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使用VCD机时经常碰到停顿的现象,令人不知所措,其实原因不外乎以下几方面。 一、现在市场上的VCD机多数是厂家在原有CD唱机上加装MPEG解压缩卡改装而成,所用机芯并不是VCD机专用的。VCD专用机芯对光头的跟踪寻迹能力非常高,而普通CD机芯的跟踪寻迹能力达不到VCD专用机芯的水平,所以在播放中容易出现误码。播放普通CD唱片时,由于音频信号没有经过压缩,播放中即使出现个别误码,人们的听觉也感觉不到。而VCD盘上的数据经过50～200倍的压缩,播放中如出现误码,经过解压缩后就会出现几百个错误数据,使图象出现停顿,声音出现失真。
The use of VCD machines often encounter pause phenomenon, it is overwhelming, in fact, nothing more than the following aspects. First, most of the VCD machines on the market now manufacturers in the original CD player installed MPEG decompression card modified made of the movement is not VCD machine-specific. VCD dedicated movement tracking of the optical head tracing ability is very high, and ordinary CD tracking tracing ability to reach the level of VCD-specific movement, so prone to error during playback. Play ordinary CD record, because the audio signal is not compressed, even if there is a single error during playback, people’s hearing can not feel. The VCD disc data after 50 to 200 times the compression, such as playing error code, after decompression will appear hundreds of error data, the image appears to pause, the sound distortion.