add get functions for wavelet types

JuliaDSP · Mar 12, 2015 · f68dc9c · f68dc9c
1 parent 42b255e
commit f68dc9c
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Showing 4 changed files with 67 additions and 36 deletions.
diff --git a/README.md b/README.md
@@ -42,6 +42,7 @@ API
 wavelet(w::WT.WaveletClass, boundary::WaveletBoundary=Periodic)  # defaults to filter
 waveletfilter(w::WT.WaveletClass, boundary::WaveletBoundary=Periodic)
 waveletls(w::WT.WaveletClass, boundary::WaveletBoundary=Periodic)
+
 # DWT (discrete wavelet transform)
 dwt(x::AbstractArray, wt::DiscreteWavelet, L::Integer=maxtransformlevels(x))
 idwt(x::AbstractArray, wt::DiscreteWavelet, L::Integer=maxtransformlevels(x))
@@ -74,12 +75,21 @@ The numbers for orthogonal wavelets indicate the number vanishing moments of the
 | `Vaidyanathan` | vaid | `OrthoWaveletClass` |  |
 | `CDF` | cdf | `BiOrthoWaveletClass` | (9,7) |
 
-Class information functions
+Class information
 ```julia
 class(::WaveletClass) ::ASCIIString         # class full name
 name(::WaveletClass) ::ASCIIString          # type short name
 vanishingmoments(::WaveletClass)            # vanishing moments of wavelet function
 ```
+Transform type information
+```julia
+length(f::OrthoFilter)						# length of filter
+qmf(f::OrthoFilter)							# quadrature mirror filter
+name(f::OrthoFilter)
+makeqmfpair(f::OrthoFilter, fw::Bool=true, T::Type=eltype(qmf(f)))
+makereverseqmfpair(f::OrthoFilter, fw::Bool=true, T::Type=eltype(qmf(f)))
+name(s::GLS)
+```
 
 Examples
 ---------

diff --git a/src/transforms_filter.jl b/src/transforms_filter.jl
@@ -6,22 +6,6 @@
 #
 ##################################################################################
 
-function makeqmf(h::AbstractVector, fw::Bool, T::Type=eltype(h))
-    scfilter, dcfilter = makereverseqmf(h, fw, T)
-    return reverse(scfilter), reverse(dcfilter)
-end
-function makereverseqmf(h::AbstractVector, fw::Bool, T::Type=eltype(h))
-    h = convert(Vector{T}, h)
-    if fw
-        scfilter = reverse(h)
-        dcfilter = mirror(h)
-    else
-        scfilter = h
-        dcfilter = reverse(mirror(h))
-    end
-    return scfilter, dcfilter
-end
-
 for (Xwt) in (:dwt!, :wpt!)
 @eval begin
     # pseudo "inplace" by copying
@@ -39,7 +23,7 @@ end
 # writes to y
 function dwt!{T<:FloatingPoint}(y::AbstractVector{T}, x::AbstractVector{T}, filter::OrthoFilter, L::Integer, fw::Bool)
     si = Array(T, length(filter)-1)       # tmp filter vector
-    scfilter, dcfilter = makereverseqmf(filter.qmf, fw, T)
+    scfilter, dcfilter = makereverseqmfpair(filter, fw, T)
 
     dwt!(y, x, filter, L, fw, dcfilter, scfilter, si)
     return y
@@ -68,7 +52,7 @@ function dwt!{T<:FloatingPoint}(y::AbstractVector{T}, x::AbstractVector{T}, filt
             # detail coefficients
             filtdown!(dcfilter, si, y, detailindex(n,l,1), detailn(n,l), s, 1,-filtlen+1, true)
             # scaling coefficients
-            filtdown!(scfilter, si, y,                1, detailn(n,l), s, 1, 0, false)
+            filtdown!(scfilter, si, y, 1, detailn(n,l), s, 1, 0, false)
         else
             # scaling coefficients
             filtup!(false, scfilter, si, y, 1, detailn(n,l-1), s, 1, -filtlen+1, false)
@@ -91,7 +75,7 @@ function unsafe_dwt1level!{T<:FloatingPoint}(y::AbstractVector{T}, x::AbstractVe
         # detail coefficients
         filtdown!(dcfilter, si, y, detailindex(n,l,1), detailn(n,l), x, 1,-filtlen+1, true)
         # scaling coefficients
-        filtdown!(scfilter, si, y,                1, detailn(n,l), x, 1, 0, false)
+        filtdown!(scfilter, si, y, 1, detailn(n,l), x, 1, 0, false)
     else
         # scaling coefficients
         filtup!(false, scfilter, si, y, 1, detailn(n,l-1), x, 1, -filtlen+1, false)
@@ -107,7 +91,7 @@ function dwt!{T<:FloatingPoint}(y::Matrix{T}, x::AbstractMatrix{T}, filter::Orth
     n = size(x,1)
     si = Array(T, length(filter)-1)       # tmp filter vector
     tmpvec = Array(T,n<<1)             # tmp storage vector
-    scfilter, dcfilter = makereverseqmf(filter.qmf, fw, T)
+    scfilter, dcfilter = makereverseqmfpair(filter, fw, T)
 
