decoder/ffmpeg: use AVStream::duration

Use the duration of the stream we're actually decoding - not the
"global" attribute AVFormatContext::duration which may differ.

1 files changed, 25 insertions, 0 deletions

diff --git a/src/lib/ffmpeg/Time.hxx b/src/lib/ffmpeg/Time.hxx
index 0e6ba2e84..7f2146016 100644
--- a/src/lib/ffmpeg/Time.hxx
+++ b/src/lib/ffmpeg/Time.hxx
@@ -60,6 +60,31 @@ RatioToAVRational()
 }
 
 /**
+ * Convert a FFmpeg time stamp to a #SongTime.
+ */
+gcc_const
+static inline SongTime
+FromFfmpegTime(int64_t t, const AVRational time_base)
+{
+	assert(t != (int64_t)AV_NOPTS_VALUE);
+
+	return SongTime::FromMS(av_rescale_q(t, time_base,
+					     (AVRational){1, 1000}));
+}
+
+/**
+ * Convert a FFmpeg time stamp to a #SignedSongTime.
+ */
+gcc_const
+static inline SignedSongTime
+FromFfmpegTimeChecked(int64_t t, const AVRational time_base)
+{
+	return t != (int64_t)AV_NOPTS_VALUE
+		? SignedSongTime(FromFfmpegTime(t, time_base))
+		: SignedSongTime::Negative();
+}
+
+/**
  * Convert a #SongTime to a FFmpeg time stamp with the given base.
  */
 gcc_const