{under,over}flow errors

[bjarthur]

i get an error when trying to simultaneously read and write as described here:

julia> using PortAudio

julia> N = 48000*5
240000

julia> output = randn(N) * 0.1;

julia> input = PortAudioStream(1,1) do str
           @async write(str, output)
           read(str, N)
       end
┌ Warning: libportaudio: Output underflowed
└ @ PortAudio ~/.julia/packages/PortAudio/HNBv4/src/PortAudio.jl:99
┌ Warning: libportaudio: Input overflowed
└ @ PortAudio ~/.julia/packages/PortAudio/HNBv4/src/PortAudio.jl:99
^CERROR: TaskFailedException

Stacktrace

Stacktrace: [1] wait @ ./task.jl:352 [inlined] [2] fetch_messenger(messenger::PortAudio.Messenger{Float32, PortAudio.SampledSignalsReader, Tuple{…}, Int64}, task::Task) @ PortAudio ~/.julia/packages/PortAudio/HNBv4/src/PortAudio.jl:525 [3] close(stream::PortAudioStream{PortAudio.Messenger{…}, PortAudio.Messenger{…}}) @ PortAudio ~/.julia/packages/PortAudio/HNBv4/src/PortAudio.jl:896 [4] PortAudioStream(::var"#1#3", ::Int64, ::Vararg{Int64}; keywords::@kwargs{}) @ PortAudio ~/.julia/packages/PortAudio/HNBv4/src/PortAudio.jl:888 [5] PortAudioStream(::Function, ::Int64, ::Vararg{Int64}) @ PortAudio ~/.julia/packages/PortAudio/HNBv4/src/PortAudio.jl:883 [6] top-level scope @ REPL[8]:1

nested task error: InterruptException:
Stacktrace:
  [1] (::Base.var"#_unlock#648")(rl::ReentrantLock)
    @ Base ./lock.jl:177
  [2] unlock
    @ ./lock.jl:177 [inlined]
  [3] lock(f::PortAudio.var"#7#8"{typeof(PortAudio.LibPortAudio.Pa_ReadStream), Ptr{…}, Matrix{…}, Int64}, l::ReentrantLock)
    @ Base ./lock.jl:231
  [4] #read_or_write#6
    @ ~/.julia/packages/PortAudio/HNBv4/src/PortAudio.jl:245 [inlined]
  [5] read_or_write
    @ ~/.julia/packages/PortAudio/HNBv4/src/PortAudio.jl:233 [inlined]
  [6] #read_buffer!#13
    @ ~/.julia/packages/PortAudio/HNBv4/src/PortAudio.jl:434 [inlined]
  [7] read_buffer!
    @ ~/.julia/packages/PortAudio/HNBv4/src/PortAudio.jl:433 [inlined]
  [8] full_read!
    @ ~/.julia/packages/PortAudio/HNBv4/src/PortAudio.jl:365 [inlined]
  [9] #9
    @ ~/.julia/packages/PortAudio/HNBv4/src/PortAudio.jl:329 [inlined]
 [10] foreach(f::PortAudio.var"#9#10"{…}, itr::StepRange{…})
    @ Base ./abstractarray.jl:3097
 [11] split_up(buffer::PortAudio.Buffer{…}, julia_buffer::Matrix{…}, already::Int64, frame_count::Int64, whole_function::Function, partial_function::typeof(PortAudio.partial_read!))
    @ PortAudio ~/.julia/packages/PortAudio/HNBv4/src/PortAudio.jl:329
 [12] SampledSignalsReader
    @ ~/.julia/packages/PortAudio/HNBv4/src/PortAudio.jl:375 [inlined]
 [13] send(messenger::PortAudio.Messenger{Float32, PortAudio.SampledSignalsReader, Tuple{Matrix{…}, Int64, Int64}, Int64})
    @ PortAudio ~/.julia/packages/PortAudio/HNBv4/src/PortAudio.jl:470
 [14] (::PortAudio.var"#14#15"{PortAudio.Messenger{Float32, PortAudio.SampledSignalsReader, Tuple{…}, Int64}})()
    @ PortAudio ~/.julia/packages/PortAudio/HNBv4/src/PortAudio.jl:505

caused by: TaskFailedException
Stacktrace:
[1] try_yieldto(undo::typeof(Base.ensure_rescheduled))
@ Base ./task.jl:931
[2] wait()
@ Base ./task.jl:995
[3] wait(c::Base.GenericCondition{ReentrantLock}; first::Bool)
@ Base ./condition.jl:130
[4] wait
@ ./condition.jl:125 [inlined]
[5] take_unbuffered(c::Channel{Int64})
@ Base ./channels.jl:494
[6] take!
@ ./channels.jl:471 [inlined]
[7] exchange
@ ~/.julia/packages/PortAudio/HNBv4/src/PortAudio.jl:1031 [inlined]
[8] unsafe_read!
@ ~/.julia/packages/PortAudio/HNBv4/src/PortAudio.jl:1053 [inlined]
[9] read!(source::PortAudio.PortAudioSource{…}, buf::SampledSignals.SampleBuf{…}, n::Int64)
@ SampledSignals ~/.julia/packages/SampledSignals/KYg5Q/src/SampleStream.jl:184
[10] read!
@ ~/.julia/packages/SampledSignals/KYg5Q/src/SampleStream.jl:222 [inlined]
[11] read
@ ~/.julia/packages/SampledSignals/KYg5Q/src/SampleStream.jl:63 [inlined]
[12] read(stream::PortAudioStream{PortAudio.Messenger{…}, PortAudio.Messenger{…}}, arguments::Int64)
@ PortAudio ~/.julia/packages/PortAudio/HNBv4/src/PortAudio.jl:928
[13] (::var"#1#3")(str::PortAudioStream{PortAudio.Messenger{…}, PortAudio.Messenger{…}})
@ Main ./REPL[8]:3
[14] PortAudioStream(::var"#1#3", ::Int64, ::Vararg{Int64}; keywords::@kwargs{})
@ PortAudio ~/.julia/packages/PortAudio/HNBv4/src/PortAudio.jl:886
[15] PortAudioStream(::Function, ::Int64, ::Vararg{Int64})
@ PortAudio ~/.julia/packages/PortAudio/HNBv4/src/PortAudio.jl:883
[16] top-level scope
@ REPL[8]:1

