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nodes.jl
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nodes.jl
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#### NullNode ####
type NullRenderer <: AudioRenderer end
typealias NullNode AudioNode{NullRenderer}
export NullNode
function render(node::NullRenderer, device_input::AudioBuf, info::DeviceInfo)
# TODO: preallocate buffer
return zeros(AudioSample,info.buf_size)
end
#### SinOsc ####
# Generates a sin tone at the given frequency
#the phase-version is a mess: freq is actually a tuple (freq,phase)
type SinOscRenderer{T<:Union(Float32, AudioNode,(Float32,Float32,))} <: AudioRenderer
freq::T
phase::Float32
buf::AudioBuf
function SinOscRenderer(freq)
new(freq, 0.0, AudioSample[])
end
end
typealias SinOsc AudioNode{SinOscRenderer}
SinOsc(freq::Real) = SinOsc(SinOscRenderer{Float32}(freq))
SinOsc(freq::Real,phase::Real) = SinOsc(SinOscRenderer{(Float32,Float32)}((freq,phase)))
SinOsc(freq::AudioNode) = SinOsc(SinOscRenderer{AudioNode}(freq))
SinOsc() = SinOsc(440)
export SinOsc
function render(node::SinOscRenderer{Float32}, device_input::AudioBuf,
info::DeviceInfo)
if length(node.buf) != info.buf_size
resize!(node.buf, info.buf_size)
end
outbuf = node.buf
phase = node.phase
freq = node.freq
# make sure these are Float32s so that we don't allocate doing conversions
# in the tight loop
pi2::Float32 = 2pi
phase_inc::Float32 = 2pi * freq / info.sample_rate
i::Int = 1
while i <= info.buf_size
outbuf[i] = sin(phase)
phase = (phase + phase_inc) % pi2
i += 1
end
node.phase = phase
return outbuf
end
function render(node::SinOscRenderer{(Float32,Float32)}, device_input::AudioBuf,
info::DeviceInfo)
if length(node.buf) != info.buf_size
resize!(node.buf, info.buf_size)
end
outbuf = node.buf
(freq,phi) = node.freq
phase = float32(( ( 2pi * freq * info.sample/info.sample_rate ) +phi)% 2pi )
err = min(abs(phase-node.phase), 2pi - abs(phase-node.phase))
if( err > 2pi/1e5) warn("Phase Noise: $(err)") end
# make sure these are Float32s so that we don't allocate doing conversions
# in the tight loop
pi2::Float32 = 2pi
phase_inc::Float32 = 2pi * freq / info.sample_rate
i::Int = 1
while i <= info.buf_size
outbuf[i] = sin(phase)
phase = (phase + phase_inc) % pi2
i += 1
end
node.phase = phase
return outbuf
end
function render(node::SinOscRenderer{AudioNode}, device_input::AudioBuf,
info::DeviceInfo)
freq = render(node.freq, device_input, info)::AudioBuf
block_size = min(length(freq), info.buf_size)
if(length(node.buf) != block_size)
resize!(node.buf, block_size)
end
outbuf = node.buf
phase::Float32 = node.phase
pi2::Float32 = 2pi
phase_step::Float32 = 2pi/(info.sample_rate)
i::Int = 1
while i <= block_size
outbuf[i] = sin(phase)
phase = (phase + phase_step*freq[i]) % pi2
i += 1
end
node.phase = phase
return outbuf
end
#### AudioMixer ####
# Mixes a set of inputs equally
type MixRenderer <: AudioRenderer
inputs::Vector{AudioNode}
buf::AudioBuf
MixRenderer(inputs) = new(inputs, AudioSample[])
MixRenderer() = MixRenderer(AudioNode[])
end
typealias AudioMixer AudioNode{MixRenderer}
export AudioMixer
function render(node::MixRenderer, device_input::AudioBuf, info::DeviceInfo)
if length(node.buf) != info.buf_size
resize!(node.buf, info.buf_size)
end
mix_buffer = node.buf
n_inputs = length(node.inputs)
i = 1
max_samples = 0
fill!(mix_buffer, 0)
while i <= n_inputs
rendered = render(node.inputs[i], device_input, info)::AudioBuf
nsamples = length(rendered)
max_samples = max(max_samples, nsamples)
