AVChat Software Product Blog

You want to find out what version of Red5 is running on your server?

There are a few ways:

1) Look at the Red5 welcome page on port 5080.

To see the welcome page just go to http://yourred5server.com:5080 in your web browser. It’s not the most accurate but it’s the fastest and you don’t need access to the Red5 installation. Here are the welcome screens for different versions.

Red5 0.8 welcome page:

Red5 0.9.1 welcome page:

Red5 1.0 RC1 welcome page:

2) Look in docs/changelog.txt

Look in the Red5 installation folder/docs/changelog.txt . You will immediately see the Red5 version there:

3) Pay attention to the Red5 startup log

During startup, Red5 will show the Red5 version, here is where to look when starting Red5 standalone on Windows:

4) Look in log/red5_service.log

When starting Red5 as a service on Windows it will create a new log file: Red5 installation folder/log/red5_service.log . In it you will find the Red5 startup log mentioned above and thus the Red5 version.

You know any other way? Post the method in the comments section below.

We’ve made a little test today with the latest version of AVChat (1059) which has some optimized media server file for Red5.

Old Pentium M @ 1,7Ghz with 1G of RAM we used

1) We’ve installed Red5 0.8 on an old Toshiba M70 laptop with these specs:

• Pentium M 1.7Ghz (FSB:400Mhz with 2Mb of 2nd level cache)
• 1G DDR2 RAM
• 60GB HDD @ 5400rpm
• 100Mbps Intel network card
• Ubuntu 10.04 LTS

which is connected to our LAN via wire.

2) Once Red5 was up and running on the laptop, we used an internal flash app named “AVChat Virtual User” to create load on the Red5 server! This app creates a lot of virtual users, once each user is created it connects to the avchat30 app on the media server. Once connected  it starts  generating the  kind of  load that a normal user would generate: sending text messages, changing status (idle, online), etc… . These virtual users are not able to stream/view video that’s why this quick test today covers AVChat 3 in text chat only mode.

AVChat Virtual User (not much to it right now)

We will release this app when we polsih it so that anyone can test their own servers!

3) With AVChat Virtual User we’ve gradually connected 550 users (100 -> 450 – >550) and observed the load on Red5.

To monitor Red5 we’ve used several tools:

• Java VisualVM: http://download.oracle.com/javase/6/docs/technotes/guides/visualvm/index.html
• top command on the laptop running Ubuntu/Red5 : http://manpages.ubuntu.com/manpages/lucid/man1/top.1.html
• Ubuntu System Monitor

4) The results: CPU usage

CPU Usage

5) The results: Memory consumption

Memory consumption

6) Conclusion:

• a user connecting generates more CPU usage than a user that is already connected
• Red5/AVChat 3 uses about 6-7Mb of RAM for each 100 users (in addition to the memory used by Red5 by default)
• the cheapest VPS servers (256Mb of RAM) can hold a few hundred users online!
• this server would hold 1000 users (in text chat mode) before reaching 80-90% CPU usage!
• in a real world scenario you would not have the peak CPU usage caused by connecting 100 very ast ( AVChat Virtual User app connecs 1 user every second )

This is by no means an attempt  to squeeze as much performance as we can out of this server! There are many ways one cand do that first being the choice of OS.

Note: this is not a clear reflection of real world usage as video creates a lot of load on the media server! The video usage on the server creates a lot more load than the number of users online!

Later edit: for tips on how to improov the performance of AVChat on Red5 see this thread on our forum.

The latest build of AVChat 3, made available for download today, packs some awesome new features:

• Tool tips on most buttons in the UI.
• Better UI (you can now re size your cam and the users list, other cams are now floating on top of the text chat area,cam borders are drawn correctly, slightly skinnier interface with default padding set to 6px).
• YouTube videos now play (again) in the actual YouTube player.
• Added option in the UI to show join/leave messages in the text chat.
• Lots of small updates for the text chat (proper html encoding for html characters, better detection/highlight mechanism for links, in some cases text chat would go over YouTube videos/pictures previews).
• Some small changes to the upload mechanism in php to go around some wierd web server security settings we’ve met : “http” not allowed in GET variables, not even HTML encoded !!!
• Added a new video/audio quality profile for 768kbits/s streams .
• Ghost users should now be detected and disconnected in max 17 seconds on all 3 media servers.
• Changed the way the fps, free time, nr of viewers shows up in the cam areas.
• Clicking the [Add IT] buttn in the YT submit button now adds the video directly.
• Spaces in usernames are not replaced by _ anymore.
• New option in avc_settings.xxx to disable YouTube previews.
• Added memory usage display (off by default, you can turn it on from avc_settings.xxx)

and bug fixes:

