What does audio mean?

All sounds that humans can hear are called audio, which may include noise and so on.

After sound recording, no matter the voice, aria and musical instruments, they can be processed by digital music software or made into CDs. At this time, all the sounds have not changed, because the CD was originally an audio file. And audio is just the sound stored in the computer.

If we have a computer and a corresponding sound card, that is, the sound card we often say, we can record all the sounds, and the acoustic characteristics of the sound, such as the sound level, can be stored in the form of computer hard disk files.

Basic audio processing includes the following:

Conversion between different sampling rates, frequencies and number of channels. Among them, the transformation simply regards it as another format, and the transformation is carried out by resampling, and interpolation algorithm can be used to compensate the distortion as needed.

Various transformations of audio data itself, such as fade-in, fade-out, volume adjustment, etc.

Converted by digital filtering algorithm (such as Qualcomm and low-pass filter).