j::Int = 1
while j <= nsamples
mix_buffer[j] += rendered[j]
j += 1
end
if nsamples < info.buf_size
deleteat!(node.inputs, i)
n_inputs -= 1
else
i += 1
end
end
if max_samples < length(mix_buffer)
return mix_buffer[1:max_samples]
else
# save the allocate and copy if we don't need to
return mix_buffer
end
end
Base.push!(mixer::AudioMixer, node::AudioNode) = push!(mixer.renderer.inputs, node)
#### Gain ####
type GainRenderer{T<:Union(Float32, AudioNode)} <: AudioRenderer
in1::AudioNode
in2::T
buf::AudioBuf
GainRenderer(in1, in2) = new(in1, in2, AudioSample[])
end
function render(node::GainRenderer{Float32},
device_input::AudioBuf,
info::DeviceInfo)
input = render(node.in1, device_input, info)::AudioBuf
if length(node.buf) != length(input)
resize!(node.buf, length(input))
end
i = 1
while i <= length(input)
node.buf[i] = input[i] * node.in2
i += 1
end
return node.buf
end
function render(node::GainRenderer{AudioNode},
device_input::AudioBuf,
info::DeviceInfo)
in1_data = render(node.in1, device_input, info)::AudioBuf
in2_data = render(node.in2, device_input, info)::AudioBuf
block_size = min(length(in1_data), length(in2_data))
if length(node.buf) != block_size
resize!(node.buf, block_size)
end
i = 1
while i <= block_size
node.buf[i] = in1_data[i] * in2_data[i]
i += 1
end
return node.buf
end
typealias Gain AudioNode{GainRenderer}
Gain(in1::AudioNode, in2::Real) = Gain(GainRenderer{Float32}(in1, in2))
Gain(in1::AudioNode, in2::AudioNode) = Gain(GainRenderer{AudioNode}(in1, in2))
export Gain
#### Offset ####
type OffsetRenderer <: AudioRenderer
in_node::AudioNode
offset::Float32
buf::AudioBuf
OffsetRenderer(in_node, offset) = new(in_node, offset, AudioSample[])
end
function render(node::OffsetRenderer, device_input::AudioBuf, info::DeviceInfo)
input = render(node.in_node, device_input, info)::AudioBuf
if length(node.buf) != length(input)
resize!(node.buf, length(input))
end
i = 1
while i <= length(input)
node.buf[i] = input[i] + node.offset
i += 1
end
return node.buf
end
typealias Offset AudioNode{OffsetRenderer}
export Offset
#### Array Player ####
# Plays a AudioBuf by rendering it out piece-by-piece
type ArrayRenderer <: AudioRenderer
arr::AudioBuf
arr_index::Int
buf::AudioBuf
ArrayRenderer(arr::AudioBuf) = new(arr, 1, AudioSample[])
end
typealias ArrayPlayer AudioNode{ArrayRenderer}
export ArrayPlayer
function render(node::ArrayRenderer, device_input::AudioBuf, info::DeviceInfo)
range_end = min(node.arr_index + info.buf_size-1, length(node.arr))
block_size = range_end - node.arr_index + 1
if length(node.buf) != block_size
resize!(node.buf, block_size)
end
copy!(node.buf, 1, node.arr, node.arr_index, block_size)
node.arr_index = range_end + 1
return node.buf
end
# Allow users to play a raw array by wrapping it in an ArrayPlayer
function play(arr::AudioBuf, args...)
player = ArrayPlayer(arr)
play(player, args...)
end
# If the array is the wrong floating type, convert it
function play{T <: FloatingPoint}(arr::Array{T}, args...)
arr = convert(AudioBuf, arr)
play(arr, args...)
end
# If the array is an integer type, scale to [-1, 1] floating point
# integer audio can be slightly (by 1) more negative than positive,
# so we just scale so that +/- typemax(T) becomes +/- 1
function play{T <: Signed}(arr::Array{T}, args...)
arr = arr / typemax(T)
play(arr, args...)
end
function play{T <: Unsigned}(arr::Array{T}, args...)
zero = (typemax(T) + 1) / 2
range = floor(typemax(T) / 2)
arr = (arr .- zero) / range
play(arr, args...)
