void
ARThread::OnPreflight( const SignalProperties& Input,
SignalProperties& Output ) const
{
if( Input.Elements() < Parameter( "ModelOrder" ) )
bcierr << "WindowLength parameter must be large enough"
<< " for the number of samples to exceed the model order"
<< endl;
if( Parameter( "OutputType" ) == Coefficients )
{
Output = Input;
Output.SetName( "AR Coefficients" );
Output.SetElements( Parameter( "ModelOrder" ) );
Output.ElementUnit().SetSymbol( "" )
.SetOffset( 0 )
.SetGain( 1 )
.SetRawMin( 0 )
.SetRawMax( Output.Elements() - 1 );
}
else
{
SpectrumThread::OnPreflight( Input, Output );
Output.SetName( "AR " + Output.Name() );
}
}
void
FFTFilter::DetermineSignalProperties( SignalProperties& ioProperties, int inFFTType ) const
{
int numChannels = Parameter( "FFTInputChannels" )->NumValues(),
fftWindowLength = static_cast<int>( ioProperties.Elements() * Parameter( "FFTWindowLength" ).InSampleBlocks() );
if( numChannels > 0 && fftWindowLength == 0 )
bcierr << "FFTWindowLength must exceed a single sample's duration" << endl;
double freqRange = ioProperties.SamplingRate() / 2.0;
switch( inFFTType )
{
case eInput:
break;
case ePower:
{
ioProperties.SetName( "FFT Power Spectrum" )
.SetChannels( numChannels )
.SetElements( fftWindowLength / 2 + 1 );
ioProperties.ElementUnit().SetOffset( 0.0 )
.SetGain( freqRange / ( ioProperties.Elements() - 1 ) )
.SetSymbol( "Hz" );
double amplitude = ioProperties.ValueUnit().RawMax() - ioProperties.ValueUnit().RawMin();
ioProperties.ValueUnit().SetRawMin( 0 )
.SetRawMax( amplitude * amplitude );
ioProperties.ElementUnit().SetRawMin( 0 )
.SetRawMax( ioProperties.Elements() - 1 );
} break;
case eHalfcomplex:
ioProperties.SetName( "FFT Coefficients" )
.SetChannels( numChannels )
.SetElements( fftWindowLength );
ioProperties.ElementUnit().SetRawMin( 0 )
.SetRawMax( fftWindowLength - 1 )
.SetOffset( 0 )
.SetGain( 1 )
.SetSymbol( "" );
break;
default:
throw std_logic_error( "Unknown value of FFT type" );
}
}
void
FFTFilter::DetermineSignalProperties( SignalProperties& ioProperties, int inFFTType ) const
{
int numChannels = Parameter( "FFTInputChannels" )->NumValues(),
fftWindowLength = Parameter( "SampleBlockSize" )
* MeasurementUnits::ReadAsTime( Parameter( "FFTWindowLength" ) );
if( numChannels > 0 && fftWindowLength == 0 )
bcierr << "FFTWindowLength must exceed a single sample's duration" << endl;
switch( inFFTType )
{
case eInput:
break;
case ePower:
{
ioProperties.SetName( "FFT Power Spectrum" )
.SetChannels( numChannels )
.SetElements( fftWindowLength / 2 + 1 );
float freqScale = Parameter( "SamplingRate" ) / 2.0 / ioProperties.Elements();
ioProperties.ElementUnit().SetOffset( freqScale / 2 )
.SetGain( freqScale )
.SetSymbol( "Hz" );
float amplitude = ioProperties.ValueUnit().RawMax() - ioProperties.ValueUnit().RawMin();
ioProperties.ValueUnit().SetRawMin( 0 )
.SetRawMax( amplitude * amplitude );
} break;
case eHalfcomplex:
ioProperties.SetName( "FFT Coefficients" )
.SetChannels( numChannels )
.SetElements( fftWindowLength );
break;
default:
assert( false );
}
}
void
ARFilter::Preflight( const SignalProperties& Input,
SignalProperties& Output ) const
{
// Parameter consistency checks.
