There are certain cameras that specifically advertise as having the ability to do that. Usually, it is just used for downloading the video to the computer. If you have the yellow, red, and white cables and can connect it to your TV or the like, I'm surprised it won't show using your WinTV.
i have searched the forum and couldn't find my solution. i want to use a video camera with zoom capability for a live webcast. I was hoping to use one with SD storage, but cant get the computer to see thru the camera lens using the usb connection, apparently that port is for data download only. I bought a low end mini dv camera and can use a firewire, but it is bulky. Is there a way to come out of the yellow, red, white cable of a low end flash storage compact camera like the Panasonic - SDR-S7K into my computer, i tried using my Hauppauge WinTV input into my usb, but couldnt see live video. these cameras dont have firewire output.

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