[FFmpeg-devel] [PATCH] [UPDATE] HLS, add option to skip down streams,

[wm4]

On Fri, 21 Apr 2017 11:34:39 +0100
Amine kabab <kabab1993 at gmail.com> wrote:

> Hi Ben, thanks for reviewing the patch,
> 
> 
> On 21/04/2017 08:13, Benoit Fouet wrote:
> > Hi,
> >
> >
> > On 20/04/2017 18:18, Amine kabab wrote:  
> >> From 5079f9b7114589626a4c9fff0fbb8f6e0d2f4fd9 Mon Sep 17 00:00:00 2001
> >> From: amine kabab <kabab1993 at gmail.com>
> >> Date: Thu, 20 Apr 2017 15:59:42 +0000
> >> Subject: [PATCH] HLS skip down streams
> >>
> >> ---
> >>  libavformat/hls.c | 14 +++++++++++++-
> >>  1 file changed, 13 insertions(+), 1 deletion(-)
> >>
> >> diff --git a/libavformat/hls.c b/libavformat/hls.c
> >> index bac53a4..26d7679 100644
> >> --- a/libavformat/hls.c
> >> +++ b/libavformat/hls.c
> >> @@ -194,6 +194,7 @@ typedef struct HLSContext {
> >>  
> >>      int cur_seq_no;
> >>      int live_start_index;
> >> +    int skip_down_streams;
> >>      int first_packet;
> >>      int64_t first_timestamp;
> >>      int64_t cur_timestamp;
> >> @@ -1652,11 +1653,20 @@ static int hls_read_header(AVFormatContext *s)
> >>      /* If the playlist only contained playlists (Master Playlist),
> >>       * parse each individual playlist. */
> >>      if (c->n_playlists > 1 || c->playlists[0]->n_segments == 0) {
> >> +        int all_failed = 1;
> >>          for (i = 0; i < c->n_playlists; i++) {
> >>              struct playlist *pls = c->playlists[i];
> >> -            if ((ret = parse_playlist(c, pls->url, pls, NULL)) < 0)
> >> +            av_log(NULL, AV_LOG_WARNING, "Trying %s\n", pls->url);  
> > Do you really want to keep this trace?  
> I think the log is very helpful in this part, otherwise if the playlist is too long the user will get no feedback.
> >  
> >> +            ret = parse_playlist(c, pls->url, pls, NULL);
> >> +            if (c->skip_down_streams && ret >= 0) {
> >> +                all_failed = 0;
> >> +            } else if (!c->skip_down_streams && ret < 0){
> >>                  goto fail;
> >> +            }  
> > If I understand correctly, that means that if you do not set
> > skip_down_streams and the playlist parsing is OK, you will not unset
> > all_failed, and bail out below. Is this really what you want?  
> I wanted to keep the normal behavior, I've updated the patch to fix the issue
> >  
> >>          }
> >> +
> >> +        if (all_failed)
> >> +            goto fail;
> >>      }
> >>  
> >>      if (c->variants[0]->playlists[0]->n_segments == 0) {
> >> @@ -2126,6 +2136,8 @@ static int hls_probe(AVProbeData *p)
> >>  static const AVOption hls_options[] = {
> >>      {"live_start_index", "segment index to start live streams at (negative values are from the end)",
> >>          OFFSET(live_start_index), AV_OPT_TYPE_INT, {.i64 = -3}, INT_MIN, INT_MAX, FLAGS},
> >> +    {"skip_down_streams", "continue playback of HLS when one of the variant streams are down",
> >> +        OFFSET(skip_down_streams), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, FLAGS},
> >>      {NULL}
> >>  };  
> 

Does this code affect only selected streams, or all of them?