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wip: adds filter viewer JavaFX utility application for visualizing

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filters designed through the filter factory.
This commit is contained in:
denny
2016-04-11 19:22:56 -04:00
parent 3231e9828b
commit 097884337b
13 changed files with 1100 additions and 56 deletions
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44
src/dsp/filter/FilterFactory.java
View File

@@ -1,6 +1,6 @@
/*******************************************************************************
* SDR Trunk
* Copyright (C) 2014,2015 Dennis Sheirer
* Copyright (C) 2014-2016,2015 Dennis Sheirer
*
* Root Raised Cosine filter designer:
* Copyright 2002,2007,2008,2012,2013 Free Software Foundation, Inc.
@@ -35,9 +35,46 @@ import dsp.filter.cic.ComplexPrimeCICDecimate;
public class FilterFactory
{
private final static Logger mLog =
LoggerFactory.getLogger( FilterFactory.class );
private final static Logger mLog = LoggerFactory.getLogger( FilterFactory.class );
public static final double TWO_PI = Math.pow( Math.PI, 2.0 );
public static float[] getNewLowPass( int sampleRate, long passFrequency, long stopFrequency,
int attenuation, WindowType window )
{
assert( passFrequency <= sampleRate / 2 );
int length = getTapCount( sampleRate, passFrequency, stopFrequency, attenuation );
if( length % 2 == 0 )
{
length++;
}
float[] coefficients = new float[ length ];
int half = length / 2;
int K = (int)( length * ( 2.0d * (double)passFrequency / (double) sampleRate ));
double scale = 1.0 / (double)length;
coefficients[ half ] = (float)( K / (double)length );
for( int k = 1; k <= half; k++ )
{
float coefficient = (float)( scale * ( Math.sin( Math.PI * k * K / length ) /
Math.sin( Math.PI * k / length ) ) );
coefficients[ k + half ] = coefficient;
coefficients[ half - k ] = coefficient;
}
Window.apply( WindowType.HANNING, coefficients );
return coefficients;
}
/**
* Generates coefficients for a unity-gain, windowed low-pass filter
* @param sampleRate - hertz
@@ -78,6 +115,7 @@ public class FilterFactory
}
//Apply the window against the coefficients
coefficients = Window.apply( window, coefficients );
//Normalize to unity (1) gain

2
src/dsp/filter/GoertzelFilter.java
View File

@@ -32,7 +32,7 @@ public class GoertzelFilter
private int mSampleRate;
private long mTargetFrequency;
private int mBlockSize;
private double[] mWindowCoefficients;
private float[] mWindowCoefficients;
private double mCoefficient;

