View Full Version : Problem with prepareLive

June 28, 2006, 18:34:06
I am trying to set up a switched input from a single framegrabber using the example in the prepareLive documentation in the reference. The first call to prepareLive gives me the error:

grabber1.prepareLive failed: An unexpected DShowLibException occured: Error = startLive failed.
VideoCaptureDevice = Video to 1394 Converter
VideoFormat = UYVY (640x480)
In file : "c:\csource\ic30\core\tisudshl\grabberpimpl.cpp" at line : 576

The code I use to set up my grabber is:

if( !m_cGrabber1.openDev( "Video to 1394 Converter" ) )
MessageBox( "Could not open Video to 1394 Converter" );

if( !m_cGrabber1.setVideoFormat( "RGB24 (640x480)" ) )
MessageBox( "Could not set video format to RGB24 (640x480)" );

if( !m_cGrabber1.setFPS( 15.0 ) )
MessageBox( "Could not set FPS to 15.0" );

if( !m_cGrabber1.setInputChannel( "02 Video: SVideo" ) )
MessageBox( "Could not set input channel to 2" );

I use identical code to set up the second grabber except I am reading from the Composite channel.

Why am I getting this error message? And is there anything I can do to fix it?

-Charles Bancroft

June 28, 2006, 18:37:01
As a side note, I am using the IC Imaging Control 3.0 SDK

Stefan Geissler
June 29, 2006, 09:03:20
Hi Charles,

I think it is a bandwidth problem. RGB24 has 3 byte per pixel. Use UYVY instead, it has only 2 byte per pixel. You will not find differences in the image quality, may be the UYVY has a little bit more quality.
Changing the frame rate does not reduce the bandwidth amount on the firewire bus.