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thaischumi

Transcoded streaming has problem with high latency (ping) connections

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thaischumi

Hello,

All versions of DVBViewer Recording Service have a very weird bug in transcoded streaming (http:/ip:8089/flashstream/stream.flv....), the possible maximum streaming bitrate is highly affected by connection latency (ping) even though you have high speed connection.

 

I have connection with 40Mbps uplink anh I have no problem with streaming over Internet in direct stream mode (http://ip:7522/upnp/channelstream/xx.ts), yeah, I can watch HD channels with bitrate over 15Mbps in direct stream mode from another internet connection without any problem. But with transcoded streaming I am not able to watch if i have streaming bitrate over 3Mbps.

 

I found out that is affected by connection latency, when I on purpose rise the latency of network by NetBalancer to 100ms, watching transcoded streams with bitrate over 1Mbps is nearly impossible but direct streams still work fine.

 

Any help?? Are there some hidden settings that can increase buffer size on the server side?

Thanks very much,

 

Edited by thaischumi

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Griga

Never heard of this issue before.

 

8 hours ago, thaischumi said:

Are there some hidden settings that can increase buffer size on the server side?

 

You can try to change the default delay values by tweaking the presets in the file ffmpegprefs.ini, see installation folder (! where DVBViewer.exe is), config sub-directory, e.g. like this:

[Flash Mid 1200 kbit]
{....}
Ext=.flv
Delay=4000

The delay specifies how long the RS waits until it begins to deliver transcoded data. The default value is 2000 ms. Increasing the value means more buffering on the server side or more reading ahead on the client side (depends on the client behaviour).

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thaischumi

I tried to modify ffmpegprefs.ini as much as possible but it didn't help.

 

Arcoding to this diagram I think problem is in the Web/transcoded streaming server:

dvbserver.thumb.png.02ca2ddbfe57c441399e412947c87365.png

 

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Griga
9 hours ago, thaischumi said:

But with transcoded streaming I am not able to watch if i have streaming bitrate over 3Mbps.

 

What happens? No picture / audio at all? Playback disturbed in some way? Did you modify the FFmpeg presets?

 

The maximum buffer capacity between FFmpeg input to the server -> server output to the client is approx. 1.4 MB. This means 2.3 s with a 5 MBit/s stream. Maybe too little in your case?

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thaischumi
26 minutes ago, Griga said:

 

What happens? No picture / audio at all? Playback disturbed in some way? Did you modify the FFmpeg presets?

 

The maximum buffer capacity between FFmpeg input to the server -> server output to the client is approx. 1.4 MB. This means 2.3 s with a 5 MBit/s stream. Maybe too little in your case?

It looks like I have slow connection (but not), it play few seconds then pause few seconds (buffering).

Edited by thaischumi

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Griga

If the buffer is not large enough I'd rather expect drop-outs due to data loss.

 

Have you already checked the server CPU load? Transcoding high bitrate streams is quite demanding.

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thaischumi
3 hours ago, Griga said:

If the buffer is not large enough I'd rather expect drop-outs due to data loss.

 

Have you already checked the server CPU load? Transcoding high bitrate streams is quite demanding.

Cpu load is OK.

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Griga

Strange. Are you still using the RS 1.33.2 or have you already upgraded to the DVBViewer Media Server 2.0?

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thaischumi
2 hours ago, Griga said:

Strange. Are you still using the RS 1.33.2 or have you already upgraded to the DVBViewer Media Server 2.0?

I'm still using RS. Could you tell me who is programmer of RS and MS?

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majstang
48 minutes ago, thaischumi said:

I'm still using RS. Could you tell me who is programmer of RS and MS?

Development of RS is discontinued. So if this pans out to be a bug there is little to none chance you will get it fixed. Then you will have to buy DMS

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Griga
53 minutes ago, thaischumi said:

Could you tell me who is programmer of RS and MS?

 

Me :) Inherited from Lars, who unfortunatly died in 2013.

 

The Media Server 2.0 contains several enhancements for transcoded streaming, but nothing directly related to the issue that you are encountering.

 

So what can we do now? For testing purpose I could provide a RS version with a considerably enlarged buffer between FFmpeg input and server output in order to find out if the buffer size can cause such issues. Generally I think it should be larger. 1.4 MB are nothing nowadays. However, there is no guarantee that it will help in your case.

 

Please note that I can only provide a RS 1.33.2 test binary. So you should update to DVBViewer Pro 5.6.4 and RS 1.33.2 first, if not yet done. These versions are still available in the download area -> Older Versions section.

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thaischumi

I have DVBViewer pro 6.0.1, but RS 1.31.0 because later versions are messed with authentication over WAN. Ofcourse I tried 1.33.2.1 but it didn't help so I have come back to 1.31.0.

 

If the editing the binary isn't difficult, could you fix the version 1.31.0 too? Thanks very much.

Edited by thaischumi

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Griga
39 minutes ago, thaischumi said:

If the editing the binary isn't difficult, could you fix the version 1.31.0 too?

 

Sorry, not possible. Only 1.33.2. If 1.31.0 is a must for you, nothing can be done.

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