我是音频编解码器领域的初学者，很难理解；采样率、比特率和任何其他参数如何影响编码/解码[音频格式]、音频质量和文件大小。
我读到恒定比特率比可变比特率好，但是如何知道在不影响质量的情况下以尽可能小的尺寸对文件进行编码是完美的比特率。我目前特别关注音频编解码器。
我听说过 OPUS、SILK、G.722、SPEEX，但不知道应该使用哪一个来获得更好的质量和更小的文件大小。此外，我应该为此编解码器设置哪些参数，以便它们可以有效地为我工作。
有人可以指导吗？
提前致谢
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If you think of the original analog music as a sound wave then converting it to digital means approximating that wave as digital bits. The sampling rate is how many points on that wave you are taking per unit time so the higher the sampling rate the closer you are to the original sound. Lower sampling rate means higher compression but lesser audio quality.
Similarly the bit rate is effectively 'how much' information you're encoding at each point so again, lower bit rate means higher compression but lower audio quality.
Compression algorithms generally use pyschoacoustics to try to determine what information can be lost with the least amount of audible difference. In some sections of a track this may be more or less than in others so using a variable bit rate enables you to achieve higher compression without a 'big' audible drop in quality.
It's well explained here: Link
I don't know the details of those codecs but generally what you should use and what parameters you should pass depends on what you're trying to achieve and for what purpose. For portable use where audio quality might not be paramount you might want to pass lower values to achieve smaller file sizes - for audiophile speakers you probably want to pass the maximum.
于 2013-08-03T14:23:20.327 回答