DataTurbine Audio-Video Capture and Display

rbnbAVCP

User Manual

V1.0

  December 16, 2004

Copyright, Creare Inc.

Table Of Contents

Introduction

Overview
Setup and Startup

Menu Bar

File

Capture Parameters

Operation Controls

Playback Buttons
Position Slider

Introduction

Overview

rbnbAVCP is a Java application which connects to a DataTurbine, and is capable of both capturing and displaying audio-video information.  The video is a series of JPEG images.  rbnbAVCP can either just capture audio-video information, just display audio-video information, or else simultaneously capture and display audio-video information.  rbnbAVCP lets you move back and forth between live and playback display in Tivo-like fashion.  The following figure illustrates a sample rbnbAVCP user interface window:

rbnbAVCP screenshot

Screencapture of the rbnbAVCP application.

Setup and Startup

rbnbAVCP needs to be run under a Java Virtual Machine (JVM).  It uses the Java Media Framework™ (JMF) API to capture the audio-video off an audio-video camera connected to the computer.  To register devices with JMF under the Windows operating system (so they can in turn be located by rbnbAVCP) run "jmfregistry.exe", which comes with the JMF distribution.  To run rbnbAVCP, the JMF libraries need to be in your classpath.  Alternatively, they may be located in the "lib\ext" directory under the Java JRE installation.  Use the operating system specific JMF library, rather than the generic Java version of the JMF library. The JMF library can be found at http://java.sun.com/products/java-media/jmf/.

Menu Bar

rbnbAVCP has a File pull-down menu described in the next section.

File

The File pull-down menu provides the following selections.
 
Connect...  Open a connection between rbnbAVCP and a DataTurbine.  Provide the host (name or IP address) and port number of the DataTurbine to which you would like to connect.  An example of the connection dialog is shown below.
Disconnect...
 Close the current connection between rbnbAVCP and the DataTurbine.
View...
 Specify the name of the DataTurbine source from which to request audio-video data.  An example of the dialog box is shown below.  The "Play Audio" checkbox allows the optional playing of the sound channel from the source.  In the specified DataTurbine source, the video data will come from a channel with the name "Video.jpg" and the audio data will come from a channel with the name "Audio".
Close
 Close the audio-video display.  This will not effect the current capture mode (if data is currently being captured).  This operation only effects the display of the video and audio data.
Capture...      
Capture audio and video data from a connected device and send the data to the connected DataTurbine.  You must already have established the DataTurbine connection using the "Connect..." menu item.  A dialog pops up allowing the user to configure the capture parameters.  The parameters on this dialog are discussed below.
Stop Capture
 Stop a currently active capture.
Exit Exit the rbnbAVCP program.

DataTurbine connection dialog

Connect dialog used to connect to a DataTurbine.


View dialog

View dialog used to request the display of audio-video data from a given source in the DataTurbine.

Operation Controls

The top part of the rbnbAVCP window contains a variety of operation controls.  Refer to the example rbnbAVCP screen above for reference.

Playback Buttons

When viewing audio and video data from a DataTurbine, a series of tapedeck-like controls along the top of the rbnbAVCP window allow the user to  control the data being viewed.
 
|<
 Go to beginning (oldest) of data.
<
 Play continuously backwards.
<|
 Single-step one interval backwards.
||
 Pause (stop) playback.
|>
 Single-step one interval forwards.
>
 Play continuously forwards.
>|
 Go to end (newest) of data.
realtime mode
 Real-time (continuous) update.

Position Slider

The slider bar just below the tapedeck-like position controls is an alternate way to set the data position (time).  Pull it left or right until the desired time-stamp is displayed above the video image.

Capture Parameters

The parameters used by rbnbAVCP to capture audio and video data are specified in the "Capture Options" dialog box, acessed from the "Capture..." menu item under the File menu.  A sample dialog is shown below.


Capture dialog

Capture dialog to specify parameters for capturing audio and video data.

The Output parameters specified in this dialog box are described below.

RBNB Source Name
 Desired name of the source in the connected DataTurbine where audio-video data should be stored.
Cache (frames)
 Specifies the size of the in-memory cache in terms of number of frames.
Archive (frames)    
Specifies the size of the data archive in frames.  This can be set to 0, in which case no archive will be created.

The Video parameters specified in this dialog box are described below.

Device
 Specify the device from which to capture video data.
Format
 Specify the format of the captured video image.  The selections in this list are dependent on the capabilities of the selected video device.
Resolution
 Specify the number of pixels per captured image.  The selections in this list are dependent on the capabilities of the selected video device.
Frame Rate
 Specify the number of video frames sent to the DataTurbine per second.

The Audio parameters specified in this dialog box are described below.

Capture Audio
 Specify if you would like to capture audio data along with the video data by selecting (capture audio data) or unselecting (do not capture audio data) this checkbox.
Device
 Specify the device from which to capture audio data.
Format
 Specify the format of the captured sound data.  The selections in this list are dependent on the capabilities of the selected audio device.
Sample Rate
 Specify the sample rate, in samples per second.  The selections in this list are dependent on the capabilities of the selected audio device.
Bits per Sample
 Specify the number of bits per sample.  The selections in this list are dependent on the capabilities of the selected audio device.
Mono/Stereo
 Specify if you would like to capture a mono or stero audio signal.  The selections in this list are dependent on the capabilities of the selected audio device.