• The info  about who is someone watching visible in admin.swf was not exact all the time.
• When cliking ACCEPT/DENY for someone’s request to your private stream some wierd text would fill up the text chat input box (bug introduced in build 609).
• Window padding value in style.css now actually works.
• Sorted out some sorting issues for the users list.
• When a  YT movie preview was shown in the chat the whole movie was downloaded even tough you weren’t watching it.
• private streams were not working on Wowza 2 (they were on Wowza 1.7)!

and some updates to security too:

• Added the possibility to add an ip range for the ips from where admin.swf is allowed to connect.
• Admins now see the ip of each user in the text chat, you can double click the ip to select it.
• The allow localhost connections option is now available for all 3 media servers: Wowza, FMIS, Red5.
• The Rooms List in admin.swf  now shows the ip of the creator of the room.
• Admin can now enter closed rooms.

How to get the new AVChat 3 release

You can obtain the latest AVChat 3 build by downloading the software again ( using the download link from the delivery/trial email) and:

• doing a clean install
  or
  
• overwrite all the old files including the FMIS/Red5 server side files and the translation files

Changes:

• small changes to the source code
• added Red5 0.9 server side files, however audio recording in Red5 0.9 seems to be broken. None of the resulted .flv files played back properly in Flash Player or in deskop flv players. Running the flvcheck tool (shipped with FMIS) on any .flv file recorded using Red5 0.9 brings out the following error: Error -11 Found backward timestamp. However the latest Red 5 trunk version (rev 4047 right now) works properly.
• build 63

So, if you’re into audio recording with Red5, use Red5 0.8 or skip Red5 0.9 and use the trunk version.

How to get it:

• just download the software again using the link you got in the email from contact@avchat.net when purchasing it!

http://flvar.com/

Red5 0.8 support

We are glad to announce that AVChat 3 for Red5 0.8 is now available.

Only Red5 0.8 is supported! We do no plan to support Red5 0.7 or earlier versions because  0.8 is the most stable Red5 release yet and we encourage everyone to upgrade their Red5 installation if they have not done so already!

To purchase AVChat 3 now visit the purchase page! When you purchase AVChat 3 you will now get both the FMIS and the Red5 media server files.

Other Enhancements

• after logging in the chat, when joining the first room the welcome message is shown at the bottom of the existing text chat (history)
• you can now change the amount of lines of previous text (history) chat that you see when joining a room
• the code in avc_settings.asp has been changed from JavaScript to vbScript
• default text used throughout the software is now Tahoma instead of Verdana. Verdana caused RTL text to be displayed in an awquard way!
• you can now configure the path to the .xml language file (translations) in avc_settings.xxx (languagefile variable)
  
• you can now configure the software to automatically start broadcasting the users webcam and mics only if they have a webcam (if they have only a mic they dont start braodcasting, autoStartMyCamAndMicOnlyIfIHaveACam variable )
• if you post a link to a image, the image will be automatically shown in the text chat

Bug fixes:

• if you started braodcasting your webcam/mic while you were in two rooms, your broadcast could fail and other users could not see/hear you.
• the external users list was not updated when a user started his webcam/mic
• freevideotime=-1 in avc_settings.xxx now disables the free video time limit
• the history shared object for each room became large over time and joining rooms took too long
• the SEND text chat button did not have a translation in the language file
• When using the Joomla component  or Drupal module you could not take a webcam fullscreen
• when clicking the U/I/B buttons the text chat input box does not loose focus anymore

How to get the new AVChat 3 release

You can obtain the latest AVChat 3 files by downloading the software again using the download link from the delivery/trial email. You will automatically download the latest build which includes all the bug fixes and feature enhancements mentioned in this post and the Red5 0.8 server side files. After downloading them do a clean install or overwrite all the old files including the FMS server side files!

What’s next?

We will start working on adding support for Wowza.

We are also gathering feedback on what major/minor features to add so if you want any features implemented send us an email at contact@avchat.net or leave a comment!

