Some work on resampler delay

Author: cannam

src/finer/R3LiveShifter.cpp

@@ -212,6 +212,10 @@ R3LiveShifter::createResamplers()
     resamplerParameters.maxBufferSize = m_guideConfiguration.longestFftSize;
     resamplerParameters.dynamism = Resampler::RatioOftenChanging;
     resamplerParameters.ratioChange = Resampler::SmoothRatioChange;
+
+    int debug = m_log.getDebugLevel();
+    if (debug > 0) --debug;
+    resamplerParameters.debugLevel = debug;
 
     m_inResampler = std::unique_ptr<Resampler>
         (new Resampler(resamplerParameters, m_parameters.channels));
@@ -235,15 +239,18 @@ R3LiveShifter::getFormantScale() const
 size_t
 R3LiveShifter::getPreferredStartPad() const
 {
-    //!!!???
     return 0;
 }
 
 size_t
 R3LiveShifter::getStartDelay() const
 {
+    //!!! need a principled way - measure it in ctor perhaps
     int resamplerDelay = 32;
-    int fixed = getWindowSourceSize() / 2 + resamplerDelay;
+#ifdef HAVE_LIBSAMPLERATE
+    resamplerDelay = 47;
+#endif
+    int fixed = getWindowSourceSize() / 2 + resamplerDelay * 2;
     int variable = getWindowSourceSize() / 2;
     if (m_contractThenExpand) {
         if (m_pitchScale < 1.0) {
@@ -305,7 +312,6 @@ R3LiveShifter::shift(const float *const *input, float *const *output)
     m_log.log(2, "R3LiveShifter::shift: initially in outbuf", m_channelData[0]->outbuf->getReadSpace());
 
     int pad = 0;
-    int resamplerDelay = 32;
     if (m_firstProcess) {
         if (m_contractThenExpand) {
             pad = getWindowSourceSize();
@@ -315,7 +321,6 @@ R3LiveShifter::shift(const float *const *input, float *const *output)
         } else {
             pad = getWindowSourceSize() / 2;
         }
-        pad += resamplerDelay;
         m_log.log(2, "R3LiveShifter::shift: extending input with pre-pad", incount, pad);
         for (int c = 0; c < m_parameters.channels; ++c) {
             m_channelData[c]->inbuf->zero(pad);
@@ -336,7 +341,7 @@ R3LiveShifter::shift(const float *const *input, float *const *output)
         }
     }
 
-    int requiredInOutbuf = int(ceil(incount / outRatio)) + resamplerDelay;
+    int requiredInOutbuf = int(ceil(incount / outRatio));
     generate(requiredInOutbuf);
 
     int got = readOut(output, incount, 0);
@@ -417,8 +422,18 @@ R3LiveShifter::readIn(const float *const *input)
          incount,
          inRatio,
          false);
-
+    
     m_log.log(2, "R3LiveShifter::readIn: writing to inbuf from resampled data, former read space and samples being added", m_channelData[0]->inbuf->getReadSpace(), resampleOutput);
+
+    if (m_firstProcess) {
+        int expected = floor(incount * inRatio);
+        if (resampleOutput < expected) {
+            m_log.log(2, "R3LiveShifter::readIn: resampler left us short on first process, pre-padding output: expected and obtained", expected, resampleOutput);
+            for (int c = 0; c < m_parameters.channels; ++c) {
+                m_channelData[c]->inbuf->zero(expected - resampleOutput);
+            }
+        }
+    }
 
     for (int c = 0; c < m_parameters.channels; ++c) {
         m_channelData[c]->inbuf->write
@@ -646,7 +661,18 @@ R3LiveShifter::readOut(float *const *output, int outcount, int origin)
     }
 