float windowLength = MeasurementUnits::ReadAsTime( Parameter( "WindowLength" ) );
int samplesInWindow = windowLength * Parameter( "SampleBlockSize" );
if( samplesInWindow < Parameter( "ModelOrder" ) )
bcierr << "WindowLength parameter must be large enough"
<< " for the number of samples to exceed the model order"
<< endl;
Output = Input;
switch( int( Parameter( "OutputType" ) ) )
{
case SpectralAmplitude:
case SpectralPower:
{
float firstBinCenter = MeasurementUnits::ReadAsFreq( Parameter( "FirstBinCenter" ) ),
lastBinCenter = MeasurementUnits::ReadAsFreq( Parameter( "LastBinCenter" ) ),
binWidth = MeasurementUnits::ReadAsFreq( Parameter( "BinWidth" ) );
if( firstBinCenter > 0.5 || firstBinCenter < 0
|| lastBinCenter > 0.5 || lastBinCenter < 0 )
bcierr << "FirstBinCenter and LastBinCenter must be greater zero and"
<< " less than half the sampling rate"
<< endl;
if( firstBinCenter >= lastBinCenter )
bcierr << "FirstBinCenter must be less than LastBinCenter" << endl;
if( binWidth <= 0 )
bcierr << "BinWidth must be greater zero" << endl;
else
{
int numBins = ::floor( ( lastBinCenter - firstBinCenter + eps ) / binWidth + 1 );
Output.SetElements( numBins );
}
Output.ElementUnit().SetOffset( firstBinCenter / binWidth )
.SetGain( binWidth * Parameter( "SamplingRate" ) )
.SetSymbol( "Hz" );
Output.ValueUnit().SetRawMin( 0 );
float inputAmplitude = Input.ValueUnit().RawMax() - Input.ValueUnit().RawMin(),
whiteNoisePowerPerBin = inputAmplitude * inputAmplitude / binWidth / 10;
switch( int( Parameter( "OutputType" ) ) )
{
case SpectralAmplitude:
Output.SetName( "AR Amplitude Spectrum" );
Output.ValueUnit().SetOffset( 0 )
.SetGain( 1e-6 )
.SetSymbol( "V/sqrt(Hz)" )
.SetRawMax( ::sqrt( whiteNoisePowerPerBin ) );
break;
case SpectralPower:
{
Output.SetName( "AR Power Spectrum" );
Output.ValueUnit().SetOffset( 0 )
.SetGain( 1 )
.SetSymbol( "(muV)^2/Hz" )
.SetRawMax( whiteNoisePowerPerBin );
} break;
}
} break;
case ARCoefficients:
Output.SetName( "AR Coefficients" );
Output.SetElements( Parameter( "ModelOrder" ) );
Output.ElementUnit().SetOffset( 0 )
.SetGain( 1 )
.SetSymbol( "" );
Output.ValueUnit().SetOffset( 0 )
.SetGain( 1 )
.SetSymbol( "" )
.SetRawMin( -1 )
.SetRawMax( 1 );
break;
default:
bcierr << "Unknown OutputType" << endl;
}
Output.ElementUnit().SetRawMin( 0 )
.SetRawMax( Output.Elements() - 1 );
}
void
LinearClassifier::Preflight( const SignalProperties& Input,
SignalProperties& Output ) const
{
// Determine the classifier matrix format:
int controlSignalChannels = 0;
const ParamRef& Classifier = Parameter( "Classifier" );
if( Classifier->NumColumns() != 4 )
bcierr << "Classifier parameter must have 4 columns "
<< "(input channel, input element, output channel, weight)"
<< endl;
else
{
for( int row = 0; row < Classifier->NumRows(); ++row )
{
if( Classifier( row, 2 ) < 1 )
bcierr << "Output channels must be positive integers"
<< endl;
float ch = Input.ChannelIndex( Classifier( row, 0 ) );
if( ch < 0 )
bcierr << DescribeEntry( row, 0 )
<< " points to negative input index"
<< endl;
else if( ::floor( ch ) > Input.Channels() )
bcierr << "Channel specification in "
<< DescribeEntry( row, 0 )
<< " exceeds number of input channels"
<< endl;
if( ::fmod( ch, 1.0f ) > 1e-2 )
bciout << "Channel specification in physical units: "
<< DescribeEntry( row, 0 )
<< " does not exactly meet a single channel"
<< endl;
float el = Input.ElementIndex( Classifier( row, 1 ) );
if( el < 0 )
bcierr << DescribeEntry( row, 1 )
<< " points to negative input index"
<< endl;
if( ::floor( el ) > Input.Elements() )
bcierr << "Element (bin) specification in "
<< DescribeEntry( row, 1 )
<< " exceeds number of input elements"
<< endl;
if( ::fmod( el, 1.0f ) > 1e-2 )
bciout << "Element (bin) specification in physical units: "
<< DescribeEntry( row, 1 )
<< " does not exactly meet a single element"
<< endl;
int outputChannel = Classifier( row, 2 );
controlSignalChannels = max( controlSignalChannels, outputChannel );
}
}
// Requested output signal properties.
