2 Copyright (C) 2014-2016 Carl Hetherington <cth@carlh.net>
4 This file is part of DCP-o-matic.
6 DCP-o-matic is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
11 DCP-o-matic is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with DCP-o-matic. If not, see <http://www.gnu.org/licenses/>.
21 /** @file src/lib/dcpomatic_time.h
22 * @brief Types to describe time.
25 #ifndef DCPOMATIC_TIME_H
26 #define DCPOMATIC_TIME_H
28 #include "frame_rate_change.h"
29 #include "dcpomatic_assert.h"
30 #include <boost/optional.hpp>
36 class dcpomatic_round_up_test;
38 /** A time in seconds, expressed as a number scaled up by Time::HZ. We want two different
39 * versions of this class, ContentTime and DCPTime, and we want it to be impossible to
40 * convert implicitly between the two. Hence there's this template hack. I'm not
41 * sure if it's the best way to do it.
43 * S is the name of `this' class and O is its opposite (see the typedefs below).
45 template <class S, class O>
55 explicit Time (Type t)
59 explicit Time (Type n, Type d)
63 /* Explicit conversion from type O */
64 Time (Time<O, S> d, FrameRateChange f);
70 bool operator< (Time<S, O> const & o) const {
74 bool operator<= (Time<S, O> const & o) const {
78 bool operator== (Time<S, O> const & o) const {
82 bool operator!= (Time<S, O> const & o) const {
86 bool operator>= (Time<S, O> const & o) const {
90 bool operator> (Time<S, O> const & o) const {
94 Time<S, O> operator+ (Time<S, O> const & o) const {
95 return Time<S, O> (_t + o._t);
98 Time<S, O> & operator+= (Time<S, O> const & o) {
103 Time<S, O> operator- () const {
104 return Time<S, O> (-_t);
107 Time<S, O> operator- (Time<S, O> const & o) const {
108 return Time<S, O> (_t - o._t);
111 Time<S, O> & operator-= (Time<S, O> const & o) {
116 /** Round up to the nearest sampling interval
117 * at some sampling rate.
118 * @param r Sampling rate.
120 Time<S, O> round_up (float r) const {
121 Type const n = llrintf (HZ / r);
122 Type const a = _t + n - 1;
123 return Time<S, O> (a - (a % n));
126 double seconds () const {
127 return double (_t) / HZ;
130 Time<S, O> abs () const {
131 return Time<S, O> (std::abs (_t));
134 template <typename T>
135 int64_t frames_round (T r) const {
136 /* We must cast to double here otherwise if T is integer
137 the calculation will round down before we get the chance
140 return llrint (_t * double(r) / HZ);
143 template <typename T>
144 int64_t frames_floor (T r) const {
145 return floor (_t * r / HZ);
148 template <typename T>
149 int64_t frames_ceil (T r) const {
150 /* We must cast to double here otherwise if T is integer
151 the calculation will round down before we get the chance
154 return ceil (_t * double(r) / HZ);
157 /** @param r Frames per second */
158 template <typename T>
159 void split (T r, int& h, int& m, int& s, int& f) const
161 /* Do this calculation with frames so that we can round
162 to a frame boundary at the start rather than the end.
164 int64_t ff = frames_round (r);
173 f = static_cast<int> (ff);
176 template <typename T>
177 std::string timecode (T r) const {
182 split (r, h, m, s, f);
185 snprintf (buffer, sizeof (buffer), "%02d:%02d:%02d:%02d", h, m, s, f);
190 static Time<S, O> from_seconds (double s) {
191 return Time<S, O> (llrint (s * HZ));
195 static Time<S, O> from_frames (int64_t f, T r) {
196 DCPOMATIC_ASSERT (r > 0);
197 return Time<S, O> (f * HZ / r);
200 static Time<S, O> delta () {
201 return Time<S, O> (1);
204 static Time<S, O> min () {
205 return Time<S, O> (-INT64_MAX);
208 static Time<S, O> max () {
209 return Time<S, O> (INT64_MAX);
213 friend struct dcptime_round_up_test;
216 static const int HZ = 96000;
219 class ContentTimeDifferentiator {};
220 class DCPTimeDifferentiator {};
222 /* Specializations for the two allowed explicit conversions */
225 Time<ContentTimeDifferentiator, DCPTimeDifferentiator>::Time (Time<DCPTimeDifferentiator, ContentTimeDifferentiator> d, FrameRateChange f);
228 Time<DCPTimeDifferentiator, ContentTimeDifferentiator>::Time (Time<ContentTimeDifferentiator, DCPTimeDifferentiator> d, FrameRateChange f);
230 /** Time relative to the start or position of a piece of content in its native frame rate */
231 typedef Time<ContentTimeDifferentiator, DCPTimeDifferentiator> ContentTime;
232 /** Time relative to the start of the output DCP in its frame rate */
233 typedef Time<DCPTimeDifferentiator, ContentTimeDifferentiator> DCPTime;
241 TimePeriod (T f, T t)
246 /** start time of sampling interval that the period is from */
248 /** start time of next sampling interval after the period */
251 T duration () const {
255 TimePeriod<T> operator+ (T const & o) const {
256 return TimePeriod<T> (from + o, to + o);
259 boost::optional<TimePeriod<T> > overlap (TimePeriod<T> const & other) {
260 T const max_from = std::max (from, other.from);
261 T const min_to = std::min (to, other.to);
263 if (max_from >= min_to) {
264 return boost::optional<TimePeriod<T> > ();
267 return TimePeriod<T> (max_from, min_to);
270 bool contains (T const & other) const {
271 return (from <= other && other < to);
274 bool operator== (TimePeriod<T> const & other) const {
275 return from == other.from && to == other.to;
279 typedef TimePeriod<ContentTime> ContentTimePeriod;
280 typedef TimePeriod<DCPTime> DCPTimePeriod;
282 DCPTime min (DCPTime a, DCPTime b);
283 DCPTime max (DCPTime a, DCPTime b);
284 ContentTime min (ContentTime a, ContentTime b);
285 ContentTime max (ContentTime a, ContentTime b);
286 std::string to_string (ContentTime t);
287 std::string to_string (DCPTime t);
288 std::string to_string (DCPTimePeriod p);