nested task error: InterruptException:
Stacktrace:
  [1] (::Base.var"#_unlock#648")(rl::ReentrantLock)
    @ Base ./lock.jl:177
  [2] unlock
    @ ./lock.jl:177 [inlined]
  [3] lock(f::PortAudio.var"#7#8"{typeof(PortAudio.LibPortAudio.Pa_ReadStream), Ptr{…}, Matrix{…}, Int64}, l::ReentrantLock)
    @ Base ./lock.jl:231
  [4] #read_or_write#6
    @ ~/.julia/packages/PortAudio/HNBv4/src/PortAudio.jl:245 [inlined]
  [5] read_or_write
    @ ~/.julia/packages/PortAudio/HNBv4/src/PortAudio.jl:233 [inlined]
  [6] #read_buffer!#13
    @ ~/.julia/packages/PortAudio/HNBv4/src/PortAudio.jl:434 [inlined]
  [7] read_buffer!
    @ ~/.julia/packages/PortAudio/HNBv4/src/PortAudio.jl:433 [inlined]
  [8] full_read!
    @ ~/.julia/packages/PortAudio/HNBv4/src/PortAudio.jl:365 [inlined]
  [9] #9
    @ ~/.julia/packages/PortAudio/HNBv4/src/PortAudio.jl:329 [inlined]
 [10] foreach(f::PortAudio.var"#9#10"{…}, itr::StepRange{…})
    @ Base ./abstractarray.jl:3097
 [11] split_up(buffer::PortAudio.Buffer{…}, julia_buffer::Matrix{…}, already::Int64, frame_count::Int64, whole_function::Function, partial_function::typeof(PortAudio.partial_read!))
    @ PortAudio ~/.julia/packages/PortAudio/HNBv4/src/PortAudio.jl:329
 [12] SampledSignalsReader
    @ ~/.julia/packages/PortAudio/HNBv4/src/PortAudio.jl:375 [inlined]
 [13] send(messenger::PortAudio.Messenger{Float32, PortAudio.SampledSignalsReader, Tuple{Matrix{…}, Int64, Int64}, Int64})
    @ PortAudio ~/.julia/packages/PortAudio/HNBv4/src/PortAudio.jl:470
 [14] (::PortAudio.var"#14#15"{PortAudio.Messenger{Float32, PortAudio.SampledSignalsReader, Tuple{…}, Int64}})()
    @ PortAudio ~/.julia/packages/PortAudio/HNBv4/src/PortAudio.jl:505

Some type information was truncated. Use show(err) to see complete types.

same story when just trying to read as described in the docs:

julia> using PortAudio

julia> stream = PortAudioStream(1,0)
PortAudioStream{Float32}
  Samplerate: 48000Hz
  1 channel source: "MacBook Pro Microphone"

julia> buf = read(stream, 10)
┌ Warning: libportaudio: Input overflowed
└ @ PortAudio ~/.julia/packages/PortAudio/HNBv4/src/PortAudio.jl:99
10-frame, 1-channel SampleBuf{Float32, 2}
0.00020833333333333335s sampled at 48000.0Hz
▂▃▃▃▃▃▃▃▃▃

ditto for just playing, though it actually did play something:

julia> using PortAudio, SampledSignals

julia> S = 8192 # sampling rate (samples / second)
8192

julia> x = cos.(2pi*(1:2S)*440/S) # A440 tone for 2 seconds
16384-element Vector{Float64}:

julia> PortAudioStream(0, 2; samplerate=S) do stream
           write(stream, x)
       end
┌ Warning: libportaudio: Output underflowed
└ @ PortAudio ~/.julia/packages/PortAudio/HNBv4/src/PortAudio.jl:99
16384

julia> versioninfo()
Julia Version 1.10.2
Commit bd47eca2c8a (2024-03-01 10:14 UTC)
Build Info:
  Official https://julialang.org/ release
Platform Info:
  OS: macOS (arm64-apple-darwin22.4.0)
  CPU: 12 × Apple M2 Max
  WORD_SIZE: 64
  LIBM: libopenlibm
  LLVM: libLLVM-15.0.7 (ORCJIT, apple-m1)
Threads: 1 default, 0 interactive, 1 GC (on 8 virtual cores)
Environment:
  JULIA_PROJECT = @.
  JULIA_EDITOR = vi

(jl_0map0x) pkg> st
Status `/private/var/folders/s5/8d629n5d7nsf37f60_91wzr40000gq/T/jl_0map0x/Project.toml`
  [80ea8bcb] PortAudio v1.3.0

[mashu]

I was getting the very same warning, when I played audio like this

stream = PortAudioStream(0, 1)
write(stream, SampleBuf(audio, 44100))
close(stream)

and when audio was Vector{Float64} after changing that input to Vector{Float32} the underflow warning is gone.
Hopefully this helps to narrow down and fix the issue?