diff --git a/Project.toml b/Project.toml
index 12b28a3..d4c291f 100644
--- a/Project.toml
+++ b/Project.toml
@@ -1,7 +1,7 @@
 name = "HCIToolbox"
 uuid = "b6cd55e5-4d02-4e12-b82c-005f67e784bf"
 authors = ["Miles Lucas <mdlucas@hawaii.edu>"]
-version = "0.6.3"
+version = "0.6.4"
 
 [deps]
 CoordinateTransformations = "150eb455-5306-5404-9cee-2592286d6298"
@@ -9,6 +9,8 @@ FillArrays = "1a297f60-69ca-5386-bcde-b61e274b549b"
 ImageTransformations = "02fcd773-0e25-5acc-982a-7f6622650795"
 Interpolations = "a98d9a8b-a2ab-59e6-89dd-64a1c18fca59"
 LinearAlgebra = "37e2e46d-f89d-539d-b4ee-838fcccc9c8e"
+LossFunctions = "30fc2ffe-d236-52d8-8643-a9d8f7c094a7"
+Optim = "429524aa-4258-5aef-a3af-852621145aeb"
 PaddedViews = "5432bcbf-9aad-5242-b902-cca2824c8663"
 Rotations = "6038ab10-8711-5258-84ad-4b1120ba62dc"
 SpecialFunctions = "276daf66-3868-5448-9aa4-cd146d93841b"
@@ -21,6 +23,8 @@ CoordinateTransformations = "0.5, 0.6"
 FillArrays = "0.6, 0.7, 0.8, 0.9, 0.10, 0.11, 0.12, 0.13"
 ImageTransformations = "0.9"
 Interpolations = "0.12, 0.13"
+LossFunctions = "0.11"
+Optim = "1"
 PaddedViews = "0.5"
 Rotations = "1"
 SpecialFunctions = "0.10, 1, 2"
diff --git a/src/HCIToolbox.jl b/src/HCIToolbox.jl
index 25d61ca..3a812a5 100644
--- a/src/HCIToolbox.jl
+++ b/src/HCIToolbox.jl
@@ -44,5 +44,6 @@ include("angles.jl")
 include("scaling.jl")
 include("profiles.jl")
 
+include("cutout.jl")
 
 end
diff --git a/src/cutout.jl b/src/cutout.jl
new file mode 100644
index 0000000..2fb57cf
--- /dev/null
+++ b/src/cutout.jl
@@ -0,0 +1,61 @@
+
+struct CutoutView{T,N,M<:AbstractArray{T,N},CT,IT} <: AbstractArray{T,N}
+    parent::M
+    center::CT
+    indices::IT
+    fill::T
+end
+
+
+function CutoutView(parent::AbstractArray{T}, center, _size; fill=zero(T)) where T
+    
+    xlims = extrema(axes(parent, 1))
+    ylims = extrema(axes(parent, 2))
+
+    half_length = ones(Int, 2) .* _size ./ 2
+    minx = max(xlims[begin], round(Int, center[begin] - half_length[begin]))
+    miny = max(ylims[begin], round(Int, center[end] - half_length[end]))
+    maxx = minx + round(Int, half_length[begin] * 2) - 1
+    maxy = miny + round(Int, half_length[end] * 2) - 1
+    inds = (minx:maxx, miny:maxy,)
+
+    return CutoutView(parent, center, inds, T(fill))
+end
+
+function CutoutView(parent::AbstractArray{T}, _size; fill=zero(T)) where T
+    center = HCIToolbox.center(parent)
+    xlims = extrema(axes(parent, 1))
+    ylims = extrema(axes(parent, 2))
+
+    half_length = ones(Int, 2) .* _size ./ 2
+    minx = max(xlims[begin], round(Int, center[begin] - half_length[begin]))
+    miny = max(ylims[begin], round(Int, center[end] - half_length[end]))
+    maxx = minx + round(Int, half_length[begin] * 2)
+    maxy = miny + round(Int, half_length[end] * 2)
+    inds = (minx:maxx, miny:maxy,)
+
+    return CutoutView(parent, center, inds, T(fill))
+end
+
+Base.parent(view::CutoutView) = view.parent
+Base.size(view::CutoutView) = map(length, view.indices)
+Base.copy(view::CutoutView) = CutoutView(copy(parent(view)), view.center, view.indices, view.fill)
+Base.axes(view::CutoutView) = view.indices
+
+
+@propagate_inbounds function Base.getindex(view::CutoutView{T,N}, idx::Vararg{<:Integer,N}) where {T,N}
+    @boundscheck checkbounds(parent(view), idx...)
+
+    value = convert(T, parent(view)[idx...])
+    return value
+    # ifelse(inside_annulus(view, idx...), , view.fill)
+end
+
+# @propagate_inbounds function Base.setindex!(view::CutoutView{T,N}, val, idx::Vararg{<:Integer,N}) where {T,N}
+#     @boundscheck checkbounds(parent(view), idx...)
+#     if inside_annulus(view, idx...)
+#         parent(view)[idx...] = val
+#     else
+#         view.fill
+#     end
+# end
diff --git a/src/inject.jl b/src/inject.jl
index 755463a..e3ab754 100644
--- a/src/inject.jl
+++ b/src/inject.jl
@@ -124,6 +124,16 @@ function inject!(cube::AbstractArray{T,3}, kernel, angles=Zeros(size(cube, 3));
     return cube
 end
 