     dwt!(y, x, filter, L, fw, dcfilter, scfilter, si, tmpvec)
     return y
@@ -203,7 +187,7 @@ function wpt!{T<:FloatingPoint}(y::AbstractVector{T}, x::AbstractVector{T}, filt
     si = Array(T, length(filter)-1)
     ns = ifelse(fw, length(x)>>1, length(x))
     snew = Array(T, ns)
-    scfilter, dcfilter = makereverseqmf(filter.qmf, fw, T)
+    scfilter, dcfilter = makereverseqmfpair(filter, fw, T)
 
     wpt!(y, x, filter, tree, fw, dcfilter, scfilter, si, snew)
     return y

diff --git a/src/wavelettypes.jl b/src/wavelettypes.jl
@@ -13,6 +13,10 @@ export  DiscreteWavelet,
         #CPBoundary,
         #
         OrthoFilter,
+        qmf,
+        name,
+        makereverseqmfpair,
+        makeqmfpair,
         #BiOrthoFilter,
         LSstep,
         GLS,
@@ -22,6 +26,7 @@ export  DiscreteWavelet,
         waveletfilter,
         waveletls
 
+using ..Util
 using Compat
 
 # TYPE HIERARCHY
@@ -228,8 +233,8 @@ end
 # IMPLEMENTATIONS OF FilterWavelet
 
 immutable OrthoFilter{T<:WaveletBoundary} <: FilterWavelet{T}
-    qmf::Vector{Float64}        # quadrature mirror filter
-    name::ASCIIString           # filter short name
+    qmf     ::Vector{Float64}        # quadrature mirror filter
+    name    ::ASCIIString            # filter short name
     OrthoFilter(qmf, name) = new(qmf, name)
 end
 
@@ -246,6 +251,32 @@ function OrthoFilter{WC<:WT.OrthoWaveletClass, T<:WaveletBoundary}(w::WC, ::T=DE
 end
 
 Base.length(f::OrthoFilter) = length(f.qmf)
+qmf(f::OrthoFilter) = f.qmf
+name(f::OrthoFilter) = f.name
+
+# scale filter by scalar
+function scale{T<:WaveletBoundary}(f::OrthoFilter{T}, a::Number)
+    return OrthoFilter{T}(f.qmf.*a, f.name)
+end
+
+# quadrature mirror filter pair
+function makeqmfpair(f::OrthoFilter, fw::Bool=true, T::Type=eltype(qmf(f)))
+    scfilter, dcfilter = makereverseqmfpair(f, fw, T)
+    return reverse(scfilter), reverse(dcfilter)
+end
+
+# reversed quadrature mirror filter pair
+function makereverseqmfpair(f::OrthoFilter, fw::Bool=true, T::Type=eltype(qmf(f)))
+    h = convert(Vector{T}, qmf(f))
+    if fw
+        scfilter = reverse(h)
+        dcfilter = mirror(h)
+    else
+        scfilter = h
+        dcfilter = reverse(mirror(h))
+    end
+    return scfilter, dcfilter
+end
 
 #immutable BiOrthoFilter{T<:WaveletBoundary} <: FilterWavelet{T}
 #    qmf1::Vector{Float64}       # quadrature mirror filter 1
@@ -254,17 +285,12 @@ Base.length(f::OrthoFilter) = length(f.qmf)
 #    BiOrthoFilter(qmf1, qmf2, name) = new(qmf1, qmf2, name)
 #end
 
-# scale filter by scalar
-function scale{T<:WaveletBoundary}(f::OrthoFilter{T}, a::Number)
-    return OrthoFilter{T}(f.qmf.*a, f.name)
-end
-
 # IMPLEMENTATIONS OF LSWavelet
 
 immutable LSstep
-    stept::Char             # step type: 'p' for predict, 'u' for update
-    coef::Vector{Float64}   # lifting coefficients
-    shift::Int              # + left shift, - right shift
+    stept   ::Char              # step type: 'p' for predict, 'u' for update
+    coef    ::Vector{Float64}   # lifting coefficients
+    shift   ::Int               # + left shift, - right shift
     function LSstep(stept,coef,shift)
         @assert stept=='p' || stept=='u'
         return new(stept,coef,shift)
@@ -273,10 +299,10 @@ end
 
 # general lifting scheme
 immutable GLS{T<:WaveletBoundary} <: LSWavelet{T}
-    step::Vector{LSstep}    # steps to be taken
-    norm1::Float64          # normalization of scaling coefs.
-    norm2::Float64          # normalization of detail coefs.
-    name::ASCIIString       # name of scheme
+    step    ::Vector{LSstep}    # steps to be taken
+    norm1   ::Float64           # normalization of scaling coefs.
+    norm2   ::Float64           # normalization of detail coefs.
+    name    ::ASCIIString       # name of scheme
     GLS(step, norm1, norm2, name) = new(step, norm1, norm2, name)
 end
 
@@ -287,6 +313,8 @@ function GLS{WC<:WT.WaveletClass, T<:WaveletBoundary}(w::WC, ::T=DEFAULT_BOUNDAR
     return GLS{T}(schemedef..., name)
 end
 
+name(s::GLS) = s.name
+
 
 # IMPLEMENTATIONS OF ContinuousWavelet
 

diff --git a/test/transforms.jl b/test/transforms.jl
@@ -262,4 +262,13 @@ end
 #...
 
 
+# ============= wavelet types ================
+print("transforms: wavelet types ...\n")
 
+wt = waveletfilter(WT.db2)
+@test length(wt) == 4
+same = Wavelets.name(wt) == "db2"
+@test same
+
+wt = waveletls(WT.db2)
+@test Wavelets.name(wt) == "db2"