aktu

src/ISM.jl

@@ -51,108 +51,6 @@ function ISM(
     end
 end
 
-"""
-
-References:
-[1] J. B. Allen and D. A. Berkley, “Image method for efficiently simulating small‐room acoustics,” The Journal of the Acoustical Society of America, vol. 65, no. 4, Art. no. 4, Apr. 1979, doi: 10.1121/1.382599.
-[2] P. M. Peterson, “Simulating the response of multiple microphones to a single acoustic source in a reverberant room,” The Journal of the Acoustical Society of America, vol. 80, no. 5, Art. no. 5, Nov. 1986, doi: 10.1121/1.394357.
-[3] E. De Sena, N. Antonello, M. Moonen, and T. van Waterschoot, “On the Modeling of Rectangular Geometries in Room Acoustic Simulations,” IEEE/ACM Transactions on Audio, Speech, and Language Processing, vol. 23, no. 4, Art. no. 4, Apr. 2015, doi: 10.1109/TASLP.2015.2405476.
-[4] F. Brinkmann, V. Erbes, and S. Weinzierl, “Extending the closed form image source model for source directivity,” presented at the DAGA 2018, Munich, Germany, Mar. 2018.
-"""
-function ISM!(
-    h::AbstractVector{T},
-    tx::TxRx,
-    rx::TxRx,
-    room::RectangularRoom,
-    config::ISMConfig;
-) where {T<:AbstractFloat}
-
-    # Number of samples in impulse response
-    Nh = length(h)
-
-    # Samples to distance coefficient [m]
-    Γ = room.c / config.fs
-
-    # Transform size of the room from meters to samples
-    Lₛ = room.L ./ Γ
-
-    # Impulse parameters
-    Δt = 1 / config.fs
-    ω = 2π / config.Wd
-    twid = π * config.fs
-
-    # Compute maximal wall reflection
-    N = ceil.(Int, Nh ./ (2 .* Lₛ))
-
-    o_min, o_max = config.order
-
-    # Main loop
-    for n = -N[1]:N[1], l = -N[2]:N[2], m = -N[3]:N[3]
-        r = (n, l, m)       # Wall reflection indicator
-        Rr = 2 .* r .* room.L    # Wall lattice
-        for q ∈ 0:1, j ∈ 0:1, k ∈ 0:1
-            p = @SVector [q, j, k] # Permutation tuple
-
-            # Order of reflection generated by image source
-            o = sum(abs.(2 .* r .- p))
-
-            if o_min <= o && (o <= o_max || o_max == -1)
-                # Compute Rp part
-                Rp = @. (1 - 2p) * tx.position - rx.position
-
-                # image source position for given permutation
-                isp = Rp .+ Rr
-
-                if config.isd > 0.0 && o > 0
-                    # generate random displacement for the image source
-                    isp .+= randn(config.lrng) * config.isd
-                end
-
-                # Distance between receiver and image source
-                d = norm(isp)
-
-                # Propagation time between receiver and image source
-                τ = d / room.c
-
-                if τ <= Nh / config.fs # Check if it still in transfer function rangΩ
-
-                    # Compute value of reflection coefficients
-                    b = @. room.β ^ abs((n - q, n, l - j, l, m - k, m))
-
-                    # Direction of Arrival of ray incoming from image source to receiver
-                    rx_DoA = isp ./ d
-
-                    # Compute receiver directivity gain
-                    rx_DG = directivity_pattern(SVector{3}(rx_DoA), rx.B, rx.directivity)
-
-                    # Direction of Arrival of ray coming out from transmitter to wall
-                    perm = (abs(n - q) + abs(n), abs(l - j) + abs(l), abs(m - k) + abs(m))
-                    tx_DoA = @. -rx_DoA * (-1, -1, -1)^perm
-
-                    # Compute transmitter directivity gain
-                    tx_DG = directivity_pattern(SVector{3}(tx_DoA), tx.B, tx.directivity)
-
-                    # Compute attenuation coefficient
-                    A = tx_DG * rx_DG * prod(b) / (4π * d)
-
-                    # Compute range of samples in transfer function
-                    i_s = max(ceil(Int, (τ - config.Wd / 2) * config.fs) + 1, 1)  # start
-                    i_e = min(floor(Int, (τ + config.Wd / 2) * config.fs) + 1, Nh) # end
-
-                    # Insert yet another impulse into transfer function
-                    for i ∈ i_s:i_e
-                        t = (i - 1) * Δt - τ # time signature
-                        w = fma(cos_fast(ω*t), 0.5, 0.5) # Hann window
-                        x = twid * t
-                        sinc = ifelse(iszero(x), 1.0,  sin_fast(x)/x)
-                        @inbounds h[i] +=  w * A * sinc
-                    end
-                end
-            end
-        end
-    end
-end
-
 
 function image_source_generator(
     tx::TxRx,
@@ -175,7 +73,6 @@ function image_source_generator(
 
     o_min, o_max = config.order
 
-    # Main loop
     return (begin
         r = (n, l, m)       # Wall reflection indicator
         Rr = 2 .* r .* room.L    # Wall lattice
@@ -229,7 +126,15 @@ function image_source_generator(
     end for n = -N[1]:N[1], l = -N[2]:N[2], m = -N[3]:N[3], q ∈ 0:1, j ∈ 0:1, k ∈ 0:1)
 end
 
-function ISM_slower!(
+
+"""
+References:
+[1] J. B. Allen and D. A. Berkley, “Image method for efficiently simulating small‐room acoustics,” The Journal of the Acoustical Society of America, vol. 65, no. 4, Art. no. 4, Apr. 1979, doi: 10.1121/1.382599.
+[2] P. M. Peterson, “Simulating the response of multiple microphones to a single acoustic source in a reverberant room,” The Journal of the Acoustical Society of America, vol. 80, no. 5, Art. no. 5, Nov. 1986, doi: 10.1121/1.394357.
+[3] E. De Sena, N. Antonello, M. Moonen, and T. van Waterschoot, “On the Modeling of Rectangular Geometries in Room Acoustic Simulations,” IEEE/ACM Transactions on Audio, Speech, and Language Processing, vol. 23, no. 4, Art. no. 4, Apr. 2015, doi: 10.1109/TASLP.2015.2405476.
+[4] F. Brinkmann, V. Erbes, and S. Weinzierl, “Extending the closed form image source model for source directivity,” presented at the DAGA 2018, Munich, Germany, Mar. 2018.
+"""
+function ISM!(
     h::AbstractVector{T},
     tx::TxRx,
     rx::TxRx,
@@ -243,7 +148,8 @@ function ISM_slower!(
     twid = π * config.fs
 
     for a in image_source_generator(tx, rx, room, config)
-        if nothing !== a
+        a |> isnothing && continue
+
         A, τ, _, _ = a
         # Compute range of samples in transfer function
         i_s = max(ceil(Int, (τ - config.Wd / 2) * config.fs) + 1, 1)  # start
@@ -259,5 +165,4 @@ function ISM_slower!(
         end
     end
 end
-end