This post is part 3 of our 3 part series on recording high quality Flash video over slow connections.

In theory whenever someone is trying to use a flash video recorder to:

• record audio/video at a  data rate higher than the upload connection to the media server (Red5, FMS, Wowza, etc..) allows,
• record audio/video at a data rate higher than 1Mbit/s (which seems to be the upload/streaming limit in Flash Player)

Flash Player will buffer the audio and video data until it can be properly sent to the video server.

But what really happens is this: it starts buffering the video data and keeps sending the audio data to the media server.

It does that because Flash Player thinks all streams are live (even those specifically destined for being recorded) so it tries to at least keep the audio “live”, if its not possible to keep both audio+video “live”.

What happens now is that the video frames will arrive at the media server:

1. later than the corresponding audio frame
2. arrive after the media server has already written the corresponding audio frames to the .flv file
3. never arrive, because Flash Player has flushed the client buffer that was holding the video data

This can cause several issues in the final .flv file:

• missing or little video data across some sections
• sudden increases in video frame rates (the video plays in a “fast forward” way because several video frames finally reach the server as a bundle)
• flv files with static video, normal audio playback and the rest of the video data grouped at the end
• flv files with large areas where you can not seek (because there is only audio data in those areas)
• out of sync audio and video

To solve this issue, some media servers are now waiting longer for the video data to come from the client (flash video recording software) before writing the existing audio data to the .flv file:

• Wowza Media Server and  Flash Media Interactive Server 3.5 both solve this issue out of the box.
• Flash Media Interactive Server 3.0 can also solve this issue by adding some custom/hidden XML tags to Server.xml.
• Red5 up to 0.9.1 has this issue and a bug has been submitted which you can follow here here.
• Red5 1.0 attempts to fix this issue to by exposing a save data to flv treshold variable, more info on that here.

This concludes our 3 parts (part 1, part 2) series on recording high quality audio and video files over slow connections.

Next I think we will talk about increasing the audio and video quality for the average user!

28 April update: updated with latest available information on the issue and link to Red5 1.0 RC1 fix.

This is part 2 of our 3 part series on recording high quality Flash video over slow connections.

As explained in the first part, a big buffer should be used in the recorder flash app so that the video and audio data has where to wait before its turn comes to travel to the media server.

When the user stops the recording (by pressing a STOP button for example) most probably there still is some audio & video data in the buffer, data that has not been sent yet to the media server.

Part 2: wait for the audio and video data to reach the media server before we display any SUCCESS message to the user

Otherwise you will most probably end up with videos with missing endings and frustrated users.

Heres how stopping a recording unfolds in our flash video recorder:

1. STOP button is pressed (or recording time limit is reached)
2. we stop capturing data from the cam and mic
3. we display a SAVING VIDEO message until the buffer is empty (all the data in the buffer is sent to the server)
4. when the buffer reaches 0 we finally display the recording saved properly success message.

In code (as2) Step 2 translates in ns.attachAudio(null) followed by ns.attachVideo(null).

Step 3 and 4 (detecting when all the data has reached the media server ) can be done in several ways but we listen for a NetStream.Buffer.Empty or NetStream.Record.Stop net status event fired while ns.bufferLength == 0 .

In as3 the procedure should be similar.

In part 1 we’ve talked about using a big buffer on the client side.

In part 3 we will talk about getting the media server to properly save the video and audio data to the HDD.

AVChat 2.1 and AVConference 1.1 are now fully compatible with the free open source Red5 media server. Absolutely all the features in both softwares are implemented in the new Red5 versions.

Red5 is a free, open source, Java based, alternative to Adobe’s Flash Media Server. Altough the server is in pre-alpha there are many production-ready applications that work on Red5 and many have chosen to use Red5 because its free and open source.

To install Red5 you need a dedicated server. You can not install Red5 on a shared hosting plan. Red5 is available for both Windows and Linux. You can find more info about it here:http://osflash.org/red5

Until now AVChat 2 and AVConference worked only with Adobe’s Flash Media Server.

To purchase AVChat 2 or AVConference on Red5 email us after the purchase and let us know you want the Red5 version.

If you have already purchased AVChat 2 or AVConference email us and we will send you the proper Red5 files for your licensed domain.

All tutorials and support material on the website will now be updated to include Red5 specific info.