BuenaVista Videoconferencing System
User’s Guide for the Windows 95/NT Version 3.0
Tom Stachowiak
Table of Contents
Your system must meet following requirements to ensure correct operation of BuenaVista.
Windows 95/NT 4.0
For DX version of BuenaVista: Microsoft
DirectX 5.0 package
Appropriate drivers for audio and video
cards
A networked Pentium 133 MHz PC (Pentium 200
MHz is recommended for users using video cameras)
Minimum 32 MB of RAM (recommended:
64MB for Windows 95/98, 128MB for Windows NT)
2 MB of disk space (4MB for TANGO
Interactive version)
Network card or a modem supporting IP
protocol
Audio card supporting 8 kHz 16 bits
sampling (full duplex support recommended) The product has been tested with the following audio cards:
SoundBlaster 16 and SoundBlaster64
Ensoniq Soundscape Vivo
Speaker/headphones
Microphone
Video capture card (optional) supporting
RGB 24 and/or YUV9 format. The product has been tested with the following video capture cards or digital camaras:
Intel Smart Video Recorder III
Winnov Videum products, including laptop
digital cameras (this product integrates audio capture)
Panasonic Eggcam
Vicam USB digital camera
Camera or other video source (optional)
Hardware and Software Configuration
In order to effectively utilize BuenaVista it is very important to properly configure audio drivers. After successful installation of audio card drivers it is essential to check their proper operation. The best way to do this is by using standard Windows audio tools such as Media Player and Sound Recorder, which can be accessed through Start/Program/Accessories/Multimedia/ menu. In case of any problems, first check the driver setting with Volume Control (placed at the same location). If manipulating standard driver setting does not improve the situation, please refer to your audio card manual or contact the audio card vendor. If basic Windows tools do not operate properly, it will be impossible to use BuenaVista.
Since Windows audio architecture allows only one application to capture audio device, you must quit any application utilizing audio before you start BuenaVista. Otherwise, after establishing the session, BuenaVista will terminate displaying appropriate error message.
Video card is an optional element of the videoconferencing system. Without video card, you will be able to communicate through the audio channel and you will receive incoming video streams from other conference participants. However, you will not be able to send the video stream from your camera. Pressing the camera button on a PC without the card displays a warning.
Since there are many video formats available through different video capturing cards, BuenaVista supports only the most popular ones, RGB 24 and YUV9, and any frame size over 176 x 144. Your card must support at least one of those formats to work correctly with BuenaVista. Moreover, your video capture driver must be set to one of those formats before BuenaVista can use video capture capabilities. Otherwise, appropriate message will be displayed upon pressing the camera button. To ensure the correct operation, when starting BuenaVista for the first time, go to the Edit/Options menu, choose Video tab and press Video Format button. The appearance of Video Format window is dependent on the installed card and the driver. You must set appropriate format and size and close both Video Format and Options windows before you proceed.
BuenaVista for TANGO Interactive
BuenaVista for TANGO Interactive comes automatically with your TANGO Interactive installation. Please, refer to the TANGO Interactive documentation on how to install this application.
Note:
For the BuenaVista DX version you need to have Microsoft DirectX 5.0 installed prior to the BuenaVista/TANGO Interactive installation.
Using BuenaVista
The main panel of BuenaVista consists of three major components: session control (‘Participants’ frame), audio control (‘Control’ frame) and video control (Camera button). In addition, there is a status box that shows variety of messages related to BuenaVista operation. The TANGO Interactive version does not include session control component since session setup is performed through TANGO Interactive Control Application.
Figure 1 BuenaVista Main Panel
Call Button – allows direct session creation by sending invitation, invokes ‘Call User’ window, where you can type the IP address of the host where invitation will be sent.
Accept/Reject Buttons – are activated only upon receiving a call. Not used in the ‘Auto Accept’ mode
Participant Panel – displays names and IP addresses of all session participants. Double clicking on a particular user displays additional information
Status Text Box – displays variety of messages regarding BuenaVista operation
Camera Button – initializes video capture and broadcast
Speaker/Microphone Level Indicators – show level of incoming/captured audio stream
Cut-off Level Sliders – set threshold levels for automatic switching in the half-duplex mode. Microphone slider is additionally used to control the silence level (audio samples below that level are treated as silence and not sent)
Speaker/Microphone Switch – switches between send and receive for audio in the ‘Manual Switch’ mode
Auto/Manual Switches – set audio switching modes. Manual switch mode requires the user to manually switch between audio send and receive, similar to the walkie-talkie operation. This mode is required for certain secure applications. In Auto switch mode BuenaVista will automatically switch between send and receive based on the levels of audio signal from the microphone and the network (incoming audio). This option is only useful with half-duplex cards. It should be avoided with full-duplex cards as it may lead to a lower quality of transmitted audio. The audio level thresholds used in auto switch mode are set by the "Speaker" and "Microphone" sliders above the "Auto switch" checkbox.
Note that the mode switch controls are blanked if BuenaVista is not is a session.
