mirror of
https://github.com/DSheirer/sdrtrunk.git
synced 2026-11-12 08:37:25 -05:00
e61c3a891c
Converted to use float primitives and to keep samples in buffer format until the sample rate is decimated to 48kHz. Added new non-recursive, CIC decimation filter -- untested Updated sound card/mixer input source management. Now testing for mono/stereo support for each card and limiting channel choices accordingly. Separated the mixersource into a ComplexMixer and and SimplexMixerSource. The ComplexMixer is used for sound card based tuners like the funcube. The SimplexMixerSource is used for demodulated sound card inputs. Interfaces for sample handling - standardized on using 'Complex' to indicate I/Q samples and 'Simplex' to indicate demodulated float samples. The processing chain now accepts either a decimated (48k) list of complex samples from a tuner channel source, or a 48k simplex buffer (array of demodulated float samples). Resolved issue with HackRF tuner not applying tuner configuration information.
58 lines
1.8 KiB
Java
58 lines
1.8 KiB
Java
/*******************************************************************************
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* SDR Trunk
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* Copyright (C) 2014 Dennis Sheirer
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*
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* This program is free software: you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation, either version 3 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program. If not, see <http://www.gnu.org/licenses/>
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******************************************************************************/
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package source.tuner.rtl;
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import sample.adapter.SampleAdapter;
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import sample.complex.ComplexBuffer;
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public class ByteSampleAdapter extends SampleAdapter
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{
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private final static float[] LOOKUP_VALUES;
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/**
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* Creates a static lookup table that converts the 8-bit valued range
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* from 0 - 255 into scaled float values of -32768.0 to 0 to 32512.0
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*/
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static
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{
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LOOKUP_VALUES = new float[ 256 ];
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for( int x = 0; x < 256; x++ )
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{
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LOOKUP_VALUES[ x ] = (float)( x - 128 ) * 256.0f;
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}
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LOOKUP_VALUES[ 128 ] = 0.0000001f;
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}
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@Override
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public float[] convert( byte[] samples )
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{
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float[] convertedSamples = new float[ samples.length ];
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int pointer = 0;
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for( byte sample: samples )
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{
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/* Convert byte value into float from the lookup table */
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convertedSamples[ pointer++ ] = LOOKUP_VALUES[ ( sample & 0xFF ) ];
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}
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return convertedSamples;
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}
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}
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