1 // Copyright 2004 "Gilles Degottex"
2 
3 // This file is part of "Music"
4 
5 // "Music" is free software; you can redistribute it and/or modify
6 // it under the terms of the GNU Lesser General Public License as published by
7 // the Free Software Foundation; either version 2.1 of the License, or
8 // (at your option) any later version.
9 //
10 // "Music" is distributed in the hope that it will be useful,
11 // but WITHOUT ANY WARRANTY; without even the implied warranty of
12 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 // GNU Lesser General Public License for more details.
14 //
15 // You should have received a copy of the GNU Lesser General Public License
16 // along with this program; if not, write to the Free Software
17 // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
18 
19 
20 #ifndef _CumulativeDiff_h_
21 #define _CumulativeDiff_h_
22 
23 #include <deque>
24 using namespace std;
25 
26 namespace Music
27 {
28 	//! do a Cumulative Diff with a specific wave-length of a desired note
29 	struct CumulativeDiff
30 	{
31 		//! the analysed semi-tone from A3
32 		const int m_ht;
33 		//! his corresponding frequency
34 		const double m_freq;
35 		//! the wave-length
36 		const size_t m_s;
37 		//! latency_factor
38 		double m_latency_factor;
39 
40 		//! unique ctor
41 		/*!
42 		 * \param AFreq frequency of A3 (440.0)
43 		 * \param sampling_rate wave capture sampling rate (11khz;44khz)
44 		 * \param latency_factor latency factor [1;oo[
45 		 * \param ht analysed semi-tone (-48;+48)
46 		 */
47 		CumulativeDiff(double latency_factor, int ht);
48 
49 		//! compute the error
50 		void receive(const deque<double>& buff, size_t start=0);
51 
52 		//! computed error for the desired semi-tone (m_ht)
53 		double m_error;
54 		//!
55 		double m_best_s;
56 	};
57 
58 	//! do a correlation with a specific range of wave-length around a desired note
59 	struct RangedCumulativeDiff
60 	{
61 		//! the analysed semi-tone from A3
62 		const int m_ht;
63 		//! his corresponding frequency
64 		const double m_freq;
65 		//! pitch tolerance for m_freq;
66 		const double m_pitch_tolerance;
67 		//! minimal to maximal scaned wave-length
68 		const size_t m_smin, m_smax;
69 		//! latency_factor
70 		const double m_latency_factor;
71 
72 		//! unique ctor
73 		/*!
74 		 * \param AFreq frequency of A3 (440.0)
75 		 * \param sampling_rate wave capture sampling rate (11khz;44khz)
76 		 * \param latency_factor latency factor [1;oo[
77 		 * \param pitch_tolerance ]0;0.5]
78 		 * \param ht analysed semi-tone (-48;+48)
79 		 */
80 		RangedCumulativeDiff(double pitch_tolerance, double latency_factor, int ht);
81 
82 		//! compute the error
83 		void receive(const deque<double>& buff, size_t start=0);
84 
85 		//! computed error for the desired semi-tone (m_ht)
86 		double m_error;
87 
88 		//! computed minimal error
89 		double m_min_error;
90 
91 		//! the wave length returning the minimal error;
92 		int m_min_wave_length;
93 
94 		static void GetMinWaveLength(double pitch_tolerance, int ht, double& error, double min_wave_length);
95 	};
96 }
97 
98 #endif // _CumulativeDiff_h_
99