TOPIC
Raw NTSC video contains 28 MB of data per second. The International standards body called Moving Pictures Expert Group has defined two compression standards for compressing video down to a more efficient and manageable size. They are defined below.
DISCUSSION MPEG-1: was defined to facilitate streaming VHS-quality video and CD-quality audio off a 1X (150K/sec) speed CD-ROM. The resolution is 352x240 at 30fps, and most Pentium class and PowerPC class computers can decode MPEG-1 streams in real time with software. An MPEG-1 software decoder is available from various sources. Apple Macintosh computers can use the QuickTime MPEG extension for this purpose. MPEG-2: was intended for high-bandwidth data streams and it's the technology behind DSS satellites and DVD video discs. Resolution is variable, but is generally 720x480, and the data rate ranges from 500K/sec to more than 2MB/sec. MPEG-4: is a standard still in the works that will define compression for ultra-low bandwidth video applications such as video conferencing over phone lines or the Internet. |
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| Product Area: | Apple General Information |
| Category: | Product Information |
| Sub Category: | General Topics |
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