nDVR insert EXT-DISCONTINUITY on append

Wowza Streaming Engine
1

Hello,

I am using WowzaStreamingEngine to produce an HLS LIVE+DVR stream.

The DVR is set up with a 5 minutes window. I can correctly send my video to wowza and see it correctly through DVR.

I set the Archive Method to append so, according to specifications, if I play over an already existing filename, I overwrite it with the new appending new parts.

I use this functionality to maintain a single stream name but appending dynamically content from different sources. (the last it cames it overwrite the previous)

This kinda works, but I noticed that if it elapses certain time between the last write and a new write on the same file, and a viewer is viewing the HLS stream with native safari html5 video tag, the stream freeze at the switch.

I guess this happen because the playlist file is the same, but we have an unexpected hole in the chuncklist. Since I cannot avoid to have this hole I’m wandering if it is possible to set up wowza to inject an EXT-X-DISCONTINUITY tag in the playlist right before each append on the same playlist.

I found the option dvrAppendDiscontinuityDelta that says When using append mode, a short time delta, in milliseconds, is placed between the old recording and the newly appended recording. This property applies to append mode. and I enabled it with a value of 500 (500ms EXT discontinuity I guess), but if I check the playlist with curl after the append, I don’t see any EXT-X-DISCONTINUITY tag in the DVR chunklist.

Am I doing something wrong? Is this option the option I am looking for? Do I have to implement a wowza module to insert these EXT-X-DISCONTINUITY tags between subsequents DVR appends?

Thanks in advance for the help.

Simone

2

Hi,

This was previously addressed in ticket #196925. I am copying the response here for others:

The tag would be added if there was a codec change within the DVR window, so it may not appear before every append.

The “dvrAppendDiscontinuityDelta” is only related to the DVR and its functions on your Wowza Streaming Engine instance, and these two tags are not directly related since one is covering discontinuity of the recordings and slight time offsets, and the other is covering the discontinuity of Codecs with in an HLS Chunklist.

Michelle