For over a century, humans have been using analog devices (ranging from wax cylinders to magnetic tapes) to record sound waves. As with video, digital audio recordings are all the rage today. Because a digital recording can only contain specific values, it can only approximate a continuous wave of sound; a digital recording device must “sample” a sound many times per second; the more samples per second, the more closely the recording can approximate the live sound (although a digital approximation of a “wave” actually looks more like the stairs on an Aztec pyramid). The number of samples per second is called the sampling rate. As you might expect, a higher sampling rate provides better recording quality. CD audio typically has a sampling rate of 44.1 kHz — that’s 44,100 samples per second — and most digital camcorders can record at a sampling rate of 48kHz. You will work with sampling rate when you adjust the settings on your camcorder, import audio into your computer, and export movie projects when they’re done.
Understanding sampling rates
google blogger on Tuesday, July 15, 2008
For over a century, humans have been using analog devices (ranging from wax cylinders to magnetic tapes) to record sound waves. As with video, digital audio recordings are all the rage today. Because a digital recording can only contain specific values, it can only approximate a continuous wave of sound; a digital recording device must “sample” a sound many times per second; the more samples per second, the more closely the recording can approximate the live sound (although a digital approximation of a “wave” actually looks more like the stairs on an Aztec pyramid). The number of samples per second is called the sampling rate. As you might expect, a higher sampling rate provides better recording quality. CD audio typically has a sampling rate of 44.1 kHz — that’s 44,100 samples per second — and most digital camcorders can record at a sampling rate of 48kHz. You will work with sampling rate when you adjust the settings on your camcorder, import audio into your computer, and export movie projects when they’re done.