end
#### Noise ####
type WhiteNoiseRenderer <: AudioRenderer end
typealias WhiteNoise AudioNode{WhiteNoiseRenderer}
export WhiteNoise
function render(node::WhiteNoiseRenderer, device_input::AudioBuf, info::DeviceInfo)
return rand(AudioSample, info.buf_size) .* 2 .- 1
end
#### AudioInput ####
# Renders incoming audio input from the hardware
type InputRenderer <: AudioRenderer
channel::Int
InputRenderer(channel::Integer) = new(channel)
InputRenderer() = new(1)
end
function render(node::InputRenderer, device_input::AudioBuf, info::DeviceInfo)
@assert size(device_input, 1) == info.buf_size
return device_input[:, node.channel]
end
typealias AudioInput AudioNode{InputRenderer}
export AudioInput
# Renders incoming audio input from the hardware
#for some reason, it requires something to be playing already, that isn't all 0.0s
type PullToPullRenderer <: AudioRenderer
new_buf::Condition
buf::AudioBuf
dummy_buf::AudioBuf
old::Bool
PullToPullRenderer() = new(Condition(),AudioSample[],AudioSample[],true)
end
function render(node::PullToPullRenderer, device_input::AudioBuf, info::DeviceInfo)
#println("PTPR id: $(object_id(node)), s: $(info.sample)")
@assert size(device_input, 1) == info.buf_size #should handle smaller input buffers too.
if length(node.dummy_buf) != info.buf_size
resize!(node.dummy_buf,info.buf_size)
node.dummy_buf[:] = 0
end
@assert all(node.dummy_buf .== 0 ) #check, for now, whether someone tampered with our output buffer
if length(node.buf) != length(device_input)
resize!(node.buf,length(device_input))
end
copy!(node.buf,1,device_input,1,length(device_input))
node.old=false
#println("PTPR id: $(object_id(node)) trigger notify")
notify(node.new_buf)
return node.dummy_buf
end
typealias PullToPull AudioNode{PullToPullRenderer}
export PullToPull
type PullToPullRendererOut <: AudioRenderer
other::PullToPull
n_sent::Int64
PullToPullRendererOut(other::PullToPull) = new(other,0)
end
function render(node::PullToPullRendererOut, device_input::AudioBuf, info::DeviceInfo)
n::PullToPullRenderer = node.other.renderer
println("PTPRO id: $(hex(object_id(node))), s: $(info.sample)")
if node.n_sent <= -1 #some bug. if we ever return dummy buf, then this render function never gets called again
node.n_sent += 1
return n.dummy_buf
end
if n.old
wait(n.new_buf)
@assert n.old == false
n.old = true
end
println("\tPTPRO id: $(hex(object_id(node))), s: $(info.sample)")
node.n_sent += 1
return n.buf
end
typealias PullToPullOut AudioNode{PullToPullRendererOut}
export PullToPullOut
#### LinRamp ####
type LinRampRenderer <: AudioRenderer
key_samples::Array{AudioSample}
key_durations::Array{Float32}
duration::Float32
buf::AudioBuf
LinRampRenderer(start, finish, dur) = LinRampRenderer([start,finish], [dur])
LinRampRenderer(key_samples, key_durations) =
LinRampRenderer(
[convert(AudioSample,s) for s in key_samples],
[convert(Float32,d) for d in key_durations]
)
function LinRampRenderer(key_samples::Array{AudioSample}, key_durations::Array{Float32})
@assert length(key_samples) == length(key_durations) + 1
new(key_samples, key_durations, sum(key_durations), AudioSample[])
end
end
typealias LinRamp AudioNode{LinRampRenderer}
export LinRamp
function render(node::LinRampRenderer, device_input::AudioBuf, info::DeviceInfo)
# Resize buffer if (1) it's too small or (2) we've hit the end of the ramp
ramp_samples::Int = int(node.duration * info.sample_rate)
block_samples = min(ramp_samples, info.buf_size)
if length(node.buf) != block_samples
resize!(node.buf, block_samples)
end
# Fill the buffer as long as there are more segments
dt::Float32 = 1/info.sample_rate
i::Int = 1
while i <= length(node.buf) && length(node.key_samples) > 1