87
src/dsp/filter/Window.java
View File

@@ -19,6 +19,9 @@ package dsp.filter;
import java.util.Arrays;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Window creator
*
@@ -33,7 +36,9 @@ import java.util.Arrays;
*/
public class Window
{
public static double[] getWindow( WindowType type, int length )
private final static Logger mLog = LoggerFactory.getLogger( Window.class );
public static float[] getWindow( WindowType type, int length )
{
switch( type )
{
@@ -51,18 +56,18 @@ public class Window
}
}
public static double[] getRectangularWindow( int length )
public static float[] getRectangularWindow( int length )
{
double[] coefficients = new double[ length ];
float[] coefficients = new float[ length ];
Arrays.fill( coefficients, 1.0d );
Arrays.fill( coefficients, 1.0f );
return coefficients;
}
public static double[] getCosineWindow( int length )
public static float[] getCosineWindow( int length )
{
double[] coefficients = new double[ length ];
float[] coefficients = new float[ length ];
if( length % 2 == 0 ) //Even length
@@ -71,7 +76,7 @@ public class Window
for( int x = -half; x < length / 2 + 1; x++ )
{
coefficients[ x + half ] = Math.cos(
coefficients[ x + half ] = (float)Math.cos(
( (double)x * Math.PI ) / ( (double)length + 1.0d ) );
}
}
@@ -81,7 +86,7 @@ public class Window
for( int x = -half; x < half + 1; x++ )
{
coefficients[ x + half ] = Math.cos(
coefficients[ x + half ] = (float)Math.cos(
( (double)x * Math.PI ) / ( (double)length + 1.0d ) );
}
}
@@ -89,62 +94,62 @@ public class Window
return coefficients;
}
public static double[] getBlackmanWindow( int length )
public static float[] getBlackmanWindow( int length )
{
double[] coefficients = new double[ length ];
float[] coefficients = new float[ length ];
for( int x = 0; x < length; x++ )
{
coefficients[ x ] = .426591D -
coefficients[ x ] = (float)( .426591D -
( .496561D * Math.cos( ( Math.PI * 2.0D * (double)x ) / (double)( length - 1 ) ) +
( .076848D * Math.cos( ( Math.PI * 4.0D * (double)x ) / (double)( length - 1 ) ) ) );
( .076848D * Math.cos( ( Math.PI * 4.0D * (double)x ) / (double)( length - 1 ) ) ) ) );
}
return coefficients;
}
public static double[] getHammingWindow( int length )
public static float[] getHammingWindow( int length )
{
double[] coefficients = new double[ length ];
float[] coefficients = new float[ length ];
if( length % 2 == 0 ) //Even length
{
for( int x = 0; x < length; x++ )
{
coefficients[ x ] = .54D - ( .46D *
Math.cos( ( Math.PI * ( 2.0D * (double)x + 1.0d ) ) / (double)( length - 1 ) ) );
coefficients[ x ] = (float)( .54D - ( .46D *
Math.cos( ( Math.PI * ( 2.0D * (double)x + 1.0d ) ) / (double)( length - 1 ) ) ) );
}
}
else //Odd length
{
for( int x = 0; x < length; x++ )
{
coefficients[ x ] = .54D - ( .46D *
Math.cos( ( 2.0D * Math.PI * (double)x ) / (double)( length - 1 ) ) );
coefficients[ x ] = (float)( .54D - ( .46D *
Math.cos( ( 2.0D * Math.PI * (double)x ) / (double)( length - 1 ) ) ) );
}
}
return coefficients;
}
public static double[] getHanningWindow( int length )
public static float[] getHanningWindow( int length )
{
double[] coefficients = new double[ length ];
float[] coefficients = new float[ length ];
if( length % 2 == 0 ) //Even length
{
for( int x = 0; x < length; x++ )
{
coefficients[ x ] = .5D - ( .5D *
Math.cos( ( Math.PI * ( 2.0D * (double)x + 1 ) ) / (double)( length - 1 ) ) );
coefficients[ x ] = (float)( .5D - ( .5D *
Math.cos( ( Math.PI * ( 2.0D * (double)x + 1 ) ) / (double)( length - 1 ) ) ) );
}
}
else //Odd length
{
for( int x = 0; x < length; x++ )
{
coefficients[ x ] = .5D - ( .5D *
Math.cos( ( 2.0D * Math.PI * (double)x ) / (double)( length - 1 ) ) );
coefficients[ x ] = (float)( .5D - ( .5D *
Math.cos( ( 2.0D * Math.PI * (double)x ) / (double)( length - 1 ) ) ) );
}
}
@@ -155,41 +160,21 @@ public class Window
/**
* Apply the window against an array of float-type samples
*/
public static float[] apply( double[] coefficients, float[] samples )
public static float[] apply( float[] windowCoefficients, float[] samples )
{
for( int x = 0; x < coefficients.length; x++ )
for( int x = 0; x < windowCoefficients.length; x++ )
{
samples[ x ] = (float)( samples[ x ] * coefficients[ x ] );
samples[ x ] = samples[ x ] * windowCoefficients[ x ];
}
return samples;
}
public static float[] apply( WindowType type, float[] samples )
{
double[] coefficients = getWindow( type, samples.length );
float[] windowCoefficients = getWindow( type, samples.length );
return apply( coefficients, samples );
}
/**
* Apply the window against an array of float-type samples
*/
public static double[] apply( double[] coefficients, double[] samples )
{
for( int x = 0; x < coefficients.length; x++ )
{
samples[ x ] = samples[ x ] * coefficients[ x ];
}
return samples;
}
public static double[] apply( WindowType type, double[] samples )
{
double[] coefficients = getWindow( type, samples.length );
return apply( coefficients, samples );
return apply( windowCoefficients, samples );
}
@@ -205,7 +190,7 @@ public class Window
/**
* Utility to log the double arrays
*/
public static String arrayToString( double[] array, boolean breaks )
public static String arrayToString( float[] array, boolean breaks )
{
StringBuilder sb = new StringBuilder();
for( int x = 0; x < array.length; x++ )