Options window can be accessed from main BuenaVista menu choosing Edit/Options. This window provides access to settings of all properties affecting BuenaVista operation. It is divided into three tabs: general, audio and video. Changes will be applied only after pressing ‘Apply’ (does not close Options window) or ‘OK’ (closes Options window) buttons. If you press Cancel, the changes you made will be ignored. For the user’s convenience, invoking Options window interrupt video capture/encoding/ transmission process. The process is automatically resumed after closing the window.
Figure 2 General Options Panel
Connection – determines the available network connection, It is very important to set this value properly in order not to exceed available network bandwidth
Name/E-mail address – identify the user to the Directory Service and during existing sessions; user is asked to set those values when starting BuenaVista for the first time
Directory Server – address of the server that registers running of BuenaVista
Audio Options
Figure 3 Audio Options Panel
Mode
– indicates whether your audio card supports full-duplex or half-duplex modeCompression – indicates the current audio compression option. Audio codec selection is determined based on the ‘Connection’ you selected from General Options panel
Volume/Mic Gain Sliders – allow adjusting speaker/headphones volume and microphone gain
Mute – mutes incoming audio
Mic off – switches off the microphone
Video Options
Figure 4 Video Options Panel
Video Capture Device – since PCs may be equipped with more than one video capture card, you may select the one you want to use from this menu. Remember to set appropriate video format after any changes to this selection!
Video Format/Video Source – those buttons invoke driver-specific windows control capturing parameters. Refer to your capturing card manual for details
Frame Rate – allows to control captured video frame rate; this options has direct impact on outcoming bandwidth and CPU performance, default value is chosen automatically for your network connection and CPU power; in some situations you may want to decrease it (e.g. , when you use another CPU intensive application); ‘Default’ button restores the original setting
Compression – indicates the video compression option being used
Receive Off – switches off display of all incoming video streams
Directory Service Window
This window is only available in the stand-alone version of BuenaVista. The version integrated with TANGO Interactive uses TANGO's session management mechanisms instead of the directory server.
Figure 5 Directory Service Conferences Panel
Topic List
– list of currently available conferencesParticipants List – list of participants of the highlighted conference
New Button – creates a new conference. In the pop-up window you should enter the name and the type of the conference
Delete Button – removes the highlighted conference. You can only delete conferences created by yourself
Join Button – allows joining the highlighted conference (for some types of conferences, password or authorization may be required)
Leave Button – requests leaving the current conference
This section applies only to the stand-alone version of BuenaVista. All conference management operations in BuenaVista for TANGO Interactive are performed through the TANGO Interactive control panel.
BuenaVista session control distinguishes two different modes of operation: direct session management and Directory Service supported session management. Direct session management allows inviting participants by simple typing their IP address or DNS name. Directory Service supported session management takes advantage of the BuenaVista directory server that registers all users and enables them to create and join the open or protected sessions.
In order to ensure correct operation of BuenaVista, it is important to properly initialize certain system parameters. User identification data are used both for Directory Service and for in-session identification. When you start BuenaVista for the first time, you will be asked to provide your name and your e-mail address. (BuenaVista for TANGO Interactive does not require identification since it uses appropriate TANGO Interactive information) You may change values of these data at any time through Edit/Options/General panel (see Figure 2).
Another important information is the address of the Directory Service. Initially, it is set pointing to the default server in NPAC. However, you may direct it to another server, just by changing the value of the Directory Server text field on the General Options panel (Figure 2).
Finally, the crucial parameter required to be set properly is the Connection value. Adjust its value to best match your network connection. Incorrect setting is likely to produce serious problems with the audio and video quality and to congest your network. Check the Video Control section for information about other parameters needed to be set up correctly before using BuenaVista.
INVITING (CALLING) A USER:
You are notified about receiving invitation with appropriate message in the status box and the ringing signal (manual mode only). Received invitation can be answered manually or automatically. This is determined based on the ‘Auto accept’ check box in the Edit/Options/General panel (see Figure 2). In manual mode ‘Accept’ and ‘Reject’ buttons on the main panel are activated upon receiving invitation, allowing user to make a decision. In the automatic mode all invitation are immediately accepted unless user is already in session in which case the invitation is automatically rejected in both answering modes.
Directory Service Supported Session Management
Directory Service advertises the users currently running BuenaVista and the available conferences. This way you can check who is on-line and what topics are discussed. Conferences are divided into three groups:
Open – open without any restrictions to any
users
Password protected – requiring typing the
password to enter the session
Owner controlled – requiring the authorization
from the session creator
You may either create your own session or join an existing one.
CREATING NEW CONFERENCE
Conference will be created and you will automatically become it’s participant. If you leave a conference when you are the only participant, the conference will be destroyed
DELETING CONFERENCE
Note that you can only delete a conference that you have previously created.
JOINING EXISTING CONFERENCE
LEAVING CONFERECE
Although audio control user interface may seem too complicated, in many situations it is critical to manipulate all offered options properly in order to conduct effective conference. An important thing the user needs to understand about PC audio is the concept of half-duplex vs. full-duplex hardware configuration. In full-duplex mode, it is possible to capture sound from the microphone and listen to the audio coming through the speakers at the same time. Unfortunately, many audio cards offer only half-duplex mode, where only one of those operations can be performed at any given time. Thus, it is essential to ensure proper switching mechanisms to be able to effectively communicate. However, even with those mechanisms in place, awareness of the process taking place and maintaining certain speaking discipline is necessary.
