Audio refers to sound signals that travel through sound waves. It is a form of sound that can be perceived and understood by the auditory system. Audio can cover a wide range of frequencies, from bass to treble, and is usually measured in hertz. All sounds that humans can hear are called audio, which may include noise and so on.Audio Transmitters, Receivers, Transceivers

 

Audio plays an important role in everyday life. It is one of the important ways of human communication, used for language communication, music performance, radio, television, movies, telephone calls, etc. Audio is also used in a wide variety of industries, including music production, advertising, entertainment, education, healthcare, and sound design.

After the sound is recorded, whether it is speech, singing, or musical instruments, it can be processed by digital music software, or it can be made into a CD. At this time, all the sounds have not changed, because CD is originally a type of audio file. And audio is just the sound stored in the computer.Audio Sample Rate Converters

 

Ⅰ.Application field of audio

 

1. Sound Design and Creativity: Audio plays a creative role in sound design, music composition, sound art, and more. It is used in filmmaking, animation, game development, sound art exhibitions, and more.

 

2. Entertainment and Media: Audio plays an important role in the field of entertainment and media. It is used in music production, film scoring, radio, TV shows, video games, and more. Audio creates an immersive sound experience in these areas, providing the appreciation and communication of music and sound.Audio D/A Converter ICs

 

3. Healthcare: Audio has some applications in healthcare. For example, audio is used in medical diagnosis, hearing aids, music therapy, relaxation and meditation, and more. Audio can have a positive impact on mental and physical health.

 

4. Education: Audio is used in education for teaching voice recording, online courses, listening training, language learning, etc. Audio can help students and learners gain better understanding and mastery.

 

5. Advertising: It is used for advertising music, radio advertisements, voice advertisements, brand voices, etc. Audio can convey emotion and elicit empathy, increasing the appeal and impact of your ads.Audio Amplifiers

 

Ⅱ. The important role of audio in language communication

 

1. Speech recognition and speech technology: Audio is used as an input signal for speech recognition technology. The speech recognition system can convert audio into text, and realize the conversion and communication between speech and text.

 

2. Speech conveys information: Audio enables us to convey information and meaning through speech. By hearing other people's voices, we can understand the words, tone, emotion and tone of what they say.

 

3. The naturalness of voice communication: Voice communication is one of the most natural and common forms of communication for human beings. With audio, we can use the rich properties of sound such as pitch, accent, and rhythm to express what we mean.

 

4. Listening and language learning: Audio plays a key role in listening and language learning. By hearing real speech, we are able to become familiar with and learn different voices, intonations, speech rates and language idioms.

 

Ⅲ. Audio file format

 

The audio file format refers specifically to the format of files storing audio data. There are many different formats. Different audio file formats can use different compression algorithms and codecs to achieve different balances between audio quality and file size.

 

1. What needs to be clearly distinguished is that the audio file and the codec are different.

 

Codec: A codec is an algorithm or software that compresses (encodes) and decompresses (decodes) audio data. An encoder converts audio data to a more highly compressed format to reduce file size. The decoder is responsible for decoding the compressed audio data and restoring it to the original audio signal. Different codecs employ different compression algorithms and strategies, resulting in different audio quality and file sizes.Audio A/D Converter ICs

 

Audio File: An audio file is a specific file format used to store audio data. It can contain raw or compressed data of the audio. Audio files usually have a specific file extension (such as .wav, .mp3, .aac, etc.) to indicate the format of the file. Audio files are responsible for storing and organizing audio data for reading and playback on a computer or other device.

 

2. Two main types of audio file formats:

 

Lossless formats such as WAV, FLAC, APE, ALAC, WavPack(WV)

 

WAV: WAV is a lossless audio file format widely used in Windows systems. It can store various audio encodings, such as PCM (Pulse Code Modulation) and compression encoding, providing high sound quality and large file size.

 

FLAC: is a lossless audio file format that preserves the original audio quality, but has a relatively large file size. FLAC is commonly used in music storage and audio production, offering the advantage of lossless sound quality.

 

APE: is a lossless audio file format that uses a lossless compression algorithm to reduce the size of audio files while preserving the original quality of the audio.

 

ALAC: is a lossless audio file format that uses a lossless compression algorithm to reduce the size of audio files while preserving the original audio quality.

 

WavPack (WV): is a lossless audio file format that uses a lossless compression algorithm to reduce the size of audio files while preserving the original audio quality.

Lossy formats such as MP3, AAC, Ogg Vorbis, Opus

 

MP3: is a lossy audio file format that is widely used for music storage and transmission. It uses audio compression algorithms to reduce file size by removing parts of the audio signal that are imperceptible to the human ear. Although lossy compression will cause some sound quality loss, MP3 still maintains relatively high sound quality and wide compatibility.

 

AAC: is a lossy audio file format widely used in music, video and broadcasting. It provides higher audio quality and lower bit rate (file size), and has better audio compression efficiency than MP3.

