Adding additional Video Cameras
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What encoder are you using?
The Web Broadcaster and the free Producer software will each publish from a single camera source. To incorporate mutliple camera sources (on a single machine), we recommend the < ahref="https://www.ustream.tv/producer">Producer Pro software (US$199).
There are other solutions: incorporating an external video switcher in front of a software encoder, or a standalone hardware system such as NewTek's Tricaster.