Disable stereo @ <100khz to prevent invalid filters

cjcliffe · Jun 7, 2015 · 95ff1e9 · 95ff1e9
1 parent 25dc28d
commit 95ff1e9
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Showing 3 changed files with 16 additions and 7 deletions.
diff --git a/src/demod/DemodulatorPreThread.cpp b/src/demod/DemodulatorPreThread.cpp
@@ -57,9 +57,13 @@ void DemodulatorPreThread::initialize() {
     firStereoRight = firfilt_rrrf_create(h, h_len);
 
     // stereo pilot filter
+    float bw = params.bandwidth;
+    if (bw < 100000.0) {
+        bw = 100000.0;
+    }
     unsigned int order =   5;       // filter order
-    float        f0    =   ((double) 19000 / (double) params.bandwidth);
-    float        fc    =   ((double) 19500 / (double) params.bandwidth);
+    float        f0    =   ((double) 19000 / bw);
+    float        fc    =   ((double) 19500 / bw);
     float        Ap    =   1.0f;
     As    =  60.0f;
     iirStereoPilot = iirfilt_crcf_create_prototype(LIQUID_IIRDES_CHEBY2, LIQUID_IIRDES_BANDPASS, LIQUID_IIRDES_SOS, order, fc, f0, Ap, As);

diff --git a/src/demod/DemodulatorThread.cpp b/src/demod/DemodulatorThread.cpp
@@ -117,6 +117,7 @@ void DemodulatorThread::threadMain() {
                 ampmodem_reset(demodAM);
             }
             freqdem_reset(demodFM);
+            nco_crcf_reset(stereoPilot);
         }
 
         if (firStereoLeft != inp->firStereoLeft) {
@@ -223,7 +224,7 @@ void DemodulatorThread::threadMain() {
         unsigned int numAudioWritten;
         msresamp_rrrf_execute(audioResampler, &demodOutputData[0], bufSize, &resampledOutputData[0], &numAudioWritten);
 
-        if (stereo) {
+        if (stereo && inp->sampleRate >= 100000) {
             if (demodStereoData.size() != bufSize) {
                 if (demodStereoData.capacity() < bufSize) {
                     demodStereoData.reserve(bufSize);
@@ -302,7 +303,7 @@ void DemodulatorThread::threadMain() {
                 ati->sampleRate = audioSampleRate;
                 ati->setRefCount(1);
 
-                if (stereo) {
+                if (stereo && inp->sampleRate >= 100000) {
                     ati->channels = 2;
                     if (ati->data.capacity() < (numAudioWritten * 2)) {
                         ati->data.reserve(numAudioWritten * 2);
@@ -343,7 +344,7 @@ void DemodulatorThread::threadMain() {
             ati_vis->busy_update.lock();
 
             int num_vis = DEMOD_VIS_SIZE;
-            if (stereo) {
+            if (stereo && inp->sampleRate >= 100000) {
                 ati_vis->channels = 2;
                 int stereoSize = ati->data.size();
                 if (stereoSize > DEMOD_VIS_SIZE) {

diff --git a/src/demod/DemodulatorWorkerThread.cpp b/src/demod/DemodulatorWorkerThread.cpp
@@ -70,10 +70,14 @@ void DemodulatorWorkerThread::threadMain() {
                 result.firStereoLeft = firfilt_rrrf_create(h, h_len);
                 result.firStereoRight = firfilt_rrrf_create(h, h_len);
 
+                float bw = filterCommand.bandwidth;
+                if (bw < 100000.0) {
+                    bw = 100000.0;
+                }
                 // stereo pilot filter
                 unsigned int order =   5;       // filter order
-                float        f0    =   ((double) 19000 / (double) filterCommand.bandwidth);
-                float        fc    =   ((double) 19500 / (double) filterCommand.bandwidth);
+                float        f0    =   ((double) 19000 / bw);
+                float        fc    =   ((double) 19500 / bw);
                 float        Ap    =   1.0f;
                 As    =  60.0f;