/**
* Copyright 2007 DFKI GmbH.
* All Rights Reserved. Use is subject to license terms.
*
* This file is part of MARY TTS.
*
* MARY TTS is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, version 3 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*/
package marytts.signalproc.filter;
import java.io.File;
import java.io.IOException;
import java.util.Arrays;
import javax.sound.sampled.AudioFileFormat;
import javax.sound.sampled.AudioFormat;
import javax.sound.sampled.AudioInputStream;
import javax.sound.sampled.AudioSystem;
import javax.sound.sampled.UnsupportedAudioFileException;
import marytts.util.data.BufferedDoubleDataSource;
import marytts.util.data.audio.AudioDoubleDataSource;
import marytts.util.data.audio.DDSAudioInputStream;
import marytts.util.signal.SignalProcUtils;
/**
* This is a simple FIR bandpass filterbank structure with no resampling operations The filters are overlapping and a simple
* DFT-based frequency response estimation method is used for reducing reconstruction error due to non-ideal filtering scheme and
* overlap among filters Given a sampling rate and a set of lower and upper cutoff frequency values in Hz, a set of bandpass
* filters that overlap by some amount in frequency
*
* @author Oytun Türk
*/
public class FIRBandPassFilterBankAnalyser extends FilterBankAnalyserBase {
public static final double OVERLAP_AROUND_1000HZ_DEFAULT = 100.0;
public double overlapAround1000Hz;
public int samplingRateInHz;
public FIRFilter[] filters;
public double[] normalizationFilterTransformedIR;
public double[] lowerCutOffsInHz;
public double[] upperCutOffsInHz;
public FIRBandPassFilterBankAnalyser(int numBands, int samplingRateInHz) {
this(numBands, samplingRateInHz, OVERLAP_AROUND_1000HZ_DEFAULT);
}
public FIRBandPassFilterBankAnalyser(int numBands, int samplingRateInHzIn, double overlapAround1000HzIn) {
samplingRateInHz = samplingRateInHzIn;
double halfSamplingRate = 0.5 * samplingRateInHz;
lowerCutOffsInHz = new double[numBands];
upperCutOffsInHz = new double[numBands];
double overlapInHz;
int i;
overlapAround1000Hz = overlapAround1000HzIn;
for (i = 0; i < numBands; i++) {
if (i < numBands - 1)
upperCutOffsInHz[i] = samplingRateInHz / Math.pow(2, numBands - i);
else
upperCutOffsInHz[i] = halfSamplingRate;
if (i == 0)
lowerCutOffsInHz[i] = 0.0;
else
lowerCutOffsInHz[i] = upperCutOffsInHz[i - 1];
overlapInHz = 0.5 * (upperCutOffsInHz[i] + lowerCutOffsInHz[i]) / (1000.0 / overlapAround1000Hz);
if (i > 0)
lowerCutOffsInHz[i] -= overlapInHz;
if (i < numBands - 1)
upperCutOffsInHz[i] += overlapInHz;
System.out.println("Subband #" + String.valueOf(i + 1) + " - Lower cutoff: " + String.valueOf(lowerCutOffsInHz[i])
+ " Upper cutoff: " + String.valueOf(upperCutOffsInHz[i]));
}
initialise(lowerCutOffsInHz, upperCutOffsInHz, overlapAround1000HzIn);
}
public FIRBandPassFilterBankAnalyser(double[] lowerCutOffsInHzIn, double[] upperCutOffsInHzIn, int samplingRateInHzIn) {
this(lowerCutOffsInHzIn, upperCutOffsInHzIn, samplingRateInHzIn, OVERLAP_AROUND_1000HZ_DEFAULT);
}
public FIRBandPassFilterBankAnalyser(double[] lowerCutOffsInHzIn, double[] upperCutOffsInHzIn, int samplingRateInHzIn,
double overlapAround1000HzIn) {
samplingRateInHz = samplingRateInHzIn;
initialise(lowerCutOffsInHzIn, upperCutOffsInHzIn, overlapAround1000HzIn);
}
public void initialise(double[] lowerCutOffsInHzIn, double[] upperCutOffsInHzIn, double overlapAround1000HzIn) {
normalizationFilterTransformedIR = null;
if (lowerCutOffsInHzIn != null && upperCutOffsInHzIn != null) {
assert lowerCutOffsInHzIn.length == upperCutOffsInHzIn.length;
lowerCutOffsInHz = new double[lowerCutOffsInHzIn.length];
upperCutOffsInHz = new double[upperCutOffsInHzIn.length];
System.arraycopy(lowerCutOffsInHzIn, 0, lowerCutOffsInHz, 0, lowerCutOffsInHzIn.length);
System.arraycopy(upperCutOffsInHzIn, 0, upperCutOffsInHz, 0, upperCutOffsInHzIn.length);
int i;
filters = new FIRFilter[lowerCutOffsInHz.length];
int filterOrder = SignalProcUtils.getFIRFilterOrder(samplingRateInHz);
double normalizedLowerCutoff;
double normalizedUpperCutoff;
