Low-Latency MPEG-DASH streaming (Chunked CMAF)

[jplogos]

Describe the bug I am trying to do CMAL ULL (chunked encoding) with ovenmediaengine (OvenMediaEngine-0.12.1)

1. Sent RTMP input to the OME.
2. Streaming the below LL-DASH URL with DASH Player

URL: http://myip:80/app/vxstream/manifest_ll.mpd

3. I dont see any chunked encoding output as i see form pcap trace. I see "contnet-length" in the HTTP response from OME.
4. As per CTE (chunked Transfer Encoding) we should not see content-lenght and segments should be chunked and delivered.

To Reproduce

Expected behavior Expecting chunked tranfer in the pcap.

Logs Please upload the entire OvenMediaEngine.log. You may delete important personal information.

[2021-08-06 03:13:18.567] W [AppWorker:3006553] LLDASH | cmaf_stream_server.cpp:149 | Failed to send the chunked data for [#default#app/vxstream, 72_video_ll.m4s] to <ClientSocket: 0x7f316809d3a0, #116, Connected, TCP, Nonblocking, 10.93.9.147:64402> (17788 bytes) [2021-08-06 03:13:18.567] W [AppWorker:3006553] LLDASH | cmaf_stream_server.cpp:149 | Failed to send the chunked data for [#default#app/vxstream, 72_video_ll.m4s] to <ClientSocket: 0x7f3168062d50, #117, Connected, TCP, Nonblocking, 10.93.9.147:64403> (17788 bytes) [2021-08-06 03:13:18.567] W [AppWorker:3006553] LLDASH | cmaf_stream_server.cpp:149 | Failed to send the chunked data for [#default#app/vxstream, 72_video_ll.m4s] to <ClientSocket: 0x7f316806d9a0, #118, Connected, TCP, Nonblocking, 10.93.9.147:64404> (17788 bytes) [2021-08-06 03:13:18.567] W [AppWorker:3006553] LLDASH | cmaf_stream_server.cpp:149 | Failed to send the chunked data for [#default#app/vxstream, 72_video_ll.m4s] to <ClientSocket: 0x7f316809aa40, #119, Connected, TCP, Nonblocking, 10.93.9.147:64405> (17788 bytes) [2021-08-06 03:13:18.567] W [AppWorker:3006553] LLDASH | cmaf_stream_server.cpp:149 | Failed to send the chunked data for [#default#app/vxstream, 72_video_ll.m4s] to <ClientSocket: 0x7f31680b9080, #120, Connected, TCP, Nonblocking, 10.93.9.147:64406> (17788 bytes) [2021-08-06 03:13:18.567] W [AppWorker:3006553] LLDASH | cmaf_stream_server.cpp:149 | Failed to send the chunked data for [#default#app/vxstream, 72_video_ll.m4s] to <ClientSocket: 0x7f3168077ad0, #121, Connected, TCP, Nonblocking, 10.93.9.147:64407> (17788 bytes) [2021-08-06 03:13:18.567] W [AppWorker:3006553] LLDASH | cmaf_stream_server.cpp:149 | Failed to send the chunked data for [#default#app/vxstream, 72_video_ll.m4s] to <ClientSocket: 0x7f316809a750, #122, Connected, TCP, Nonblocking, 10.93.9.147:64408> (17788 bytes) [2021-08-06 03:13:18.567] W [AppWorker:3006553] LLDASH | cmaf_stream_server.cpp:149 | Failed to send the chunked data for [#default#app/vxstream, 72_video_ll.m4s] to <ClientSocket: 0x7f3168075a00, #123, Connected, TCP, Nonblocking, 10.93.9.147:64409> (17788 bytes)

Server (please complete the following information):

• OS: Ubuntu
• OvenMediaEngine Version: 0.12.1
• Branch: (https://github.com/AirenSoft/OvenMediaEngine.git)

Player (please complete the following information): https://reference.dashif.org/dash.js/nightly/samples/dash-if-reference-player/index.html

Additional context Add any other context about the problem here.

Thank you.

[getroot]

Did you turn on the Low Latency Mode option in the DASH Reference Player?

Alternatively you can test with Enable Low Latency MPEG DASH on http://demo.ovenplayer.com/.

[danrossi]

I'm trying to play LL Dash test via a Docker image. I've only managed to get HLS working so far. RTMP -> webrtc not working either. I'm RTMP publishing to local docker then trying to play back LL Dash and I get the following errors. The stream partly plays but mostly 404 errors on fragments.

http://localhost:8080/app/stream/manifest_ll.mpd

[2021-08-06 13:37:47.417] W [SegWorker:59] HTTPPublisher | segment_publisher.cpp:169 | Could not find a segment for LLDASH Publisher [#default#app/stream, 29_video_ll.m4s]

[2021-08-06 13:37:47.539] W [SegWorker:56] HTTPPublisher | segment_publisher.cpp:169 | Could not find a segment for LLDASH Publisher [#default#app/stream, 29_video_ll.m4s]

[basisbit]

I'd suggest not spending any time of LL-DASH right now. It is not usable with OME unless you are very close to the server, use a certain ll-dash player library version and use chrome. See https://github.com/AirenSoft/OvenMediaEngine/issues/268 and https://github.com/AirenSoft/OvenMediaEngine/issues/279 .

If you want low latency playback, I'd suggest using WebRTC over UDP based playback using OvenPlayer with Fallback to WebRTC over TCP, and if that also fails, fallback to HLS.

[mpisat]

LL-DASH works if latency is low. My tests work fine with 40ms latency with 2 seconds. It also works with 1 second latency but is not perfect. When I test it with > 200 ms latency, then even 2 seconds latency doesn't help.

[basisbit]

LL-DASH works if latency is low.

only in chrome. see above mentioned issues.

[jplogos]

Did you turn on the Low Latency Mode option in the DASH Reference Player?

Alternatively you can test with Enable Low Latency MPEG DASH on http://demo.ovenplayer.com/.

Hi @getroot I have used http://demo.ovenplayer.com/ player and able to see chunked transfer from OME.

Thank you.

[danrossi]

I just wanted to test this feature. And it was failing subscribing from a local Docker image. Same machine. RTMP publish is ok as HLS works. I am having major subscribe problems with this server either custom built or Docker. No idea why. WebRTC publish fails. WebRTC subscribe from RTMP fails.

[getroot]

We're sorry, but with the release of LLHLS, we have decided to no longer update LLDASH. Because LLHLS has better performance and compatibility, we decided it was a better decision for everyone to focus more of our energy on it.

Instead, we will continue to focus more on LLHLS and WebRTC. Thanks for your contribution.

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.