# Fill as much of the buffer as we can with the current segment
ds::Float32 = (node.key_samples[2] - node.key_samples[1]) / node.key_durations[1] / info.sample_rate
while i <= length(node.buf)
node.buf[i] = node.key_samples[1]
node.key_samples[1] += ds
node.key_durations[1] -= dt
node.duration -= dt
i += 1
# Discard segment if we're finished
if node.key_durations[1] <= 0
if length(node.key_durations) > 1
node.key_durations[2] -= node.key_durations[1]
end
shift!(node.key_samples)
shift!(node.key_durations)
break
end
end
end
return node.buf
end
type MemorylessNodeRenderer <: AudioRenderer
f::Function
buf::AudioBuf
function MemorylessNodeRenderer(f::Function)
new(f,AudioSample[])
end
end
function render(node::MemorylessNodeRenderer,input::AudioBuf,info::DeviceInfo)
@assert size(input, 1) <= info.buf_size
if length(node.buf) != size(input, 1)
resize!(node.buf, size(input, 1))
end
output = node.buf
i::Int = 1
while i <= length(node.buf)
output[i] = node.f(input[i])
i += 1
end
return output
end
typealias MemorylessNode AudioNode{MemorylessNodeRenderer}
export MemorylessNode
type ArrayRecorderRenderer <: AudioRenderer
arr::AudioBuf
arr_index::Int
buf::AudioBuf
ArrayRecorderRenderer(arr::AudioBuf) = new(arr, 1, AudioSample[])
end
typealias ArrayRecorderNode AudioNode{ArrayRecorderRenderer}
export ArrayRecorderNode
function render(node::ArrayRecorderRenderer, input::AudioBuf, info::DeviceInfo)
@assert size(input, 1) <= info.buf_size
range_end = min(node.arr_index + size(input, 1)-1, length(node.arr))
block_size = range_end - node.arr_index + 1
if length(node.buf) != block_size
resize!(node.buf, block_size)
node.buf[:] = 0
end
copy!(node.arr,node.arr_index,input,1,block_size)
node.arr_index = range_end + 1
if node.arr_index == length(node.arr)
return AudioSample[] #return an array of small size to signal that this node is done
end
return node.buf
end
type ComposeNodeRenderer <: AudioRenderer
first::AudioNode
second::AudioNode
buf::AudioBuf
#input to ComposeNode first goes through first, then second, then that is output.
ComposeNodeRenderer(first::AudioNode,second::AudioNode) = new(first, second, AudioSample[])
end
typealias ComposeNode AudioNode{ComposeNodeRenderer}
export ComposeNode
function render(node::ComposeNodeRenderer, input::AudioBuf, info::DeviceInfo)
@assert size(input, 1) <= info.buf_size #might get an incomplete buffer
first = node.first
second = node.second
out1 = render(first,input,info)
out2 = render(second,out1,info)
@assert size(out2,1) <= info.buf_size
block_size = size(out2,1)
if length(node.buf) != block_size
resize!(node.buf, block_size)
end
copy!(node.buf,1,out2,1,block_size)
return node.buf
end
type DelayMixRenderer <: AudioRenderer
delay::Int
buf::AudioBuf
buf_last_in::AudioBuf
#output[n] = input[n] * input[n-delay]
DelayMixRenderer(delay::Integer) = new(delay, AudioSample[], AudioSample[])
end
typealias DelayMixNode AudioNode{DelayMixRenderer}
export DelayMixNode
function render(node::DelayMixRenderer, input::AudioBuf, info::DeviceInfo)
@assert size(input, 1) <= info.buf_size #might get an incomplete buffer
@assert node.delay <= info.buf_size #otherwise need to store more buffers
if length(node.buf_last_in) == 0
resize!(node.buf_last_in,info.buf_size)
node.buf_last_in[:] = 0
end
if length(node.buf) != size(input, 1)
resize!(node.buf, size(input, 1))
end
for i=1:min(node.delay,length(input))
v = input[i] * node.buf_last_in[end-node.delay + i ]
node.buf[i] = v
end
if length(input)>node.delay
for i=node.delay+1:length(input)
node.buf[i] = input[i] * input[i-node.delay]
end
end
if length(node.buf_last_in) == 0
resize!(node.buf_last_in,info.buf_size)
end
resize!(node.buf_last_in,length(input))
copy!(node.buf_last_in,1,input,1,length(input))
return node.buf
end
import Multirate: FIRFilter, filt!, firdes, outputlength, FIRResponse, LOWPASS, HIGHPASS
