[FFmpeg-devel] [PATCH] avformat/dashenc: Fix the EXT-X-TARGETDURATION as per the hls specification

Karthick J kjeyapal at akamai.com
Thu Dec 21 12:09:51 EET 2017

From: Karthick Jeyapal <kjeyapal at akamai.com>

The HLS specification states the following about EXT-X-TARGETDURATION  EXT-X-TARGETDURATION

   The EXT-X-TARGETDURATION tag specifies the maximum Media Segment
   duration.  The EXTINF duration of each Media Segment in the Playlist
   file, when rounded to the nearest integer, MUST be less than or equal
   to the target duration; longer segments can trigger playback stalls
   or other errors.  It applies to the entire Playlist file.  Its format


   where s is a decimal-integer indicating the target duration in
   seconds.  The EXT-X-TARGETDURATION tag is REQUIRED.

Currently the dashenc rounds the duration to the next integer,
rather than rounding the duration to the nearest integer.
 libavformat/dashenc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libavformat/dashenc.c b/libavformat/dashenc.c
index 5687530..5368a23 100644
--- a/libavformat/dashenc.c
+++ b/libavformat/dashenc.c
@@ -358,7 +358,7 @@ static void output_segment_list(OutputStream *os, AVIOContext *out, DASHContext
             Segment *seg = os->segments[i];
             double duration = (double) seg->duration / timescale;
             if (target_duration <= duration)
-                target_duration = hls_get_int_from_double(duration);
+                target_duration = lrint(duration);
         ff_hls_write_playlist_header(out_hls, 6, -1, target_duration,

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