Best Practices for Live Streaming

Part 1. Optimizing Input

Audio and Video Sources

It is important to start with the best-quality source. This section lists possible sources:

Serial digital interface (SDI) video. Used for digital video cameras and camcorders. Because the content stays in a digital format throughout the capturing and encoding processes, this results in the least amount of data translations, and results in the best-quality video.

Component video. Used when sourcing from DVDs. With this source, the video signals are separated, for example, into the RGB or Y/R-y/B-y format. Results in good-quality video.

S-Video. Used for S-VHS, DVD, or Hi-8 camcorders. The video signal is divided into luminance and chrominance. Results in good-quality video.

DV video. Used with DV devices, such as MiniDV digital camcorders connected through an IEEE 1394 video port. Results in good-quality video.

Composite video. Used for analog cameras, camcorders, cable TV, and VCRs. Composite video should only be used as a source as a last resort. With composite video, luminance and chrominance components are mixed, which makes it difficult to get good-quality video.

Audio. If possible, capture digital audio. If you must capture audio from an analog source, balanced audio connections are better than RCA.

Optimizing Your Computer

Before you start capturing, optimize your computer using the following steps:

Defragment your hard disk.

Turn off network and file sharing.

Close all other programs, especially if a program accesses the hard disk.

Monitor system resources, making sure that the computer is sufficiently powerful to keep pace with the data feed.

Watch for direct memory access (DMA) buffer conflicts between the capture card and the SCSI card, which can result in frame dropping. This is less likely to occur now than in the past. If conflicts occur, one solution is to use a dual PCI bus motherboard configuration, in which the capture card and the SCSI card are on different buses.