#EXT-X-PROGRAM-DATE-TIME may be wrong

Wowza Video (Formerly Streaming Cloud)
1

After starting my transcoder and push rtmp audio stream, my fastly target’s playback url returns like

[I] ➜ http https://cdn3.wowza.com/1/xxxxx/yyyyy/hls/live/playlist.m3u8
HTTP/1.1 200 OK
...
Content-Length: 110
Content-Type: application/x-mpegURL
Date: Fri, 17 Jul 2020 08:28:34 GMT
Via: 1.1 varnish
X-Cache: MISS
X-Cache-Hits: 0
X-Served-By: cache-tyo19920-TYO
X-Timer: S1594974515.832076,VS0,VE78

#EXTM3U
#EXT-X-VERSION:3
#EXT-X-STREAM-INF:BANDWIDTH=67021,CODECS="mp4a.40.2"
../jfpdkl28/1/chunklist_ao.m3u8

It’s fine. But looking into chunklist_ao.m3u8…

[I] ➜ http https://cdn3.wowza.com/1/xxxxx/yyyyy/hls/jfpdkl28/1/chunklist_ao.m3u8
HTTP/1.1 200 OK
...
Content-Length: 559
Content-Type: application/x-mpegURL
Date: Fri, 17 Jul 2020 08:28:37 GMT
Via: 1.1 varnish
X-Cache: MISS
X-Cache-Hits: 0
X-Served-By: cache-tyo19933-TYO
X-Timer: S1594974517.336859,VS0,VE279

#EXTM3U
#EXT-X-VERSION:3
#EXT-X-DISCONTINUITY-SEQUENCE:0
#EXT-X-TARGETDURATION:11
#EXT-X-MEDIA-SEQUENCE:7
#EXT-X-PROGRAM-DATE-TIME:2020-07-17T08:27:54.671Z
#EXTINF:10.031,
0001ah19/media_ao_7.aac
#EXTINF:10.031,
0001ah19/media_ao_8.aac
...
#EXTINF:9.961,
0001ah19/media_ao_15.aac
#EXTINF:10.031,
0001ah19/media_ao_16.aac

#EXT-X-PROGRAM-DATE-TIME may be a little old. And next updates,

[I] ➜ http https://cdn3.wowza.com/1/xxxxx/yyyyy/hls/jfpdkl28/1/chunklist_ao.m3u8
HTTP/1.1 200 OK
...
Content-Length: 560
Content-Type: application/x-mpegURL
Date: Fri, 17 Jul 2020 08:28:53 GMT
Via: 1.1 varnish
X-Cache: HIT
X-Cache-Hits: 1
X-Served-By: cache-tyo19933-TYO
X-Timer: S1594974533.035981,VS0,VE1

#EXTM3U
#EXT-X-VERSION:3
#EXT-X-DISCONTINUITY-SEQUENCE:0
#EXT-X-TARGETDURATION:11
#EXT-X-MEDIA-SEQUENCE:8
#EXT-X-PROGRAM-DATE-TIME:2020-07-17T08:28:14.733Z
#EXTINF:10.031,
0001ah19/media_ao_8.aac
#EXTINF:9.961,
0001ah19/media_ao_9.aac
...
#EXTINF:10.031,
0001ah19/media_ao_16.aac
#EXTINF:10.031,
0001ah19/media_ao_17.aac

One sequence proceeds, and #EXT-X-PROGRAM-DATE-TIME increases 20secs although #EXT-X-TARGETDURATION is 11.

some minutes later…

[I] ➜ http https://cdn3.wowza.com/1/xxxxx/yyyyy/hls/jfpdkl28/1/chunklist_ao.m3u8
HTTP/1.1 200 OK
...
Content-Length: 562
Content-Type: application/x-mpegURL
Date: Fri, 17 Jul 2020 08:34:30 GMT
Via: 1.1 varnish
X-Cache: MISS
X-Cache-Hits: 0
X-Served-By: cache-tyo19940-TYO
X-Timer: S1594974871.676711,VS0,VE156

#EXTM3U
#EXT-X-VERSION:3
#EXT-X-DISCONTINUITY-SEQUENCE:0
#EXT-X-TARGETDURATION:11
#EXT-X-MEDIA-SEQUENCE:42
#EXT-X-PROGRAM-DATE-TIME:2020-07-17T08:39:34.753Z
#EXTINF:9.961,
0001ah19/media_ao_42.aac
#EXTINF:10.031,
0001ah19/media_ao_43.aac
...
#EXTINF:10.031,
0001ah19/media_ao_50.aac
#EXTINF:9.962,
0001ah19/media_ao_51.aac

Now, #EXT-X-PROGRAM-DATE-TIME is absolutely in future. I doubt something wrong with my transcoder or output settings… How this behavior occurs?

Also, I can’t determine if this is the reason, but Android Exoplayer can’t play well our transcoder’s output (It stops playing after some time)

2

I’ll need to check on how compatible Exoplayer’s libraries are with cloud transcoder and fastly.

3

This is definitely not something we would be able to do as far as timestamps for the future segments. I’d submit a support ticket so we can see what is going on here. We may need to test with the Android Exoplayer and the timestamps.