1 files changed, 65 insertions, 0 deletions
diff --git a/src/vidutil.c b/src/vidutil.c
new file mode 100644
index 0000000..a6d0b61
--- /dev/null
+++ b/src/vidutil.c
@@ -0,0 +1,65 @@
+/**
+ * @file vidutil.c  Video utility functions
+ *
+ * Copyright (C) 2017 Creytiv.com
+ */
+
+#include <re.h>
+#include <rem.h>
+#include <baresip.h>
+#include "core.h"
+
+
+/**
+ * Calculate the RTP timestamp from Presentation Time Stamp (PTS)
+ * or Decoding Time Stamp (DTS) and framerate.
+ *
+ * @note The calculated RTP Timestamp may NOT wrap around.
+ *
+ * @param pts Presentation Time Stamp (PTS)
+ * @param fps Framerate in [frames per second]
+ *
+ * @return Extended RTP Timestamp
+ */
+uint64_t video_calc_rtp_timestamp(int64_t pts, double fps)
+{
+	uint64_t rtp_ts;
+
+	if (!fps)
+		return 0;
+
+	rtp_ts = ((uint64_t)VIDEO_SRATE * pts) / fps;
+
+	return rtp_ts;
+}
+
+
+/**
+ * Calculate the timestamp in seconds from the RTP timestamp.
+ *
+ * @param rtp_ts RTP Timestamp
+ *
+ * @return Timestamp in seconds
+ */
+double video_calc_seconds(uint64_t rtp_ts)
+{
+	double timestamp;
+
+	/* convert from RTP clockrate to seconds */
+	timestamp = (double)rtp_ts / (double)VIDEO_SRATE;
+
+	return timestamp;
+}
+
+
+/**
+ * Convert a video timestamp to seconds
+ *
+ * @param timestamp Timestamp in VIDEO_TIMEBASE units
+ *
+ * @return Timestamp in seconds
+ */
+double video_timestamp_to_seconds(uint64_t timestamp)
+{
+	return (double)timestamp / (double)VIDEO_TIMEBASE;
+}