Simplify time representation; better in-tree DCP subtitle parser.

1 files changed, 154 insertions, 0 deletions

diff --git a/src/sub_time.cc b/src/sub_time.cc
new file mode 100644
index 0000000..e304310
--- /dev/null
+++ b/src/sub_time.cc
@@ -0,0 +1,154 @@
+/*
+    Copyright (C) 2014-2015 Carl Hetherington <cth@carlh.net>
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+*/
+
+#include "sub_time.h"
+#include "exceptions.h"
+#include <cmath>
+#include <iomanip>
+
+using std::ostream;
+using std::cout;
+using std::setw;
+using std::setfill;
+using boost::optional;
+using namespace sub;
+
+bool
+sub::operator< (sub::Time const & a, sub::Time const & b)
+{
+	if (a._seconds != b._seconds) {
+		return a._seconds < b._seconds;
+	}
+
+	if (!a._rate && !b._rate) {
+		/* Can compare if neither has a specified frame rate */
+		return a._frames < b._frames;
+	}
+
+	if ((a._rate && !b._rate) || (!a._rate && b._rate)) {
+		throw UnknownFrameRateError ();
+	}
+	
+	return (a._frames * a._rate.get().numerator * b._rate.get().denominator) < (b._frames * b._rate.get().numerator * a._rate.get().denominator);
+}
+
+bool
+sub::operator> (sub::Time const & a, sub::Time const & b)
+{
+	if (a._seconds != b._seconds) {
+		return a._seconds > b._seconds;
+	}
+
+	if (!a._rate && !b._rate) {
+		/* Can compare if neither has a specified frame rate */
+		return a._frames > b._frames;
+	}
+
+	if ((a._rate && !b._rate) || (!a._rate && b._rate)) {
+		throw UnknownFrameRateError ();
+	}
+	
+	return (a._frames * a._rate.get().numerator * b._rate.get().denominator) > (b._frames * b._rate.get().numerator * a._rate.get().denominator);
+}
+
+bool
+sub::operator== (sub::Time const & a, sub::Time const & b)
+{
+	if (!a._rate && !b._rate) {
+		/* Can compare if neither has a specified frame rate */
+		return (a._seconds == b._seconds && a._frames == b._frames);
+	}
+
+	if ((a._rate && !b._rate) || (!a._rate && b._rate)) {
+		throw UnknownFrameRateError ();
+	}
+
+	if (a._seconds != b._seconds) {
+		return false;
+	}
+
+	return (a._frames * a._rate.get().numerator * b._rate.get().denominator) == (b._frames * b._rate.get().numerator * a._rate.get().denominator);
+}
+
+bool
+sub::operator!= (sub::Time const & a, sub::Time const & b)
+{
+	return !(a == b);
+}
+
+ostream&
+sub::operator<< (ostream& s, Time const & t)
+{
+	s << setw (2) << setfill('0') << t.hours() << ":"
+	  << setw (2) << setfill('0') << t.minutes() << ":"
+	  << setw (2) << setfill('0') << t.seconds() << ":"
+	  << t._frames;
+
+	if (t._rate) {
+		s << " @ " << t._rate.get().numerator << "/" << t._rate.get().denominator;
+	}
+
+	return s;
+}
+
+int
+Time::hours () const
+{
+	return _seconds / 3600;
+}
+
+int
+Time::minutes () const
+{
+	return (_seconds - hours() * 3600) / 60;
+}
+
+int
+Time::seconds () const
+{
+	return (_seconds - hours() * 3600 - minutes() * 60);
+}
+
+int
+Time::frames_at (Rational rate) const
+{
+	if (!_rate) {
+		throw UnknownFrameRateError ();
+	}
+	
+	return rint (double (_frames) * _rate.get().denominator * rate.numerator / (_rate.get().numerator * rate.denominator));
+}
+
+int
+Time::milliseconds () const
+{
+	return frames_at (Rational (1000, 1));
+}
+
+Time
+Time::from_hmsf (int h, int m, int s, int f, optional<Rational> rate)
+{
+	return Time (h * 3600 + m * 60 + s, f, rate);
+}
+
+Time
+Time::from_hms (int h, int m, int s, int ms)
+{
+	return Time (h * 3600 + m * 60 + s, ms, Rational (1000, 1));
+}