comparison dsp/tempotracking/TempoTrackV2.cpp @ 281:33e03341d541

* Make it possible to retrieve beat spectral difference function from
  bar detector
* Avoid crashes when bar detector is run with very short input

     // matrix to store output of comb filter bank, increment column of matrix at each frame
     d_mat_t rcfmat;
     int col_counter = -1;
 
     // main loop for beat period calculation
-    for (uint i=0; i<(df.size()-winlen); i+=step)
+    for (uint i=0; i+winlen<df.size(); i+=step)
     {
         // get dfframe
         d_vec_t dfframe(winlen);
         for (uint k=0; k<winlen; k++)
         {

         }
     }
 
 
     uint T = delta.size();
+
+    if (T < 2) return; // can't do anything at all meaningful
+
     uint Q = delta[0].size();
 
     // initialize first column of delta
     for (uint j=0; j<Q; j++)
     {

 
 void
 TempoTrackV2::calculateBeats(const d_vec_t &df, const d_vec_t &beat_period,
                              d_vec_t &beats)
 {
+    if (df.empty() || beat_period.empty()) return;
+
     d_vec_t cumscore(df.size()); // store cumulative score
     i_vec_t backlink(df.size()); // backlink (stores best beat locations at each time instant)
     d_vec_t localscore(df.size()); // localscore, for now this is the same as the detection function
 
     for (uint i=0; i<df.size(); i++)

     {
         tmp_vec.push_back(cumscore[i]);
     }  
 
     int startpoint = get_max_ind(tmp_vec) + cumscore.size() - beat_period[beat_period.size()-1] ;
+
+    // can happen if no results obtained earlier (e.g. input too short)
+    if (startpoint >= backlink.size()) startpoint = backlink.size()-1;
 
     // USE BACKLINK TO GET EACH NEW BEAT (TOWARDS THE BEGINNING OF THE FILE)
     //  BACKTRACKING FROM THE END TO THE BEGINNING.. MAKING SURE NOT TO GO BEFORE SAMPLE 0
     i_vec_t ibeats;
     ibeats.push_back(startpoint);
     std::cerr << "startpoint = " << startpoint << std::endl;
     while (backlink[ibeats.back()] > 0)
     {
         std::cerr << "backlink[" << ibeats.back() << "] = " << backlink[ibeats.back()] << std::endl;
-        ibeats.push_back(backlink[ibeats.back()]);
+        int b = ibeats.back();
+        if (backlink[b] == b) break; // shouldn't happen... haha
+        ibeats.push_back(backlink[b]);
     }
   
     // REVERSE SEQUENCE OF IBEATS AND STORE AS BEATS
     for (uint i=0; i<ibeats.size(); i++)
     {