Digital TV techniques have already entered practical stage. Applications of HighDefinition TV (HDTV) and Standard Definition TV (SDTV) will existent together fora long time.

数字电视已进入实用化阶段，不同等级的数字电视业务(如hdtv和SDTV)将长期共存。

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The 480p and 480i formats are called the SD (standard definition) formats, and 480i is roughly equivalent to a normal analog TV picture.

480i和480 p称为标清(standard definition sd)格式，480i的品质基本等同于模拟电视信号。

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The first box had a tiny hard drive (40 gigabytes to store fewer than 50 hours at standard-definition TV resolution) and an older, slower Intel chip.

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According to RootMetrics, that's a download speed of at least three megabits per second -- fast enough to download a 30-minute standard-definition TV episode in less than 10 minutes.

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The same advanced U-verse TV experience and features available today, including the ability to watch live Standard Definition or High Definition TV and access interactive TV apps, your program guide, the U-verse Movies library and more.

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