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<h2 class="pHeading2">
HDTV
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HDTV 是&quot;高清晰电视&quot;(High Definition Television) 的缩写，它能够产生比标准电视更好的图像质量，而且是影院屏幕的宽屏模式。两种最常用的格式为 1080i 和 720p，这里的数字代表水平扫描的行数，数字后的字母代表图像是否使用了隔行扫描或逐行扫描技术。隔行扫描的图像先绘制奇数行然后再绘制偶数行，而逐行扫描则一次性绘制所有扫描行。这两种格式的纵横比都为 16:9。而标准北美电视信号使用的是 480 隔行扫描 (480i)，纵横比为更接近方形的 4:3。
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