     if (resampledCount < outcount) {
-        m_log.log(0, "R3LiveShifter::readOut: WARNING: Failed to obtain enough samples from resampler", resampledCount, outcount);
+        if (m_firstProcess) {
+            m_log.log(2, "R3LiveShifter::readOut: resampler left us short on first process, pre-padding output: expected and obtained", outcount, resampledCount);
+            int prepad = outcount - resampledCount;
+            for (int c = 0; c < m_parameters.channels; ++c) {
+                v_move(m_channelAssembly.mixdown.data()[c] + prepad,
+                       m_channelAssembly.mixdown.data()[c], resampledCount);
+                v_zero(m_channelAssembly.mixdown.data()[c], prepad);
+            }
+            resampledCount = outcount;
+        } else {
+            m_log.log(0, "R3LiveShifter::readOut: WARNING: Failed to obtain enough samples from resampler", resampledCount, outcount);
+        }
     }
 
     if (useMidSide()) {

src/finer/R3Stretcher.cpp

@@ -299,6 +299,10 @@ R3Stretcher::createResampler()
         resamplerParameters.dynamism = Resampler::RatioMostlyFixed;
         resamplerParameters.ratioChange = Resampler::SuddenRatioChange;
     }
+
+    int debug = m_log.getDebugLevel();
+    if (debug > 0) --debug;
+    resamplerParameters.debugLevel = debug;
 
     m_resampler = std::unique_ptr<Resampler>
         (new Resampler(resamplerParameters, m_parameters.channels));

src/test/TestLiveShifter.cpp

@@ -52,18 +52,19 @@ BOOST_AUTO_TEST_CASE(sinusoid_unchanged)
     int n = 100000;
     float freq = 440.f;
     int rate = 44100;
+
+    if (printDebug) {
+        RubberBandLiveShifter::setDefaultDebugLevel(2);
+    }
+    
     RubberBandLiveShifter shifter
         (rate, 1, RubberBandLiveShifter::OptionPitchModeB);
 
     //!!!
-    shifter.setPitchScale(2.0);
-    
-    if (printDebug) {
-        shifter.setDebugLevel(2);
-    }
+//    shifter.setPitchScale(2.0);
 
     int blocksize = shifter.getBlockSize();
-    BOOST_TEST(blocksize == 2560);
+    BOOST_TEST(blocksize == 512);
 
     n = (n / blocksize + 1) * blocksize;
 
@@ -79,6 +80,8 @@ BOOST_AUTO_TEST_CASE(sinusoid_unchanged)
     }
 
     int delay = shifter.getStartDelay();
+
+    std::cerr << "delay reported as " << delay << std::endl;    
 
     // We now have n samples of a simple sinusoid with stretch factor
     // 1.0; obviously we expect the output to be essentially the same
@@ -106,18 +109,21 @@ BOOST_AUTO_TEST_CASE(sinusoid_unchanged)
                tt::tolerance(0.001f) << tt::per_element());
 
     if (printDebug) {
-        // The initial # is to allow grep on the test output
-        std::cout << "#sample\tV" << std::endl;
+        // The prefix is to allow grep on the test output
+        
+        std::cout << "IN,sample,V" << std::endl;
+        for (int i = 0; i < int(in.size()); ++i) {
+            std::cout << "IN," << i << "," << in[i] << std::endl;
+        }
+        
+        std::cout << "OUT,sample,V" << std::endl;
         for (int i = 0; i < int(out.size()); ++i) {
-            std::cout << "#" << i << "\t" << out[i] << std::endl;
+            std::cout << "OUT," << i << "," << out[i] << std::endl;
         }
-    }
 
-    if (printDebug) {
-        // The initial @ is to allow grep on the test output
-        std::cout << "@sample\tV" << std::endl;
+        std::cout << "DIFF,V" << std::endl;
         for (int i = 0; i + delay < int(in.size()); ++i) {
-            std::cout << "@" << i << "\t" << out[i + delay] - in[i] << std::endl;
+            std::cout << "DIFF," << i << "," << out[i + delay] - in[i] << std::endl;
         }
     }
 #endif