+function inject!(cube::AbstractArray{T,4}, kernel::AbstractArray{V,3}, angles=Zeros(size(cube, 4)); kwargs...) where {T,V}
+    @inbounds for idx in axes(cube, 3)
+        frame = @view cube[:, :, idx, :]
+        kern = @view kernel[:, :, idx]
+        inject!(frame, kern, angles; kwargs...)
+    end
+    return cube
+end
+
+
 function inject!(cube::AnnulusView{T}, kernel, angles=Zeros(size(cube, 3)); kwargs...) where T
     # All zeros position angles is actually 90° parallactic angle
     @inbounds for idx in cube.indices[2]
diff --git a/src/scaling.jl b/src/scaling.jl
index 624d76e..ad31aa9 100644
--- a/src/scaling.jl
+++ b/src/scaling.jl
@@ -1,4 +1,6 @@
 
+using LossFunctions
+using Optim
 using PaddedViews
 
 """
@@ -100,3 +102,33 @@ julia> scale_list([0.5, 2, 4])
 """
 scale_list(wavelengths) = maximum(wavelengths) ./ wavelengths
 
+function optimize_scale_list(spcube::AbstractArray{T,4}, scales, amps=ones(size(spcube, 3)); kwargs...) where T
+    # get temporal median first
+    spframe = median(spcube, dims=4)[:, :, :, 1]
+    return optimize_scale_list(spframe, scales; kwargs...)
+end
+
+function optimize_scale_list(spframe::AbstractArray{T,3}, scales, amps=ones(size(spframe, 3)); mask=trues(size(spframe, 1), size(spframe, 2))) where T
+    reference_frame = @view spframe[:, :, end]
+    N_wl = size(spframe, 3)
+    best_scales = ones(N_wl)
+    best_flux = ones(N_wl)
+    for wl_idx in axes(spframe, 3)[begin:end - 1]
+        current_frame = @view spframe[:, :, wl_idx]
+        func(X) = _scale_opt_func(current_frame, reference_frame, X[begin], X[end], mask)
+        P0 = T[scales[wl_idx], amps[wl_idx]]
+        result = optimize(func, P0, NelderMead(); autodiff=:forward)
+        @info "Finished optimizing (wl=$wl_idx/$N_wl)" result
+        X = Optim.minimizer(result)
+        best_scales[wl_idx] = X[begin]
+        best_flux[wl_idx] = X[end]
+    end
+    return (;scales=best_scales, fluxes=best_flux)
+end
+
+function _scale_opt_func(frame, reference, scale, amp=1, mask=trues(frame))
+    scale < 1 && return Inf
+    scaled_frame = amp .* HCIToolbox.scale(frame, scale)
+    # get loss
+    return sum(L2DistLoss(),  mask .* (scaled_frame .- reference))
+end
\ No newline at end of file