comparison base/RealTime.cpp @ 0:da6937383da8

initial import

+/* -*- c-basic-offset: 4 -*-  vi:set ts=8 sts=4 sw=4: */
+
+/*
+    A waveform viewer and audio annotation editor.
+    Chris Cannam, Queen Mary University of London, 2005
+    
+    This is experimental software.  Not for distribution.
+*/
+
+/*
+   This is a modified version of a source file from the 
+   Rosegarden MIDI and audio sequencer and notation editor.
+   This file copyright 2000-2005 Chris Cannam.
+*/
+
+#include <iostream>
+
+#if (__GNUC__ < 3)
+#include <strstream>
+#define stringstream strstream
+#else
+#include <sstream>
+#endif
+
+using std::cerr;
+using std::endl;
+
+#include "base/RealTime.h"
+
+// A RealTime consists of two ints that must be at least 32 bits each.
+// A signed 32-bit int can store values exceeding +/- 2 billion.  This
+// means we can safely use our lower int for nanoseconds, as there are
+// 1 billion nanoseconds in a second and we need to handle double that
+// because of the implementations of addition etc that we use.
+//
+// The maximum valid RealTime on a 32-bit system is somewhere around
+// 68 years: 999999999 nanoseconds longer than the classic Unix epoch.
+
+#define ONE_BILLION 1000000000
+
+RealTime::RealTime(int s, int n) :
+    sec(s), nsec(n)
+{
+    if (sec == 0) {
+	while (nsec <= -ONE_BILLION) { nsec += ONE_BILLION; --sec; }
+	while (nsec >=  ONE_BILLION) { nsec -= ONE_BILLION; ++sec; }
+    } else if (sec < 0) {
+	while (nsec <= -ONE_BILLION) { nsec += ONE_BILLION; --sec; }
+	while (nsec > 0)             { nsec -= ONE_BILLION; ++sec; }
+    } else { 
+	while (nsec >=  ONE_BILLION) { nsec -= ONE_BILLION; ++sec; }
+	while (nsec < 0)             { nsec += ONE_BILLION; --sec; }
+    }
+}
+
+
+std::ostream &operator<<(std::ostream &out, const RealTime &rt)
+{
+    if (rt < RealTime::zeroTime) {
+	out << "-";
+    } else {
+	out << " ";
+    }
+
+    int s = (rt.sec < 0 ? -rt.sec : rt.sec);
+    int n = (rt.nsec < 0 ? -rt.nsec : rt.nsec);
+
+    out << s << ".";
+
+    int nn(n);
+    if (nn == 0) out << "00000000";
+    else while (nn < (ONE_BILLION / 10)) {
+	out << "0";
+	nn *= 10;
+    }
+    
+    out << n << "R";
+    return out;
+}
+
+std::string
+RealTime::toString() const
+{
+    std::stringstream out;
+    out << *this;
+    
+#if (__GNUC__ < 3)
+    out << std::ends;
+#endif
+
+    std::string s = out.str();
+
+    // remove trailing R
+    return s.substr(0, s.length() - 1);
+}
+
+std::string
+RealTime::toText(bool fixedDp) const
+{
+    if (*this < RealTime::zeroTime) return "-" + (-*this).toText();
+
+    std::stringstream out;
+
+    if (sec >= 3600) {
+	out << (sec / 3600) << ":";
+    }
+
+    if (sec >= 60) {
+	out << (sec % 3600) / 60 << ":";
+    }
+
+    if (sec >= 10) {
+	out << ((sec % 60) / 10);
+    }
+
+    out << (sec % 10);
+    
+    int ms = msec();
+
+    if (ms != 0) {
+	out << ".";
+	out << (ms / 100);
+	ms = ms % 100;
+	if (ms != 0) {
+	    out << (ms / 10);
+	    ms = ms % 10;
+	} else if (fixedDp) {
+	    out << "0";
+	}
+	if (ms != 0) {
+	    out << ms;
+	} else if (fixedDp) {
+	    out << "0";
+	}
+    } else if (fixedDp) {
+	out << ".000";
+    }
+	
+#if (__GNUC__ < 3)
+    out << std::ends;
+#endif
+
+    std::string s = out.str();
+
+    return s;
+}
+
+
+RealTime
+RealTime::operator/(int d) const
+{
+    int secdiv = sec / d;
+    int secrem = sec % d;
+
+    double nsecdiv = (double(nsec) + ONE_BILLION * double(secrem)) / d;
+    
+    return RealTime(secdiv, int(nsecdiv + 0.5));
+}
+
+double 
+RealTime::operator/(const RealTime &r) const
+{
+    double lTotal = double(sec) * ONE_BILLION + double(nsec);
+    double rTotal = double(r.sec) * ONE_BILLION + double(r.nsec);
+    
+    if (rTotal == 0) return 0.0;
+    else return lTotal/rTotal;
+}
+
+long
+RealTime::realTime2Frame(const RealTime &time, unsigned int sampleRate)
+{
+    if (time < zeroTime) return -realTime2Frame(-time, sampleRate);
+
+    // We like integers.  The last term is always zero unless the
+    // sample rate is greater than 1MHz, but hell, you never know...
+
+    long frame =
+	time.sec * sampleRate +
+	(time.msec() * sampleRate) / 1000 +
+	((time.usec() - 1000 * time.msec()) * sampleRate) / 1000000 +
+	((time.nsec - 1000 * time.usec()) * sampleRate) / 1000000000;
+
+    return frame;
+}
+
+RealTime
+RealTime::frame2RealTime(long frame, unsigned int sampleRate)
+{
+    if (frame < 0) return -frame2RealTime(-frame, sampleRate);
+
+    RealTime rt;
+    rt.sec = frame / long(sampleRate);
+    frame -= rt.sec * long(sampleRate);
+    rt.nsec = (int)(((float(frame) * 1000000) / long(sampleRate)) * 1000);
+    return rt;
+}
+
+const RealTime RealTime::zeroTime(0,0);
+