Vod-live questions

[Reebo]

Hi,
2 question about vod-live

1) Can I create a playlist of mp4 file to streaming sequentially?
2) Can I load a vod-live or a playlist directly from url (on demand) without start a rest-api streaming?

Thanks in advance.

Marco

 

[Max]

Good day.

1) Can I create a playlist of mp4 file to streaming sequentially?

Unfortunately, no. You should concat the required files to the one using ffmpeg for example.

2) Can I load a vod-live or a playlist directly from url (on demand) without start a rest-api streaming?

Yes. You can play a VOD-live stream directly from browser as described here

 

[Reebo]

Thanks for the answers.
What, in your opinion, is the best way to run an mp3 playlist controlled by a web client on multiple web clients?

Many thanks for your support.

marco

 

[Max]

What, in your opinion, is the best way to run an mp3 playlist controlled by a web client on multiple web clients?

First, all the files should be converted to MP4 with the same codec (AAC), channels count (stereo), sample rate (48 kHz to prevent excessive resampling)
1. Set the following parameter in WCS configuration file flashphponer.properties

mixer_idle_timeout=10000
opus.encoder.bitrate=128000

2. When web client is connected and playlist is combined, create an audio only mixer for that client

POST /rest-api/mixer/startup HTTP/1.1
Host: wcs:8081
Content-Type: application/json

{
    "uri":"mixer://clients_playlist",
    "localStreamName": "clients_playlist",
    "hasVideo": false,
    "hasAudio": true
}

and play the stream "clients_playlist" in clients browser
3. Publish the first playlist item

POST /rest-api/vod/startup HTTP/1.1
Host: wcs:8081
Content-Type: application/json

{
    "uri":"vod-live://first_item.mp4",
    "localStreamName": "first_item"
}

4. Add the first item to the mixer

POST /rest-api/mixer/add HTTP/1.1
Host: wcs:8081
Content-Type: application/json

{
    "uri":"mixer://clients_playlist",
    "remoteStreamName": "first_item",
    "hasVideo": "false",
    "hasAudio": "true"
}

5. Periodically check if first_item is finished to play

POST /rest-api/vod/find HTTP/1.1
Host: wcs:8081
Content-Type: application/json
 
{
    "localStreamName": "first_item"
}

This query will return 404 when stream is finished
6. Add the next item to the mixer and so on
7. When client stops the play back, stop the mixer

POST /rest-api/mixer/terminate HTTP/1.1
Host: wcs:8081
Content-Type: application/json

{
    "uri":"mixer://clients_playlist"
}

 

[Reebo]

Ok thanks!

and on client side, what’s player can I use for crossing browser esperience? (we serve more web clients)

can I play stream before it was publishing? (Starting automatically when moderator start playlist)

 

[Max]

and on client side, what’s player can I use for crossing browser esperience? (we serve more web clients)

There is Player example, please see its code on GitHub. You can build custom player based on the code.

can I play stream before it was publishing? (Starting automatically when moderator start playlist)

The stream should be published on WCS server before playing it, othewise client will receive an error.

 

[Reebo]

First, all the files should be converted to MP4 with the same codec (AAC), channels count (stereo), sample rate (48 kHz to prevent excessive resampling)
1. Set the following parameter in WCS configuration file flashphponer.properties

mixer_idle_timeout=10000
opus.encoder.bitrate=128000

2. When web client is connected and playlist is combined, create an audio only mixer for that client

POST /rest-api/mixer/startup HTTP/1.1
Host: wcs:8081
Content-Type: application/json

{
    "uri":"mixer://clients_playlist",
    "localStreamName": "clients_playlist",
    "hasVideo": false,
    "hasAudio": true
}

and play the stream "clients_playlist" in clients browser
3. Publish the first playlist item

POST /rest-api/vod/startup HTTP/1.1
Host: wcs:8081
Content-Type: application/json

{
    "uri":"vod-live://first_item.mp4",
    "localStreamName": "first_item"
}

4. Add the first item to the mixer

POST /rest-api/mixer/add HTTP/1.1
Host: wcs:8081
Content-Type: application/json

{
    "uri":"mixer://clients_playlist",
    "remoteStreamName": "first_item",
    "hasVideo": "false",
    "hasAudio": "true"
}

5. Periodically check if first_item is finished to play

POST /rest-api/vod/find HTTP/1.1
Host: wcs:8081
Content-Type: application/json

{
    "localStreamName": "first_item"
}

This query will return 404 when stream is finished
6. Add the next item to the mixer and so on
7. When client stops the play back, stop the mixer

POST /rest-api/mixer/terminate HTTP/1.1
Host: wcs:8081
Content-Type: application/json

{
    "uri":"mixer://clients_playlist"
}

Hi Max,
all seems to works fine, but quality seems worse that direct vod streaming... It's correct?

 

[Max]

all seems to works fine, but quality seems worse that direct vod streaming... It's correct?

Please clarify how much worse? Are there some clicks, pauses and so on in mixer output stream?
Please check if you set opus.encoder.bitrate parameter as we recommended.
Also, check server CPU load using top for example. If CPU load is constantly high, consider to upgrade the server to more CPU cores (for example, from 2 cores to 4).

 

[Reebo]

the same vod, launched alone

"rest-api / vod / startup"
{ "uri": "vod-live: //output.mp4", "localStreamName": "test" }

feels great.
But
The same file added to the mixer, loses a lot of quality (bass, clarity)

Both play with same player.
ps. set opus.encoder.bitrate 128000 and some test with 256000 and 512000 same bad result.

Thanks in advance.

 

[Max]

We tested on latest WCS build 5.2.912 but did not found a viewable difference.
Please try to increase opus encoder complexity from 10 by default to 20 for example

opus.encoder.complexity=20

and check.
If this does not help, please provide SSH access to your server and a test file (put it to media folder) using this private form, we will check.

 

[Reebo]

I upgrade to 5.2.9.12 and set encoder complexity but it doesn't works.

I send you a private form.

Many Thanks

 

[Max]

Unfortunately, we cannot connect to your instance:

Please provide a working credentials.

 

[Reebo]

I'm sorry.
Try now please.

Marco

 

[Max]

We checked the case on your server and reproduces the issue in our test environment. Seems like mixer audio output is playing always as mono.
We raised the ticket WCS-3098 to investigate this and let you know results here.
Also we recommend you to use audio only files for audio only streaming case, to prevent excessive video encoding and to decrease CPU load.

 

[Reebo]

Ok! Thanks.

 

[Reebo]

Any news about ticket WCS-3098?
Where can I see the progress?

thanks,
Marco

 

[Max]

Good day.
We increased mixer playback quality, but still playing as mono. Will let you know when find a fix.

 

[Max]

We fixed mixer audio output quality issue in build 5.2.919, please update and check. There is no significant difference playing your test file directly and in mixer.

 

[Max]

Good day.
We added the parameter to enable stereo audio support in mixer since build 5.2.922

audio_mixer_output_channels=2

Please update and check.
We also recommend to convert audio to sample rate 48000 Hz.