func OpenStream(inOpts *InputOptions,
outOpts *OutputOptions,
sampleRate float64) (strm *Stream, err error) {
// initialize return value first
strm = new(Stream)
strm.inopts = inOpts
strm.outopts = outOpts
// initialize in and out
var _inopts *C.PaStreamParameters
var _outopts *C.PaStreamParameters
if inOpts != nil {
_inopts = new(C.PaStreamParameters)
_inopts.device = C.Pa_GetDefaultInputDevice()
if inOpts.DeviceID != DefaultDevice {
_inopts.device = C.PaDeviceIndex(inOpts.DeviceID)
}
_inopts.channelCount = C.int(inOpts.ChannelCnt)
_inopts.sampleFormat = C.paFloat32
_inopts.suggestedLatency = C.Pa_GetDeviceInfo(_inopts.device).defaultHighInputLatency
_inopts.hostApiSpecificStreamInfo = nil
}
if outOpts != nil {
_outopts = new(C.PaStreamParameters)
_outopts.device = C.Pa_GetDefaultOutputDevice()
if outOpts.DeviceID != DefaultDevice {
_outopts.device = C.PaDeviceIndex(outOpts.DeviceID)
}
_outopts.channelCount = C.int(outOpts.ChannelCnt)
_outopts.sampleFormat = C.paFloat32
_outopts.suggestedLatency = C.Pa_GetDeviceInfo(_outopts.device).defaultHighOutputLatency
_outopts.hostApiSpecificStreamInfo = nil
}
cerr := C.Pa_OpenStream(
&strm.cee,
_inopts,
_outopts,
C.double(sampleRate),
C.paClipOff,
0,
nil,
nil,
)
if cerr != C.paNoError {
err = errors.New(C.GoString(C.Pa_GetErrorText(cerr)))
return
}
cerr = C.Pa_StartStream(strm.cee)
if cerr != C.paNoError {
err = errors.New(C.GoString(C.Pa_GetErrorText(cerr)))
return
}
return
}
func hostsAndDevices() ([]*HostApiInfo, []*DeviceInfo, error) {
if !cached {
nhosts := C.Pa_GetHostApiCount()
ndevs := C.Pa_GetDeviceCount()
if nhosts < 0 {
return nil, nil, newError(C.PaError(nhosts))
}
if ndevs < 0 {
return nil, nil, newError(C.PaError(ndevs))
}
devices = make([]*DeviceInfo, ndevs)
hosti := make([]C.PaHostApiIndex, ndevs)
for i := range devices {
i := C.PaDeviceIndex(i)
paDev := C.Pa_GetDeviceInfo(i)
devices[i] = &DeviceInfo{
index: i,
Name: C.GoString(paDev.name),
MaxInputChannels: int(paDev.maxInputChannels),
MaxOutputChannels: int(paDev.maxOutputChannels),
DefaultLowInputLatency: duration(paDev.defaultLowInputLatency),
DefaultLowOutputLatency: duration(paDev.defaultLowOutputLatency),
DefaultHighInputLatency: duration(paDev.defaultHighInputLatency),
DefaultHighOutputLatency: duration(paDev.defaultHighOutputLatency),
DefaultSampleRate: float64(paDev.defaultSampleRate),
}
hosti[i] = paDev.hostApi
}
hostApis = make([]*HostApiInfo, nhosts)
for i := range hostApis {
i := C.PaHostApiIndex(i)
paHost := C.Pa_GetHostApiInfo(i)
devs := make([]*DeviceInfo, paHost.deviceCount)
for j := range devs {
devs[j] = devices[C.Pa_HostApiDeviceIndexToDeviceIndex(i, C.int(j))]
}
hostApis[i] = &HostApiInfo{
Type: HostApiType(paHost._type),
Name: C.GoString(paHost.name),
DefaultInputDevice: lookupDevice(devices, paHost.defaultInputDevice),
DefaultOutputDevice: lookupDevice(devices, paHost.defaultOutputDevice),
Devices: devs,
}
}
for i := range devices {
devices[i].HostApi = hostApis[hosti[i]]
}
cached = true
}
return hostApis, devices, nil
}