 

Ogg Vorbis: is a free and open source audio file format that uses a lossy compression algorithm. It provides a balance between audio quality and file size, and is widely used in music and games.

 

Opus: is a lossy audio codec and file format designed for real-time communication and streaming applications.

 

Ⅳ. Audio processing

 

1. Basic audio processing: conversion and conversion between different sampling rates, frequencies, and channel numbers. Where transformation is simply treating it as another format, conversion is done by resampling, where interpolation algorithms can be employed as needed to compensate for distortion.

 

Add Effects: Effects commonly used in audio processing include reverb, echo, chorus, delay, and more. These effects can change the spatiality of audio, enhance timbre, add special effects, and more.Audio DSPs

 

Fade In and Fade Out: Fade in and fade out are gradual increases or decreases in audio volume to avoid abrupt audio starts or stops. This can be used to smooth out transitions in audio and reduce harsh audio effects.

 

Audio Mixing: Audio mixing is the process of combining multiple audio tracks into a single audio file. This can be used to create multi-track audio, add background music, mix audio, make audio clips, and more.

 

Clipping and cutting: Clipping and cutting is the process of splitting an audio file into smaller pieces or selectively removing pieces of audio. This can be used to remove extraneous parts, extract specific audio passages, or create custom audio compositions.

 

2. Digital processing: The core is the sampling of audio information, and various effects are achieved by processing the collected samples. This is the basic meaning of digital processing of audio media.

 

Storage and Transmission: Digitized audio can be stored in digital format on a computer hard drive, mobile device or other storage media. They can also be transmitted over the network or other transmission media for sharing and playback among different devices.

 

Quantization: Quantization is the process of mapping continuous analog audio signal amplitude values to discrete digital values. The sampled audio samples are mapped to the nearest discrete quantization level, converting continuous amplitude values to digital values.

 

Sampling: Sampling is the process of converting a continuous analog audio signal into discrete digital samples. The audio signal is time-divided into small time segments, and sampling is performed in each time segment to record the amplitude value of the audio signal.

 

Processing and Editing: In digitizing audio, various processing and editing techniques can be applied to change the characteristics of the audio, enhance its quality, or add special effects. This includes equalization, compression, noise reduction, reverb, time stretching, volume adjustments, and more.

 

Ⅴ. How audio streaming works

 

Audio streaming is a technology that transmits audio content to users in real time through the network. Here's how it works:

 

1. Dynamic bit rate adjustment: Audio streaming usually supports dynamic bit rate adjustment. According to network conditions and device performance, the client can automatically adjust the bit rate of the received audio data.

 

2. Audio encoding: Audio streaming first encodes the original audio signal. The encoding process converts audio into a digital format and compresses it into a smaller amount of data using specific audio encoding algorithms.

 

3. Real-time transmission: When a user requests to access audio content, the streaming media server will transmit the audio data to the user device through the network in the form of data packets.

 

4. Buffering and playback control: In order to avoid playback interruption or freeze, streaming media clients usually use buffers to receive and store a certain amount of audio data. The buffer allows some latency to ensure continuous audio playback.

 

5. Streaming server: Audio streaming requires a streaming server to store and transmit audio content. Streaming servers store encoded audio files and divide them into small chunks, or packets, so they can be transmitted over a network.

 

Frequently Asked Questions

 

1. What innovative audio applications are being developed?

 

In terms of audio technology, emerging new technologies and algorithms have also greatly promoted the innovation of audio applications. For example:

 

Speech recognition and natural language processing: The development of speech recognition and natural language processing technology makes speech an important way of human-computer interaction. Applications such as voice assistants, voice search, voice commands, and voice transcription are continuously improving user experience and convenience.

 

3D audio experience: 3D audio technology is designed to provide users with an immersive audio experience. By using advanced audio processing algorithms and a multi-channel speaker system, the position and movement of sound can be simulated in horizontal, vertical and depth directions, thereby creating a realistic 3D sound field effect.

 

Intelligent Audio Analysis and Classification: Audio analysis technologies are evolving to automatically classify, tag and identify audio content. This can be used in music recommendation, audio content search, copyright management and other fields.

 

Audio social media: Audio social media platforms are emerging to provide users with new ways to share and communicate audio content.

 

2. How is audio quality measured?

 

Stereo image: For stereo audio, stereo image refers to the positioning and distribution of audio in the stereo field.

 

Signal-to-Noise Ratio: The signal-to-noise ratio is a measure of the ratio between the audio signal and the background noise. A higher signal-to-noise ratio means that the audio signal is clearer and more audible relative to the noise.

 

Dynamic Range: Dynamic range refers to the difference between the maximum and minimum signal strength an audio system is capable of handling. Greater dynamic range means that the audio system can handle a wider range of signals.

 

Frequency Response: Frequency response is a measure of the audio system's ability to handle sounds of different frequencies. A good audio system should be able to accurately reproduce sound from low frequencies to high frequencies without overemphasizing or weakening specific frequency ranges.