`save("sound.wav", buf)` seems to write with the wrong samplerate

[anandijain]

using PortAudio, SampledSignals, LibSndFile, FileIO, Test
devs = PortAudio.devices()
mic = PortAudioStream("MacBook Pro Microphone", 1, 0)
buf = read(mic, 2s)
close(mic)
save("data/grooovin2.wav", buf)
w, sr = wavread("data/grooovin2.wav")
@test buf.samplerate == 48000
@test sr == 8000

WAV.jl is able to write it fine. I haven't dug in to locate the issue though

env info

(SipSynth) pkg> st
     Project SipSynth v0.1.0
      Status `~/.julia/dev/SipSynth/Project.toml`
  [5789e2e9] FileIO v1.11.1
  [b13ce0c6] LibSndFile v2.4.0
  [f57c4921] MIDI v2.0.2
  [80ea8bcb] PortAudio v1.1.2
  [003e8c73] RtMIDI v0.1.0 `../RtMIDI#main`
  [bd7594eb] SampledSignals v2.1.2
  [2d7b7beb] libportaudio_jll v19.7.0+0 `https://github.com/anandijain/libportaudio_jll.jl#main`
  [5bf562c0] libsndfile_jll v1.0.31+0 `https://github.com/anandijain/libsndfile_jll.jl#main`

julia> versioninfo()
Julia Version 1.7.0-rc1
Commit 9eade6195e (2021-09-12 06:45 UTC)
Platform Info:
  OS: macOS (arm64-apple-darwin20.5.0)
  CPU: Apple M1
  WORD_SIZE: 64
  LIBM: libopenlibm
  LLVM: libLLVM-12.0.1 (ORCJIT, cyclone)
Environment:
  JULIA_NUM_THREADS = 8

see JuliaAudio/PortAudio.jl#88

[rob-luke]

I dont think SampledSignals provides the function save, I used the GitHub search and the word save doesn't appear in this repository at all. So I think this is probably an issue with whatever library is providing the save or read functionality.

But also, I ran the following code and it created a file with the correct sample rate, so maybe the issue is with your wavread function

using PortAudio, LibSndFile, FileIO, SampledSignals
mic = PortAudioStream("Unknown USB Audio Device", 1, 0)
buf = read(mic, 2s)
> 96000-frame, 1-channel SampleBuf{Float32, 2}
> 2.0s sampled at 48000.0Hz
save("grooovin2.wav", buf)
> I then open this with audition and it has a correct 48kHz sample rate