Back-port v2's rename and slight extension of FrameRateConversion.

1 files changed, 58 insertions, 0 deletions

diff --git a/src/lib/frame_rate_change.h b/src/lib/frame_rate_change.h
new file mode 100644
index 000000000..6165f6840
--- /dev/null
+++ b/src/lib/frame_rate_change.h
@@ -0,0 +1,58 @@
+/*
+    Copyright (C) 2012-2014 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 <string>
+
+struct FrameRateChange
+{
+	FrameRateChange (float, int);
+
+	/** @return factor by which to multiply a source frame rate
+	    to get the effective rate after any skip or repeat has happened.
+	*/
+	float factor () const {
+		if (skip) {
+			return 0.5;
+		}
+
+		return repeat;
+	}
+
+	/** true to skip every other frame */
+	bool skip;
+	/** number of times to use each frame (e.g. 1 is normal, 2 means repeat each frame once, and so on) */
+	int repeat;
+	/** true if this DCP will run its video faster or slower than the source
+	 *  without taking into account `repeat' nor `skip'.
+	 *  (e.g. change_speed will be true if
+	 *	    source is 29.97fps, DCP is 30fps
+	 *	    source is 14.50fps, DCP is 30fps
+	 *  but not if
+	 *	    source is 15.00fps, DCP is 30fps
+	 *	    source is 12.50fps, DCP is 25fps)
+	 */
+	bool change_speed;
+
+	/** Amount by which the video is being sped-up in the DCP; e.g. for a
+	 *  24fps source in a 25fps DCP this would be 25/24.
+	 */
+	float speed_up;
+
+	std::string description;
+};