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[WIP] Updating dsp modules to accept variable sample rate I/Q streams

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and creating a new audio resampler.
This commit is contained in:
Denny
2018-02-09 05:29:07 -05:00
parent 96d9d6f750
commit 28cb9d9407
15 changed files with 369 additions and 171 deletions
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30
src/main/java/io/github/dsheirer/source/tuner/manager/TunerChannelSourceManager.java
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@@ -181,18 +181,39 @@ public class TunerChannelSourceManager extends ChannelSourceManager
long bestIntegralFrequency = getIntegralFrequency(channels);
//See if we can reuse the current frequency
//Strategy 1: reuse the current frequency if it's a good integral and the channels fit
if(isIntegralSpacing(currentCenterFrequency, bestIntegralFrequency) &&
isValidCenterFrequency(channels, currentCenterFrequency))
{
return currentCenterFrequency;
}
//Start by placing the first channel at the minimum location within the tuner bandwidth
double usableHalfBandwidth = mTunerController.getUsableHalfBandwidth();
//Strategy 2: start by placing the center frequency exactly one channel width below the first channel frequency
//and iteratively increase it one channel width at a time. This optimally places the channels nearest to the
//center of the bandwidth
long start = channels.first().getFrequency() - (int)mPolyphaseChannelManager.getChannelBandwidth();
if(isValidCenterFrequency(channels, start))
{
return start;
}
while(start - channels.first().getMinFrequency() < usableHalfBandwidth)
{
start += (int)mPolyphaseChannelManager.getChannelBandwidth();
if(isValidCenterFrequency(channels, start))
{
return start;
}
}
//Strategy 3: start by placing the first channel at the minimum location within the tuner bandwidth
double startFrequency = channels.first().getMinFrequency() + usableHalfBandwidth;
//Align the test frequency to the next greater integral frequency placing to place the first channel at the
//Align the test frequency to the next greater integral frequency placing the first channel at the
// minimum extreme of the available bandwidth as a starting location
double delta = Math.abs(startFrequency - bestIntegralFrequency);
double adjustment = delta % mPolyphaseChannelManager.getChannelBandwidth();
@@ -221,7 +242,8 @@ public class TunerChannelSourceManager extends ChannelSourceManager
currentChannel++;
}
//If we can't find an integral center frequency, choose a frequency that will fit the channels
//Strategy 4: brute force walk across the spectrum 1 hertz at a time looking for a center frequency that will
//fit all channels
long testFrequency = channels.first().getMinFrequency() + mTunerController.getUsableHalfBandwidth();
long minimumFrequency = testFrequency - availableTestBandwidth;