How to incorporate discontinuity time between fragments into the duration of the video player?

[zengspr]

We have an HLS manifest with occasional #EXT-X-DISCONTINUITY tags between fragments, for example:

#EXTM3U
#EXT-X-TARGETDURATION:10
#EXT-X-PLAYLIST-TYPE:EVENT
#EXTINF:10,
<fragment 1 url>
#EXT-X-DISCONTINUITY
#EXTINF:10
<fragment 2 url>
...

Currently the duration of the video player shows up as the sum of the fragment durations, which corresponds to the length of playable video.

While this is correct, is it possible for the video duration to take into account the duration of discontinuities between fragments? For example, if the fragments were like:

[fragment 1]
start_time: 0
duration: 10

#EXT-X-DISCONTINUITY
(10 sec)

[fragment 2]
start_time: 20
duration: 10

Would it be possible to show the video duration as a total of 30s rather than 20s? And either show the last frame of fragment 1 or the first frame of fragment 2 for the 10s intervening time. The goal would be to make the video duration correspond more to "real time" rather than just the playback duration.

We aren't sure whether this is a change to make on the player-side or on the manifest / fragments side.

Thank you!

[robwalch]

Discontinuities do not have a duration.

Add a segment with the duration of the gap preceded by an EXT-X-GAP tag to denote a period with no available media:

https://datatracker.ietf.org/doc/html/draft-pantos-hls-rfc8216bis#section-4.4.4.7