overlapAround1000Hz = overlapAround1000HzIn;
for (i = 0; i < lowerCutOffsInHz.length; i++)
assert lowerCutOffsInHz[i] < upperCutOffsInHz[i];
for (i = 0; i < lowerCutOffsInHz.length; i++) {
if (lowerCutOffsInHz[i] <= 0.0) {
normalizedUpperCutoff = Math.min(upperCutOffsInHz[i] / samplingRateInHz, 0.5);
normalizedUpperCutoff = Math.max(normalizedUpperCutoff, 0.0);
filters[i] = new LowPassFilter(normalizedUpperCutoff, filterOrder);
} else if (upperCutOffsInHz[i] >= 0.5 * samplingRateInHz) {
normalizedLowerCutoff = Math.max(lowerCutOffsInHz[i] / samplingRateInHz, 0.0);
normalizedLowerCutoff = Math.min(normalizedLowerCutoff, 0.5);
filters[i] = new HighPassFilter(normalizedLowerCutoff, filterOrder);
} else {
normalizedLowerCutoff = Math.max(lowerCutOffsInHz[i] / samplingRateInHz, 0.0);
normalizedLowerCutoff = Math.min(normalizedLowerCutoff, 0.5);
normalizedUpperCutoff = Math.min(upperCutOffsInHz[i] / samplingRateInHz, 0.5);
normalizedUpperCutoff = Math.max(normalizedUpperCutoff, 0.0);
assert normalizedLowerCutoff < normalizedUpperCutoff;
filters[i] = new BandPassFilter(normalizedLowerCutoff, normalizedUpperCutoff, filterOrder);
}
}
int maxFreq = filters[0].transformedIR.length / 2 + 1;
// Estimate a smooth gain normalization filter
normalizationFilterTransformedIR = new double[maxFreq];
Arrays.fill(normalizationFilterTransformedIR, 0.0);
int j;
for (i = 0; i < filters.length; i++) {
normalizationFilterTransformedIR[0] += Math.abs(filters[i].transformedIR[0]);
normalizationFilterTransformedIR[maxFreq - 1] += Math.abs(filters[i].transformedIR[1]);
for (j = 1; j < maxFreq - 1; j++)
normalizationFilterTransformedIR[j] += Math.sqrt(filters[i].transformedIR[2 * j]
* filters[i].transformedIR[2 * j] + filters[i].transformedIR[2 * j + 1]
* filters[i].transformedIR[2 * j + 1]);
}
for (j = 0; j < maxFreq; j++)
normalizationFilterTransformedIR[j] = 1.0 / normalizationFilterTransformedIR[j];
// MaryUtils.plot(normalizationFilterTransformedIR, "Normalization filter");
//
}
}
public Subband[] apply(double[] x) {
Subband[] subbands = null;
if (filters != null && x != null) {
int i;
subbands = new Subband[filters.length];
for (i = 0; i < filters.length; i++) {
if (filters[i] instanceof LowPassFilter)
subbands[i] = new Subband(filters[i].apply(x), samplingRateInHz, 0.0,
((LowPassFilter) filters[i]).normalisedCutoffFrequency * samplingRateInHz);
else if (filters[i] instanceof HighPassFilter)
subbands[i] = new Subband(filters[i].apply(x), samplingRateInHz,
((HighPassFilter) filters[i]).normalisedCutoffFrequency * samplingRateInHz, 0.5 * samplingRateInHz);
else if (filters[i] instanceof BandPassFilter)
subbands[i] = new Subband(filters[i].apply(x), samplingRateInHz,
((BandPassFilter) filters[i]).lowerNormalisedCutoffFrequency * samplingRateInHz,
((BandPassFilter) filters[i]).upperNormalisedCutoffFrequency * samplingRateInHz);
}
}
//
return subbands;
}
public static void main(String[] args) throws UnsupportedAudioFileException, IOException {
AudioInputStream inputAudio = AudioSystem.getAudioInputStream(new File(args[0]));
int samplingRate = (int) inputAudio.getFormat().getSampleRate();
AudioDoubleDataSource signal = new AudioDoubleDataSource(inputAudio);
double[] x = signal.getAllData();
int i;
int numBands = 4;
double overlapAround1000Hz = 100.0;
FIRBandPassFilterBankAnalyser analyser = new FIRBandPassFilterBankAnalyser(numBands, samplingRate, overlapAround1000Hz);
Subband[] subbands = analyser.apply(x);
DDSAudioInputStream outputAudio;
AudioFormat outputFormat;
String outFileName;
// Write highpass components 0 to numLevels-1
for (i = 0; i < subbands.length; i++) {
outputFormat = new AudioFormat((int) (subbands[i].samplingRate), inputAudio.getFormat().getSampleSizeInBits(),
inputAudio.getFormat().getChannels(), true, true);
outputAudio = new DDSAudioInputStream(new BufferedDoubleDataSource(subbands[i].waveform), outputFormat);
outFileName = args[0].substring(0, args[0].length() - 4) + "_band" + String.valueOf(i + 1) + ".wav";
AudioSystem.write(outputAudio, AudioFileFormat.Type.WAVE, new File(outFileName));
}
}
}