[Experimental] Synthesis of moving source

Project.toml

@@ -1,9 +1,10 @@
 name = "RoomAcoustics"
 uuid = "9b22aa7e-b0d0-4fe8-9c3b-2b8bf774f735"
 authors = ["zymon"]
-version = "0.1.0"
+version = "0.2.0"
 
 [deps]
+DSP = "717857b8-e6f2-59f4-9121-6e50c889abd2"
 LinearAlgebra = "37e2e46d-f89d-539d-b4ee-838fcccc9c8e"
 Random = "9a3f8284-a2c9-5f02-9a11-845980a1fd5c"
 StaticArrays = "90137ffa-7385-5640-81b9-e52037218182"

src/RoomAcoustics.jl

@@ -3,6 +3,7 @@ module RoomAcoustics
 using LinearAlgebra
 using StaticArrays
 using Statistics
+using DSP
 using Random
 using Random: GLOBAL_RNG
 
@@ -10,5 +11,6 @@ include("types.jl")
 include("utils.jl")
 include("directivity.jl")
 include("ISM.jl")
+include("moving_sources.jl")
 
 end # module

src/moving_sources.jl

@@ -0,0 +1,48 @@
+export synth_movement
+
+"""
+Experimental
+"""
+function synth_movement(
+    rx_path::AbstractVector{SVector{3, T}},
+    signal::AbstractVector{T},
+    tx::TxRx{T},
+    room::Room,
+    config::RIRConfig,
+    W_max::Integer = 2^11,
+) where {T<:Real}
+    P, N = length(rx_path), length(signal)
+
+    # Synthesise room impulse responses for given path
+    rirs = [ISM(tx, TxRx(p), room, config) for p in rx_path]
+
+    # Find synthesis parameters
+    best = typemax(Int);
+    W, L = 0, 0
+    for WW = 1:W_max, LL = 1:W_max-1
+        score = P*WW - LL*(P-1) - N;
+        if abs(score) <= best
+            best = abs(score);
+            W, L = WW, LL
+            best == 0 && break
+        end
+    end
+
+    # Compute synthesis window
+    w = sin.((1:W)*π/(W+1))
+
+    # Allocate memory for auxiliary signals
+    out = zeros(P*(W-L)+L)
+    dout = zeros(P*(W-L)+L)
+
+    # Synthesise
+    for (i, h) = enumerate(rirs)
+        sh = conv(h, signal)
+        f_s = (i-1)*(W-L) + 1
+        f_e = f_s + W - 1
+        out[f_s:f_e] += w .* sh[f_s:f_e]
+        dout[f_s:f_e] += w
+    end
+    out ./ dout
+end
+