end
 function apply!(buf, tfm::OneHot{T}, item::MaskMulti; randstate = nothing) where T
     mask = itemdata(item)
     a = itemdata(buf)
-    @show a[1:6]
     fill!(a, zero(T))
-    @show a[1:6]
 
     for I in CartesianIndices(mask)
         a[I, mask[I]] = one(T)

src/projective/base.jl

@@ -67,7 +67,7 @@ function apply(tfm::ProjectiveTransform, item::Item; randstate = getrandstate(tf
     bounds = getbounds(item)
     P = getprojection(tfm, bounds; randstate = randstate)
     indices = cropindices(tfm, P, bounds; randstate = randstate)
-    return project(P, item, indices)
+    return P isa IdentityTransformation ? item : project(P, item, indices)
 end
 
 # For the buffered version, `project!` is used. Of course the size

src/projective/crop.jl

@@ -13,6 +13,8 @@ struct Crop{N, F<:CropFrom} <: AbstractCrop
     from::F
 end
 
+Crop(sz) = Crop(sz, FromOrigin())
+
 
 
 function apply(crop::Crop, item::Item; randstate = getrandstate(crop))