Output = SignalProperties( controlSignalChannels, 1, Input.Type() );
// Output description.
Output.ChannelUnit() = Input.ChannelUnit();
Output.ValueUnit().SetRawMin( Input.ValueUnit().RawMin() )
.SetRawMax( Input.ValueUnit().RawMax() );
float secsPerBlock = Parameter( "SampleBlockSize" ) / Parameter( "SamplingRate" );
Output.ElementUnit().SetOffset( 0 ).SetGain( secsPerBlock ).SetSymbol( "s" );
int visualizationTime = Output.ElementUnit().PhysicalToRaw( "15s" );
Output.ElementUnit().SetRawMin( 0 ).SetRawMax( visualizationTime - 1 );
}
void
FFTFilter::Initialize( const SignalProperties& Input, const SignalProperties& /*Output*/ )
{
mFFTOutputSignal = ( eFFTOutputSignal )( int )Parameter( "FFTOutputSignal" );
mFFTWindowLength = static_cast<int>( Input.Elements() * Parameter( "FFTWindowLength" ).InSampleBlocks() );
mFFTWindow = ( eFFTWindow )( int )Parameter( "FFTWindow" );
mFFTInputChannels.clear();
for( size_t i = 0; i < mVisualizations.size(); ++i )
mVisualizations[ i ].Send( CfgID::Visible, false );
mVisualizations.clear();
mVisualizeFFT = int( Parameter( "VisualizeFFT" ) );
if( mVisualizeFFT || mFFTOutputSignal == ePower )
{
mVisProperties = Input;
DetermineSignalProperties( mVisProperties, ePower );
PhysicalUnit elementUnit = mVisProperties.ElementUnit();
mVisProperties.SetChannels( mVisProperties.Elements() );
for( int i = 0; i < mVisProperties.Channels(); ++i )
mVisProperties.ChannelLabels()[i] = elementUnit.RawToPhysical( mVisProperties.Channels() - i - 1 );
mVisProperties.SetElements( 1 );
mVisProperties.ElementUnit() = Input.ElementUnit();
mVisProperties.ElementUnit().SetGain( mVisProperties.ElementUnit().Gain() * Input.Elements() );
mPowerSpectrum = GenericSignal( mVisProperties );
}
for( int i = 0; i < Parameter( "FFTInputChannels" )->NumValues(); ++i )
{
size_t ch = static_cast<size_t>( Input.ChannelIndex( Parameter( "FFTInputChannels" )( i ) ) );
mFFTInputChannels.push_back( ch );
if( mVisualizeFFT )
{
ostringstream oss_i;
oss_i << i + 1;
mVisualizations.push_back( GenericVisualization( string( "FFT" ) + oss_i.str() ) );
ostringstream oss_ch;
oss_ch << "FFT for Ch ";
if( Input.ChannelLabels().IsTrivial() )
oss_ch << i + 1;
else
oss_ch << Input.ChannelLabels()[ch];
mVisualizations.back().Send( mVisProperties )
.Send( CfgID::WindowTitle, oss_ch.str().c_str() )
.Send( CfgID::GraphType, CfgID::Field2d )
.Send( CfgID::Visible, true );
}
}
mWindow.clear();
mWindow.resize( mFFTWindowLength, 1.0 );
float phasePerSample = static_cast<float>( M_PI ) / static_cast<float>( mFFTWindowLength );
// Window coefficients: None Hamming Hann Blackman
const float a1[] = { 0, 0.46f, 0.5f, 0.5f, },
a2[] = { 0, 0, 0, 0.08f };
for( int i = 0; i < mFFTWindowLength; ++i )
mWindow[ i ] = 1.0f - a1[ mFFTWindow ] - a2[ mFFTWindow ]
+ a1[ mFFTWindow ] * cos( static_cast<float>( i ) * phasePerSample )
+ a2[ mFFTWindow ] * cos( static_cast<float>( i ) * 2.0f * phasePerSample );
mValueBuffers.resize( mFFTInputChannels.size() );
ResetValueBuffers( mFFTWindowLength );
bool fftRequired = ( mVisualizeFFT || mFFTOutputSignal != eInput)
&& mFFTInputChannels.size() > 0;
if( !fftRequired )
mFFTInputChannels.clear();
else
mFFT.Initialize( mFFTWindowLength );
}