BuenaVista offers two ways of dealing with half-duplex cards. First one is the manual switching between microphone and speaker mode. In this mode user has the ability of manually switching between microphone and speaker using the button placed on the main panel (see Figure 1). This option is activated with the check box located next to the button. Although this mechanism is easy and convenient for some purposes (e.g. distance learning), in other situations "hands-free", automatic switching is more appropriate. However, taking advantage of this option requires good understanding of the mechanism and some experience in using it. Major elements controlling the switching process are the level indicators and cut-off sliders on the main panel. Switch takes place only when the level on one of the indicators is below the cut-off level and above on the other. It is crucial to set the threshold level right above the environment noise, which is common for the computer audio equipment.
In general, we discourage use of the omni-directional microphones installed in some of the video cameras. These microphones are usually too sensitive and tend to pick up disturbing ambient noise. You risk that your private conversation is overheard if you accidentally leave such a microphone open. The best solution for teleconferencing is to use a good headphones with integrated microphone.
Note:
In order to use BuenaVista effectively your audio card must be properly installed and configured. To facilitate customizing your volume and microphone sensitivity settings and other audio parameters you may invoke system audio panel directly from View/Audio Panel menu.
Taking advantage of the video capturing functionality requires proper initialization of the video card drivers. Refer to the Video Card Configuration section for details.
After successfully configuring your driver to work with BuenaVista, the video control process is very simple – camera button on the main panel decides whether you send your picture or not. Please, note that due to sophisticated compression algorithms needed to squeeze the video stream into limited bandwidth networks, sending video is very CPU intensive. Normally, frame rate of your video stream is automatically adjusted to the available bandwidth and CPU power. However, it might happen that CPU utilization is too high, slowing down the operation of the computer. In such situations you may limit CPU load using the frame rate slider on the Video Options panel (see Figure 4). Although the scale is from zero to ten, for some Connection options you might be prevented from setting your frame rate above certain default level that is deemed safe for your computer configuration.
Note:
Windows 95 operating system has often problems with handling too heavy loads. Therefore, especially on older machines, BuenaVista may hang or freeze the operating system. If that happens, make sure to turn down the video frame rate next time you run BuenaVista.
You can access additional information about the connection with a particular participant by double-clicking on the name in the participants list on the main panel. Figure 6 illustrates all the data that are displayed.
Figure 6 Statistics Panel
In case of any problems with audio connection (e.g. bandwidth, configuration), BuenaVista is equipped in the Text Chat window accessible through Tools/Text Chat menu. Type your message in the text box at the bottom and press ‘Send’ button to pass the message to all participants. Any incoming messages will be printed on the big text panel above with the name of participant who sent it.
BuenaVista for TANGO Interactive
Figure 7: BuenaVista session in TANGO Interactive.
BuenaVista for TANGO Interactive session management is performed solely from the TANGO Interactive panel. In Fig. 7 above, TANGO Interactive session manager shows BuenaVista as one of TANGO's many collaborative applications. Clicking the BuenaVista icon and using TANGO's session management to establish conferences starts TANGO's videoconferencing session. Fig. 7 lists two independent Buenavista sessions. The highlighted session serves three participants: qwerty, gcfsgi, and ps. As the "gcfsgi" suggests, one of the participants uses SGI IRIX version of BuenaVista.
Figure 8: BuenaVista for TANGO Interactive in the sending and receiving modes, respectively.
Since TANGO Interactive takes over all session management functions, BuenaVista for TANGO main window includes neither participant list, nor direct conference management buttons. In addition, user identification fields in the General Options are not needed. Since TANGO Interactive performs also the functions of Directory Service, address of the server is eliminated. Some differences also apply to the accessing and appearance of the statistics window. Other elements of BuenaVista remain exactly the same.Why don’t I hear other conference members?
There are two major reasons for that – incorrectly configured audio card or a session status problem. You can distinguish between those two observing the speaker level indicator on the main panel. If it displays changes in the incoming stream level, the problem is caused locally probably by the audio card configuration or speaker/headphones connection. Please, refer to the audio card configuration section for details.Why does audio sound choppy or clipped?
Today’s Internet is not well equipped for distribution of the real-time multimedia streams.
Thus, such problems might be simply caused by network congestion or delays. The only thing that can be done is
minimizing the bandwidth by choosing ‘Modem 28.8’ connection on General Options panel.
You can inspect the system performance data in the "Statistics" panel. If the number of late or lost packets exceeds
5%, you have a serious network performance problem.
Another possible cause of clipped audio is too high a setting of the microphone cut-off level on the sending participant machine.
Some parts of his speech fall below this level, are classified as silence and skipped. Please, instruct this participant to lower the
threshold levels.
Last modified: Mon Mar 8 03:37:20 EST 1999