cannam@0: /* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */
cannam@0: 
cannam@0: /*
cannam@0:     Vamp feature extraction plugin using the MATCH audio alignment
cannam@0:     algorithm.
cannam@0: 
cannam@0:     Centre for Digital Music, Queen Mary, University of London.
Chris@236:     Copyright (c) 2007-2020 Simon Dixon, Chris Cannam, and Queen Mary
Chris@230:     University of London, Copyright (c) 2014-2015 Tido GmbH.
cannam@0:     
cannam@0:     This program is free software; you can redistribute it and/or
cannam@0:     modify it under the terms of the GNU General Public License as
cannam@0:     published by the Free Software Foundation; either version 2 of the
cannam@0:     License, or (at your option) any later version.  See the file
cannam@0:     COPYING included with this distribution for more information.
cannam@0: */
cannam@0: 
cannam@0: #include "Path.h"
cannam@0: 
cannam@0: int
cannam@0: Path::smooth(std::vector<int> &x, std::vector<int> &y, int length)
cannam@0: {
Chris@188:     if (length <= 0)
cannam@0:         return 0;
Chris@188:     while (m_val.size() < static_cast<std::vector<int>::size_type>(length)) {
Chris@188:         m_val.push_back(0);
Chris@188:         m_len.push_back(0);
cannam@0:     }
cannam@0:     int p = 0;
Chris@188:     m_val[0] = m_len[0] = 0;
cannam@0:     for (int i = 1; i < length; i++) {	// H = 1; V = 2; D = 3
cannam@0:         int current = x[i] - x[i-1] + 2 * (y[i] - y[i-1]);
Chris@188:         if (current == m_val[p]) {
Chris@188:             m_len[p]++;
Chris@188:         } else if ((current == 3) || (m_val[p] == 0)) {
Chris@188:             m_val[++p] = current;
Chris@188:             m_len[p] = 1;
Chris@188:         } else if (m_val[p] + current == 3) {	// 1 + 2
Chris@188:             if (--m_len[p] == 0)
cannam@0:                 p--;
Chris@188:             if (m_val[p] == 3)
Chris@188:                 m_len[p]++;
cannam@0:             else {
Chris@188:                 m_val[++p] = 3;
Chris@188:                 m_len[p] = 1;
cannam@0:             }
Chris@188:         } else {	// m_val[p] == 3 && current != 3
Chris@188:             if ((m_val[p-1] == current) ||
Chris@188:                 (m_val[p-1] == 0) ||
Chris@188:                 (m_len[p] > MAX_RUN_LENGTH)) {
Chris@188:                 m_val[++p] = current;
Chris@188:                 m_len[p] = 1;
cannam@0:             } else {
Chris@188:                 if (--m_len[p-1] == 0) {
Chris@188:                     m_val[p-1] = m_val[p];
Chris@188:                     m_len[p-1] = m_len[p];
cannam@0:                     p--;
Chris@188:                     if (m_val[p-1] == 3) {
Chris@188:                         m_len[p-1] += m_len[p];
cannam@0:                         p--;
cannam@0:                     }
cannam@0:                 }
Chris@188:                 m_len[p]++;
cannam@0:             }
cannam@0:         }
cannam@0:     }
cannam@0:     int i = 1;
cannam@0:     for (int pp = 1; pp <= p; pp++) {
Chris@188:         int dx = m_val[pp] & 1;
Chris@188:         int dy = m_val[pp] >> 1;
Chris@188:         for (int j = m_len[pp]; j > 0; j--, i++) {
cannam@0:             x[i] = x[i-1] + dx;
cannam@0:             y[i] = y[i-1] + dy;
cannam@0:         }
cannam@0:     }
cannam@0:     return i;
cannam@0: }