Capturing VOD from a file

[Luca]

Hi

I am trying to implement a feature that lets me add a stream a VOD file to a mixer, however I wold like to also add the functionality to pause the video stream and start it from the beginning when its tie to push it into the mixer

Is this possible?

Thank you in advance for your response
Best
Luca

 

[Max]

Good day.
You can use REST API: VOD capture management with REST API

• /vod/startup to start capture from VOD
• /mixer/add to add VOD stream to mixer
• /vod/terminate to stop VOD stream

 

[Luca]

Thank you Max

Not 100% what I was asking, but let me clarify

The application I would like to build would work a bit like an MCU, however would also give the possibility to mix OnDemand files as live files.

Flashphoner already supports this feature, but functionality is pretty weak, I would need to be able to "Pause" the video and restart when I need, right now, once you add the live translation of the OD video in the server, the video will start playing behind the scenes and doing the whole process you have suggested whilst live is not particularly smooth as it takes time to load making the process clunky.
Also, when I add a stream live to the mixer there is a lag between the time I push the command and the time the stream loads in which a Grey Box is visible, please could you let me know if there is a way to smooth this out when adding streams to a mixer?

Thank you in advance

 

[Max]

Flashphoner already supports this feature, but functionality is pretty weak, I would need to be able to "Pause" the video and restart when I need, right now, once you add the live translation of the OD video in the server, the video will start playing behind the scenes and doing the whole process you have suggested whilst live is not particularly smooth as it takes time to load making the process clunky.

Unfortunately, VOD does not support pausing at all. You can only start VOD live stream from the beginning of the file or stop it.
A workaround is to split VOD file to a small fragments and play them subsequentally, in this case you can stop playback and start it again from a closest fragment.

Also, when I add a stream live to the mixer there is a lag between the time I push the command and the time the stream loads in which a Grey Box is visible, please could you let me know if there is a way to smooth this out when adding streams to a mixer?

Mixer (or player) waits for the first keyframe to start VOD stream playback. So you have to prepare VOD files by reencoding them with ffmpeg for example:

ffmpeg -i VODfile.mp4 -c:v libx264 -preset ultrafast -g 60 -filter:v fps=30 -c:a aac -ar 48000 -strict -2 VODfileFixed.mp4

In this example, there will be keyframes in file every 2 seconds, so a gray box will bw displayed no more than 2 seconds.

 

[Luca]

Thank you for the response Max

The issue is as well that the grey box appears also when I add a stream from a local or remote camera and I would really love to know if there is a way to smooth this process out as we would be using the application to work as a video mixer and this grey box appearing as a placeholder whilst the video loads is pretty ugly

Please let me know
Best
Luca

 

[Max]

The issue is as well that the grey box appears also when I add a stream from a local or remote camera

Please enable periodic FIR request

periodic_fir_request=true
periodic_fir_request_interval=2000

In this case, server asks client browser to send key frame every 2 seconds.
Also make sure that your server has capacity enough for mixer to work: at least 2 CPU cores per one mixer + 2 cores reserved for other tasks. So the server should have 4 CPU cores to run one mixer simultaneously.

 

[Luca]

Thank you Max

Unfortunately(even after applying your suggested changes) it is still happening, is there a way I can make that transition smoother? change that grey colour? apply a video transition?

Any help would be much appreciated

Thank you
Best
Luca

 

[Max]

Please clarify your flow:
1. Start the mixer by REST API /mixer/startup
2. Play the mixer stream (should be black box by default)
3. Publish WebRTC stream from camera
4. Add the stream to mixer by REST API /mixer/add
Is that right?
On what step do you see a gray box?
We can't reproduce this in a latest WCS build 5.2.1329, so please update and test again.

 

[Luca]

Hi Max

your process description is correct, that's how I am doing it

Below is the link to a loom video where I demonstrate when the grey box briefly appears

localhost:3000 - 28 July 2022

Use Loom to record quick videos of your screen and cam. Explain anything clearly and easily – and skip the meeting. An essential tool for hybrid workplaces.

www.loom.com

This is at step 4 of your process

Please le me know if there is anything I can do to mitigate the appearance of these grey boxes

Best
Luca

 

[Luca]

Hi,

Any updates on my question above please?

Thank you
Best
Luca

 

[Max]

Thanks. We were able to locate the gray background on your video. We would need a bit more time to reproduce such effect on our env.

0:04 second

0:22 second

0:25 second

 

[Max]

Hello,

Ticket WCS-3564 has been submitted for removing the "grey box", we'll notify in this thread about an update.
Meanwhile, this setting can be tried as workaround to conceal the box (to change gray to a different color): mixer_text_background_colour.
The setting is for text background, but in this case it also is applied.

 

[Luca]

Hello,

Ticket WCS-3564 has been submitted for removing the "grey box", we'll notify in this thread about an update.
Meanwhile, this setting can be tried as workaround to conceal the box (to change gray to a different color): mixer_text_background_colour.
The setting is for text background, but in this case it also is applied.

That is great Max, thank you very much, I am looking forward to hear about the change.

P.s. it could be great if it would be possible to implement some sort of basic video transition when a user is activated in the mixer so to make it look more professional and more like a video mixer rather than hard cut, but removing the grey box( or the initial frame that causes the box) would be already an improvement

 

[Luca]

Hello,

Ticket WCS-3564 has been submitted for removing the "grey box", we'll notify in this thread about an update.
Meanwhile, this setting can be tried as workaround to conceal the box (to change gray to a different color): mixer_text_background_colour.
The setting is for text background, but in this case it also is applied.

@Max Is there any ETA for this so we can plan accordingly? if not please let me know so we can think about some workaround

Thank you in advance
Best
Luca

 

[Max]

We do not provide ETA on forum tickets unless they are crictical and concern the most of customers. May be next month.

 

[Max]

Good day.
We fixed the issue in build 5.2.1359. Please update WCS and set

mixer_show_separate_audio_frame=false

then restart WCS. After that, the grey box will not be displayed when stream is added to a mixer.

 

[Luca]

@Max That is an amazing achievement, thank you very much for the speedy implementation