What is Codec (Coder-Decoder)?

A codec describes a feature developed in software, hardware, or a mixture of both, that can convert a file with a data stream or signal stream.

What are Audio, Video, Image, and Data Codec?

Codecs allow for encoding the stream or signal, and the same for playback or manipulation in a format more suitable for these operations.

Codecs are used in situations such as video conferencing and broadcasting media. Many components can cause information loss to achieve the smallest possible size of the target file.

There are also lossless codecs, but in practical application it may not provide an increase in quality and an increase in data size.

The future processing of data, repeated lossy coding can do much damage to quality in the long run.

Many multimedia files contain both audio and video data, and often there are some references that allow synchronization of both files.

Each of these three data streams can be managed with different programs, processes or hardware. However, these streams must be encapsulated together in order to be useful for storing or transmitting.

This encapsulation is done in a video file format such as .mpg, .mp4. While some of these formats contain a small set of codecs, others are used for more general purposes.

The most common types of codec formats are audio codecs and video codecs.

Formats/Types

Codec formats have many different components that offer advantages and disadvantages among themselves. Codecs are divided into four: audio, video, image, and data.

   1. Audio

1. AAC (Advanced Audio Coding)
2. ALAC (Apple Lossless Audio-Codec)
3. AMR (Adaptive Multi-Rate)
4. FLAC (Free Lossless Audio-Codec)
5. G.711
6. G.722
7. MP3 (Moving Picture Experts Group Layer-3 Audio)
8. Opus
9. Vorbis
10. AIFF (Audio Interchange File Format)
11. DSD (Direct Stream Digital)
12. WMA (Windows Media Audio)
13. WAV (Waveform Audio Format)

   2. Video

1. MPEG-1
2. MPEG-2
3. MPEG-3
4. MPEG-4
5. H.264
6. HEVC/H.265
7. AVI (Audio Video Interleave)
8. DivX
9. MOV (Quicktime)
10. FLV (Flash)
11. WMV (Windows Media)

   3. Image

1. JPEG
2. PNG
3. GIF

   4. Data

1. PKZIP
2. PNG

Audio Codecs

An audio codec is a component that contains a set of algorithms that allow audio data to be encoded and decoded. This means that the number of bits occupied by the audio file is reduced.

These codecs are used to compress signals or audio files with a data stream to achieve good quality and reproduce or process them in a more suitable format.

Compression is applied using software or hardware. There is currently a wide variety of audio codecs.

Although audio codecs are more complex and have additional features, perceptual encoders are divided into four groups as auditory threshold, temporal and frequency masking depending on the method of encoding or reducing the bitrate.

Video Codecs

Video codec is a type of codec that enables you to compress and decompress digital video. Compression algorithms normally used can cause information loss.

The biggest problem with codecs is that they take up too much space on a typical storage media such as a hard disk, CD or DVD.

This is why it was preferred to create and use these compression algorithms in real time. The goal of these algorithms is to achieve significantly less video size.

In this case, information is compressed when saved to a file and decompressed in real time during viewing.

There is a difficult balance in video quality between the amount of data, the complexity of encoding and decoding algorithms, robustness against data loss and errors, ease of editing, the ability to directly access frames, and other factors.

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