[FFmpeg-devel] [PATCH] libavformat/dashdec: Support negative value of the @r attrbute of S in SegmentTimeline element

sanil raut.sanil at gmail.com
Tue Aug 7 05:18:27 EEST 2018


Hi,
The following patch supports parsing negative value of the @r attribute of S in SegmentTimeline element.

Example streams:
1. http://dash.edgesuite.net/dash264/TestCases/1c/qualcomm/1/MultiRate.mpd
2. http://dash.edgesuite.net/dash264/TestCases/1c/qualcomm/2/MultiRate.mpd

---
 libavformat/dashdec.c | 18 +++++++++++++++---
 1 file changed, 15 insertions(+), 3 deletions(-)

diff --git a/libavformat/dashdec.c b/libavformat/dashdec.c
index 89f3ac2..ea960bc 100644
--- a/libavformat/dashdec.c
+++ b/libavformat/dashdec.c
@@ -262,6 +262,12 @@ static int64_t get_segment_start_time_based_on_timeline(struct representation *p
                 goto finish;
 
             start_time += pls->timelines[i]->duration;
+    
+            if (pls->timelines[i]->repeat == -1) {
+                start_time = pls->timelines[i]->duration * cur_seq_no;
+                goto finish;
+            }
+
             for (j = 0; j < pls->timelines[i]->repeat; j++) {
                 num++;
                 if (num == cur_seq_no)
@@ -1341,9 +1347,15 @@ static int64_t calc_max_seg_no(struct representation *pls, DASHContext *c)
     } else if (pls->n_timelines) {
         int i = 0;
         num = pls->first_seq_no + pls->n_timelines - 1;
-        for (i = 0; i < pls->n_timelines; i++) {
-            num += pls->timelines[i]->repeat;
+         for (i = 0; i < pls->n_timelines; i++) {
+            if (pls->timelines[i]->repeat == -1) {
+                int length_of_each_segment = pls->timelines[i]->duration/pls->fragment_timescale;
+                num =  c->period_duration/length_of_each_segment;
+            } else {
+                num += pls->timelines[i]->repeat;
+            }
         }
+
     } else if (c->is_live && pls->fragment_duration) {
         num = pls->first_seq_no + (((get_current_time_in_sec() - c->availability_start_time)) * pls->fragment_timescale)  / pls->fragment_duration;
     } else if (pls->fragment_duration) {
@@ -1952,7 +1964,7 @@ static int dash_read_header(AVFormatContext *s)
         ++stream_index;
     }
 
-  c->is_init_section_common_audio = is_common_init_section_exist(c->audios, c->n_audios);
+    c->is_init_section_common_audio = is_common_init_section_exist(c->audios, c->n_audios);
 
     for (i = 0; i < c->n_audios; i++) {
         struct representation *cur_audio = c->audios[i];
-- 
Thanks,

2.7.4



More information about the ffmpeg-devel mailing list