"Received discontinuity error" from mediastreamvalidator

Wowza Streaming Engine
1

Hi, I’m testing Wowza 4.3.0 for live streaming service.

To prepare for Apple review, I’ve checked my HLS playback stream by Apple Media Tool(mediastreamvalidator), and got the result as follows.

media-unikviun7_3096.ts:

ERROR: (-12976) Received discontinuity error

–> Track ID: 256

ERROR: (-12976) Received discontinuity error

–> Track ID: 257

So I checked ts by “ffprobe -show_packets” command and found that pts of the second audio packet doesn’t matched with “pts of the first audio packet + duration”.

: 2507776000 (1st pts) + 2089 (1st dur) = 2507778089, but 2nd pts is 2507778090

[PACKET]

codec_type=audio

stream_index=1

pts=2507776000

pts_time=27864.177778

dts=2507776000

dts_time=27864.177778

duration=2089

duration_time=0.023211

convergence_duration=N/A

convergence_duration_time=N/A

size=186

pos=N/A

flags=K

[/PACKET]

[PACKET]

codec_type=audio

stream_index=1

pts=2507778090

pts_time=27864.201000

dts=2507778090

dts_time=27864.201000

duration=2089

duration_time=0.023211

convergence_duration=N/A

convergence_duration_time=N/A

size=191

pos=N/A

flags=K

[/PACKET]

I think that this is the root cause of “discontinuity error”. Any idea about this problem?

My environment details:

  • Broadcasting client: OBS(Open Broadcaster Software) 0.11.1 by default settings (H.264/AAC)

  • Wowza Input protocol: RTMP

  • Wowza Output protocol: HLS

  • Wowza Transcode options

  • Video: H.264/800000 bps/default encoding impl./Baseline profile/30, 60 or 90 key frame interval

  • Frame: letterbox/1280x720/no crop

  • Audio: AAC/64000 bps

  • No overlay image

  • HLS options (cupertino streaming packetizer)

  • cupertinoBitrateAdjustmentFactor: 110

  • cupertinoCalculateCodecs : false

  • cupertinoPacketizeAllStreamsAsTS : true

  • httpOriginMode : on

  • Apple Media Tool
  • mediastreamvalidator: Beta Version 1.1(150923)

Regards,

Hyangtack

2

Hi Hyangtack,

Please add the following property to your live or VOD application in order to remove the discontinuity errors from MediaStreamValidator.

cupertinoOnChunkStartResetCounter

false

Boolean

The above property needs to be added in the HTTPStreamers/Properties container for VOD applications, and in the LiveStreamPacketizer/Properties for live applications. Do make sure that you add it to the correct container, since there are several Properties containers in the configuration file. Save your changes and restart the application to test the stream again.

Michelle

3

Thanks for the update and glad you got this sorted.

Regards,

Salvadore

4

Hi Michelle,

There’s no “discontinuity error” after setting the parameter you mentioned.

Thank you very much.