Ticket #8825: 0003-avformat-webvttdec-Calculate-hls_ts_offset-relative-.patch

File 0003-avformat-webvttdec-Calculate-hls_ts_offset-relative-.patch, 1.7 KB (added by giwiniswut, 6 years ago)

A change to treat X-TIMESTAMP-MAPs relative to the first fragment.

  • libavformat/webvttdec.c 

    From 1b60d647a7ca6c1c502c821265b689b847f7255a Mon Sep 17 00:00:00 2001
From: Sebastian Zeller <SebiderSushi@t-online.de>
Date: Tue, 5 Jan 2021 07:09:34 +0100
Subject: [PATCH 3/3] avformat/webvttdec: Calculate hls_ts_offset relative to
 first fragment

---
 libavformat/webvttdec.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/libavformat/webvttdec.c b/libavformat/webvttdec.c
index c6acf8e5bb..cf56f0c232 100644
    a b static int webvtt_read_header(AVFormatContext *s)  
    7171    AVStream *st = avformat_new_stream(s, NULL);
    7272    int has_hls_timestamp_map = 0;
    7373    int64_t hls_ts_offset;
     74    int64_t hls_ts_offset_global = -1;
    7475
    7576    if (!st)
    7677        return AVERROR(ENOMEM);
    … … static int webvtt_read_header(AVFormatContext *s)  
    121122                        int64_t mpegts_ts = strtoll(mpegts_str + 7, NULL, 10);
    122123
    123124                        if (native_ts != AV_NOPTS_VALUE) {
    124                             hls_ts_offset = mpegts_ts - native_ts * 90;
     125                            /*
     126                            * In livestreams the timestamp map can start at any mpegts time.
     127                            * Consequently, everything should be treated relative to the first timestamp.
     128                            */
     129                            if (hls_ts_offset_global == -1) {
     130                                hls_ts_offset_global = mpegts_ts;
     131                            }
     132                            hls_ts_offset = mpegts_ts - native_ts * 90 - hls_ts_offset_global;
    125133                            has_hls_timestamp_map = 1;
    126134                            avpriv_set_pts_info(st, 33, 1, 90000);
    127135                        }