I found something for the developers of SCIRRA and the webcam obj.
Because the problem i have descrived here in this forum its the same in this new example i found on the web.
If you attempt to capture live video sequences with the VidCap utility included with Microsoft Video for Windows using the Creative Labs Video Blaster capture board, you may capture a series of black frames. This problem occurs if any of the following three scenarios exist:
The computer has more than 15 MB of RAM.
The driver setting for the base memory address is incorrect.
The Video Blaster capture card is not installed properly.
For me i have the ACER crystale eye HD webcam, all updated and working fine under my windows7.
so i found this after:
When you run the VidCap utility, you may find that if you choose Overlay Video from the Options menu, the picture displays correctly; however, when you choose the Preview Video command, the picture displays as blackness or is fuzzy.
AND THIS IS WHAT THE WEBCAM OBJ IS DOING, THE PREVIEW MODE, and THAT give me black screens... SO its in your CODE.
here its this article, that speak about this kind of problem with another card BUT the same problem i have.