Re: Voice Quality test, Demo.bigbluebutton and bbbhost demo

[Zeeshan Ali Shah]

Hi , Any comment on below , since i also faced the same on my own installation..


Zeeshan

On Tue, Mar 20, 2012 at 10:12 PM, Zeeshan Ali Shah <javac...@gmail.com> wrote:

Hi,

I installed beta 4 but found  not good quality of voice. so i checked the

1) demo.bigbluebutton
and
2) bbbhost demo   of latest installation 0.8 beta-4


Here are samples both from Speaker and Client for both .

It seems that Voice quality is not good . Any suggestion ? since i have same situation on my install. but test it on demo just to confirm that his problem is not specific to my install .


kindly listen in fulll to get exact quality..

any suggestion ?

BR

Zeeshan

[Zeeshan Ali Shah]

Hi , Any comment on below , since i also faced the same on my own installation..


Zeeshan

[Fred Dixon]

Hi Zeeshan,

Can you be more precise on 'quality is not good'.   How are you testing the audio?  To test audio, we recommend you open two different browsers and log into the BigBlueButton server from both browsers.  Join the audio in each, then mute yourself in one.  Now, when you speak, you'll hear you voice going from one client, to the server, and back in the others.  This will give you a sense of the round-trip for audio.

Can you go to 

   http://www.speedtest.net/

and post the results.

To understand the environmental conditions that will affect audio, we can break it down into these parts:

(1) Speed of the user's computer

(2) Capacity of BigBlueButton server

(3) Upstream bandwidth from user's computer to BigBlueButton server

(4) Amount of packet loss in upstream connection

(5) Downstream bandwidth to user

(6) Packet loss in the network

(7) Dropping packets by BigBlueButton

With today's computers (1) is not an issue.  We recommend running BigBlueButton on a dedicated server, which is demo.bigbluebutton.org, so (5) is not an issue.  

If your run BigBlueButton within a LAN environment, you should experience low latency and audio that is clear and without breaks or interruptions.  On a LAN you have good upstream, downstream, and low packet loss (3-5).

Over the Internet, the networking is different.  The latency between you and the server will determine the length of time needed for the packets to reach the remote BigBlueButton server.  The Flash environment in the browser restricts applications to using TCP/IP (UDP is not available).  This means, any packet loss in the network (6) will cause the BigBlueButton client to re-send the audio packets.  If the upstream network connection is good, say 1 Mbps and the packet loss is low, then you should experience good audio.

However, if the upstream bandwidth is much lower and there is increased packet loss, then the resending of TCP/IP packets will take longer, and eventually the packets will reach the BigBlueButton server too late.  If packets are arriving late, the BigBlueButton server will drop them.   Richard can give the precise algorithm, but the point is your going to start experiencing gaps.

Many people compare BigBlueButton to skype, which is a very good system for two-way communication.  It's a binary application that uses peer-to-peer to send UDP packets.   If you are having problems with Skype, BigBlueButton will not be able to do better as it's packets are TCP/IP and susceptible to resending.

Zeeshan, we've done a lot of work in BigBlueButton 0.8 to improve the audio, but we can only work on the client and the server software -- we have no control over the network in between, nor the restriction to use only TCP/IP.   

If your users are on low-speed internet connections with packet loss, the audio will likely have empty gaps, fluctuate, and be hard to understand.   

We recommend you do not use BigBlueButton in such scenarios.  

Regards,... Fred

-- 
BigBlueButton Developer

http://bigbluebutton.org/
http://code.google.com/p/bigbluebutton

BigBlueButton on twitter: @bigbluebutton

 

For (2), can you go to speedtest.net and share the results 

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[Zeeshan Ali Shah]

I tried using bigblubutton demo server .. see samples .. 

[Zeeshan Ali Shah]

 i think this is precise enough . kindly play whole files to get the quality .. and kindly tell  me if something missing

Two files from Speakers and  Client are attached...

Zeeshan

On Wed, Mar 21, 2012 at 2:00 PM, Zeeshan Ali Shah <javac...@gmail.com> wrote:

I tried using bigblubutton demo server .. see samples .. 

 i think this is precise enough . kindly play whole files to get the quality .. and kindly tell  me if something missing

Zeeshan

[Fred Dixon]

Hi Zeeshan,

We listened to the audio files, but can't detect any spoken audio in the second file.  Rather than playing an MP3 in the background, try logging into two BigBlueButton sessions (using different browsers), join the audio in both, and mute yourself in one.

