The Basic Content and Process of Audio Editing Technology

- Aug 01, 2018-

Digital audio technology refers to the method of processing sound using digital technology. Digital audio can be saved on disk in sound file WAV format or MIDI format. Usually, the analog audio is analog/digital converted by a computer's sound card (also called an audio card), and the analog signal is sampled and quantized to obtain a digital audio signal.

Digital audio signals can be processed and processed by computers, such as editing, synthesizing, muting, adding reverberation, adjusting the frequency, etc., so that the sound effects can more effectively enhance the theme atmosphere, so for multimedia display systems, multimedia advertisements, video special effects In other fields, digital audio signals are even more important.

In terms of sound storage, conventional analog audio signals are recorded in analog media such as tapes or records. The disadvantage of analog media is that it is difficult to save. And the storage efficiency is very low and the cost is high. Digital audio signals can be stored in optical storage media or magnetic storage media in the form of files for permanent storage.

In terms of sound processing, the correction of analog audio signals is very complicated. In the later audio processing, digital audio technology can easily perform a variety of corrections and processing, such as changing the pitch, correcting voice errors, changing the rhythm, and even adding a large number of sound effects, greatly simplified the difficulty of audio editing work.

In terms of compression of sound, the compression ratio of analog audio is difficult to increase. Digital audio technology has an absolute advantage in data compression. For example, the most popular MP3 audio format currently has a compression ratio of about 7%, while maintaining good sound quality.

The process of converting an analog audio signal into a digital audio signal is a digitization process for an analog audio signal. The digitization process of analog audio signals requires three steps: sampling, quantization, and encoding.

Sampling is only discretized in time. The amplitude of the audio pulse signal is still analog, so the amplitude must also be discretized. This process is called quantization. The process of quantization is as follows: first divide the whole amplitude into a set of finite small amplitudes (quantization step sizes), classify the amplitude values falling within the same order into one class, and assign the same quantized value.

The sampled and quantized audio signal must also be converted to a digitally encoded pulse to be a digital signal. This conversion process is called encoding. The simplest way to encode is binary encoding. That is, the n-bit binary code is used to represent the quantized sample values, each binary number corresponds to a quantized value, and then they are arranged to obtain a digital information stream composed of binary pulses.

Audio digitization is the digitization of analog sound waveforms for processing with a digital computer. The technical indicators that affect the quality of digital audio signals mainly include sampling frequency, sampling accuracy, channel number and encoding algorithm.



MAONO is an innovative designer and manufacturer of Lavalier, Podcasting, Wireless, Shotgun, Recording microphones and accessories for Smartphone, Camera and PC, etc.