[FFmpeg-devel] [PATCH] avformat/hls allow playback when some variant streams are unavailable

[Tim Hunt]

My last patch was slightly convoluted and really dumb.

I suspect it impacts on a couple of checks for
variants[0]->playlists[0]->finished and the problem will be when a non live
stream has two variants using EXT-X-ENDLIST and the first stream in the
playlist is down? Not sure how to approach this, will look into it more
later.

---
 libavformat/hls.c | 17 +++++++++++------
 1 file changed, 11 insertions(+), 6 deletions(-)

diff --git a/libavformat/hls.c b/libavformat/hls.c
index bac53a4..26b8751 100644
--- a/libavformat/hls.c
+++ b/libavformat/hls.c
@@ -1611,7 +1611,7 @@ static int hls_read_header(AVFormatContext *s)
     void *u = (s->flags & AVFMT_FLAG_CUSTOM_IO) ? NULL : s->pb;
     HLSContext *c = s->priv_data;
     int ret = 0, i;
-    int highest_cur_seq_no = 0;
+    int highest_cur_seq_no = 0, found_segments;

     c->ctx                = s;
     c->interrupt_callback = &s->interrupt_callback;
@@ -1652,14 +1652,20 @@ 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) {
+        found_segments = -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)
-                goto fail;
+            if (parse_playlist(c, pls->url, pls, NULL) == 0 &&
pls->n_segments > 0)
+                found_segments = 1;
         }
-    }

-    if (c->variants[0]->playlists[0]->n_segments == 0) {
+        if(found_segments == -1) {
+            av_log(NULL, AV_LOG_WARNING, "Empty playlist\n");
+            ret = AVERROR_EOF;
+            goto fail;
+        }
+    } else if (c->variants[0]->playlists[0]->n_segments == 0) {
         av_log(NULL, AV_LOG_WARNING, "Empty playlist\n");
         ret = AVERROR_EOF;
         goto fail;
@@ -1805,7 +1811,6 @@ static int hls_read_header(AVFormatContext *s)
     }

     update_noheader_flag(s);
-
     return 0;
 fail:
     hls_close(s);
-- 
2.7.4


On Thu, Apr 13, 2017 at 12:43 AM, Tim Hunt <tnhunt at gmail.com> wrote:

> addresses ticket #2617
>
> The test url given in the bug report is now working and has been playing
> for a couple of hours.
>
> http://amd.cdn.turner.com/adultswim/big/streams/playlists/toonami.m3u8
>
> ---
>  libavformat/hls.c | 26 ++++++++++++++++++++------
>  1 file changed, 20 insertions(+), 6 deletions(-)
>
> diff --git a/libavformat/hls.c b/libavformat/hls.c
> index bac53a4..87e0c71 100644
> --- a/libavformat/hls.c
> +++ b/libavformat/hls.c
> @@ -1610,8 +1610,8 @@ static int hls_read_header(AVFormatContext *s)
>  {
>      void *u = (s->flags & AVFMT_FLAG_CUSTOM_IO) ? NULL : s->pb;
>      HLSContext *c = s->priv_data;
> -    int ret = 0, i;
> -    int highest_cur_seq_no = 0;
> +    int ret = 0, i, j;
> +    int highest_cur_seq_no = 0, found_segments;
>
>      c->ctx                = s;
>      c->interrupt_callback = &s->interrupt_callback;
> @@ -1655,11 +1655,26 @@ static int hls_read_header(AVFormatContext *s)
>          for (i = 0; i < c->n_playlists; i++) {
>              struct playlist *pls = c->playlists[i];
>              if ((ret = parse_playlist(c, pls->url, pls, NULL)) < 0)
> -                goto fail;
> +                continue;
>          }
> -    }
>
> -    if (c->variants[0]->playlists[0]->n_segments == 0) {
> +        found_segments = -1;
> +        for(i = 0; i < c->n_variants && found_segments == -1; i++) {
> +            struct variant *var = c->variants[i];
> +            for(j = 0; j < var->n_playlists; j++) {
> +                if(var->playlists[j]->n_segments > 0) {
> +                    found_segments = 1;
> +                    break;
> +                }
> +            }
> +        }
> +
> +        if(found_segments == -1) {
> +            av_log(NULL, AV_LOG_WARNING, "Empty playlist\n");
> +            ret = AVERROR_EOF;
> +            goto fail;
> +        }
> +    } else if (c->variants[0]->playlists[0]->n_segments == 0) {
>          av_log(NULL, AV_LOG_WARNING, "Empty playlist\n");
>          ret = AVERROR_EOF;
>          goto fail;
> @@ -1805,7 +1820,6 @@ static int hls_read_header(AVFormatContext *s)
>      }
>
>      update_noheader_flag(s);
> -
>      return 0;
>  fail:
>      hls_close(s);
> --
> 2.7.4
>