This will be a better test as when you speak, you can hear the latency (the time between you speak and when it goes to and from the BigBlueButton server), and you can hear the quality of the audio (does it have gaps or is difficult to hear).

Do this test against a LAN computer and a remote BigBlueButton server to calibrate.   The test against the remote server will reveal the differences between the networking, load on the remote server, and your internet connection (packet loss and HTTP tunneling).

Can you go to 

   http://www.speedtest.net/

and post the result as well.  

Again, to set expectations, if you've got a working BigBlueButton server, but the audio is not good compared with a similar server on the LAN, the problems are very likely in the networking between, not the software itself.  See previous post for more detail.  

Regards,... Fred

-- 
BigBlueButton Developer

http://bigbluebutton.org/
http://code.google.com/p/bigbluebutton

BigBlueButton on twitter: @bigbluebutton

[HostBBB.com]

Zeeshan,

 

I listened to the clips....the popping that occurs is from jitter, packet loss most likely,  meaning your internet connection, or pc cpu  has a lot of variation in timing of received packets that causes the codecs to go crazy during there decoding.

 

Also,  these codecs are designed for normal voice speech  300-4000hz and optimized to send normal dicussion.   Any time you send music, or sounds that extend that range the quailty is degraded.

 

That source of  that test clip has some audio effects, the person chanting, singing has some  reverb or sound effects at higher pitch as input only making it worse.

 

Try sending a constant tone 1000hz thru your system and see if it can record the tone with no issues for 5 minutes.  Will give you a good indication of your end to end performance with the client/server being just a small piece of the equation.

 

We run a live 27/7 Talk show network with freeswitch/icecast integrated with bbb  on c1.medium instances and the audio performance is great.

 

regards,

Sephen 

hostbbb.com

[Fred Dixon]

Hi Stephen, 

Thanks for sharing your experiences and feedback.  

> We run a live 27/7 Talk show network with freeswitch/icecast integrated with bbb  on c1.medium instances and the audio performance is great.

 

Members of this forum should read this comment with a grain of salt.

We've learned (the hard way) to carefully state any level of quality for BigBlueButton's performance.  When I first read the above, I thought "BigBlueButton runs great on an EC2 c1.medium" and "the audio performance is great" -- but that isn't going to be true for everyone in the world.

We (strongly) suspect that if Zeeshan runs BigBlueButton on an EC2 (or anywhere on the internet), there will be still be problems with audio due to network bandwidth, latency, and packet loss.   The demo.bigbluebutton.org server runs on a high-bandwidth network, but it's in NA, and Zeeshan was still having problems with the audio.

The grain of salt is you need to take into account how your users are going to connect to BigBlueButton and test with them.  Your experience's with BigBlueButton's audio (and its other capabilities) will depend partly on their connection to the server.  See

   http://code.google.com/p/bigbluebutton/wiki/FAQ#What_are_the_bandwidth_requirements_for_running_a_BigBlueButton

Regards,... Fred

-- 
BigBlueButton Developer

http://bigbluebutton.org/
http://code.google.com/p/bigbluebutton

BigBlueButton on twitter: @bigbluebutton

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[Zeeshan Ali Shah]

Hi All ,
I really admire your work and effort .

My ambition with the test was not to raise fingers rather provide constructive feedback specially when bbb in dev stage.  That is why i did the test because i care about bbb success. 

sorry if it hurt anyone , but again my ambition was only to deliver the results.

I selected demo setup to avoid any loophole in my own installation..



BR

Zeeshan

[Fred Dixon]

Hi Zeeshan,

Don't worry!  We *appreciate* your taking the effort to report problems.  BigBlueButton is a complex system, and our belief is the more we can educate others (and learn from them as well) about the system, the better it becomes.

It would be great if you could go to

   http://speedtest.net/

and give us the results from testing your connection.  As you can see from this thread, we believe part of the problem for the audio is your connection, but we don't have any data on your internet connectivity.

Regards,... Fred

-- 
BigBlueButton Developer

http://bigbluebutton.org/
http://code.google.com/p/bigbluebutton

BigBlueButton on twitter: @bigbluebutton