type FSK_IQ_DemodRenderer <: AudioRenderer
buf::AudioBuf
buf1::AudioBuf
buf2::AudioBuf
buf3::AudioBuf
buf4::AudioBuf
buf1o::AudioBuf
buf2o::AudioBuf
buf3o::AudioBuf
buf4o::AudioBuf
filt1::FIRFilter
filt2::FIRFilter
filt3::FIRFilter
filt4::FIRFilter
function FSK_IQ_DemodRenderer()
h = firdes( 200, .2 * 200, samplerate = 41000, response = LOWPASS )
f1 = FIRFilter(h)
f2 = FIRFilter(h)
f3 = FIRFilter(h)
f4 = FIRFilter(h)
new(AudioSample[],AudioSample[],AudioSample[],AudioSample[],AudioSample[],
AudioSample[],AudioSample[],AudioSample[],AudioSample[],f1,f2,f3,f4)
end
end
typealias FSK_IQ_DemodNode AudioNode{FSK_IQ_DemodRenderer}
export FSK_IQ_DemodNode
function render(node::FSK_IQ_DemodRenderer, input::AudioBuf, info::DeviceInfo)
@assert size(input, 1) <= info.buf_size #might get an incomplete buffer
if length(node.buf) != length(input)
resize!(node.buf,length(input))
resize!(node.buf1,length(input))
resize!(node.buf2,length(input))
resize!(node.buf3,length(input))
resize!(node.buf4,length(input))
end
if length(node.buf1o) != outputlength( node.filt1, length( input ) )
resize!(node.buf1o,length(input))
resize!(node.buf2o,length(input))
resize!(node.buf3o,length(input))
resize!(node.buf4o,length(input))
end
f_h = float32(2pi*1800 / info.sample_rate)
f_l = float32(2pi*1400 / info.sample_rate)
s = info.sample-1
for i=1:length(input)
node.buf1[i] = cos(f_h * (i+s) ) * input[i]
node.buf2[i] = sin(f_h * (i+s) ) * input[i]
node.buf3[i] = cos(f_l * (i+s) ) * input[i]
node.buf4[i] = sin(f_l * (i+s) ) * input[i]
end
filt!( node.buf1o, node.filt1, node.buf1 )
filt!( node.buf2o, node.filt2, node.buf2 )
filt!( node.buf3o, node.filt3, node.buf3 )
filt!( node.buf4o, node.filt4, node.buf4 )
for i=1:length(input)
node.buf1o[i] = sqrt(node.buf1o[i]^2 + node.buf2o[i]^2)
node.buf3o[i] = sqrt(node.buf3o[i]^2 + node.buf4o[i]^2)
node.buf[i] = node.buf3o[i] - node.buf1o[i]
end
return node.buf
end
type NormalizerRenderer <: AudioRenderer
window::Int
buf::AudioBuf
buf_history::AudioBuf
NormalizerRenderer(window::Int) = new(window, AudioSample[], AudioSample[])
end
typealias NormalizerNode AudioNode{NormalizerRenderer}
export NormalizerNode
function render(node::NormalizerRenderer, input::AudioBuf, info::DeviceInfo)
@assert size(input, 1) <= info.buf_size #might get an incomplete buffer
if length(node.buf_history) != node.window
resize!(node.buf_history,node.window)
node.buf_history[:] = 0
end
if length(node.buf) != size(input, 1)
resize!(node.buf, size(input, 1))
end
#shift buffer over
shift_over = length(input)
for i=1:(length(node.buf_history)-shift_over)
node.buf_history[i] = node.buf_history[i+shift_over]
end
copy!(node.buf_history,length(node.buf_history)-shift_over+1,input,1,shift_over)
for i=1:length(input)
m = median(node.buf_history[i:i+node.window-length(input)])
node.buf[i] = input[i] - m
end
return node.buf
end
type MovingAverageRenderer <: AudioRenderer
window::Int
buf::AudioBuf
ring_history::AudioBuf
ring_history_idx::Int
MovingAverageRenderer(window::Int) = new(window, AudioSample[], AudioSample[], 1,)
end
typealias MovingAverageNode AudioNode{MovingAverageRenderer}
export MovingAverageNode
function render(node::MovingAverageRenderer, input::AudioBuf, info::DeviceInfo)
@assert size(input, 1) <= info.buf_size #might get an incomplete buffer
if length(node.ring_history) != node.window
resize!(node.ring_history,node.window)
node.ring_history[:] = 0
end
if length(node.buf) != size(input, 1)
resize!(node.buf, size(input, 1))
end
for i=1:length(input)
node.ring_history[node.ring_history_idx] = input[i]
node.ring_history_idx = ((node.ring_history_idx+1) % node.window) + 1
node.buf[i] = max(node.ring_history) + min(node.ring_history)
end
return node.buf
end