Codec and streaming media can be best described as “body and soul.” Streaming media is nothing without codecs. Codecs are involved at each and every step starting from video shooting to editing and also encoding the streaming media files for delivery. Codecs are also very important during video production that touches DVD-ROM and BLU-ray markets.
If you are new to codec, then reading this article will give you a fair amount of knowledge about what codec is, where are they used and what the different types are. So, let us get going.
What is a codec?
To explain it in layman terms, codec is either a hardware device or a piece of software which is capable of encoding/decoding a signal for transmission or a digital stream over a network of data. Codec can be used for both audio and video. In other words, codecs are nothing but compression technologies, made up of two components- an encoder (to compress files) and a decoder (to decompress). The only difference between the two is that one is an algorithm design (for audio compression and decompression) and the other one is a video decoder. Codecs can be used for the following-
- Data (PKZIP)
- Still Images (JPEG, GIF, PNG)
- Audio (MP3, AAC)
- Video (Cinepak, MPEG-2, H.264, VP8)
Codecs can further be divided into two categories-
- Lossless Compression- This is a type of data compression algorithm, using which files can be compressed and decompressed without any loss of quality. Examples of Lossless codecs are- PKZIP, PNG.
- Lossy Compression- under Lossy codecs, the data algorithm discards some of the data in the file, making it easier to transmit. This category of codec is generally used when the network connection is not that good. Thus, lossy codecs can give a facsimile of the original file upon decompression, but not the original one. This type of compression uses two types of compression- intra-frame and inter-frame.
The Purpose of Codecs-
The first codec is hardware-based. It is used to perform analog to digital and vice versa conversion. One of the most common examples is the modem (router) that is used for sending data traffic across analog voice circuits.
The second type of codec is more commonly used now to describe the process of source voice encoding and video captured by a microphone or a video camera (in digital form). This is used for transmission to other people participating in calls or video conferences, etc.
As mentioned above, codecs are used for various purposes like audio, video, image, etc. Let us study them in depth below.
- Audio Codecs- Audio codecs are used to convert analog audio signals to digital and at the receiving end it converts digital audio signal to analog audio. Just like how sound cards are used in computers. The most widely used audio format is Pulse Coded Modulation (PCM).
- Video Codecs- Just like audio codecs, video codecs are used to convert analog video signals into digital ones. It can be used to encode the video in formats like MP4 and AVI, etc.
- Image Codecs- Image codecs are considered for compression when there is a need to save some space on the disk. If the image quality is low, the website downloading speed will be high. Eg JPEG, PNG, GIF.
- Data Codecs- Nobody would want to lose out important data in the process of decompression. That is the reason lossless codecs are used for this purpose. Examples of these codecs are PNG and PKZIP.
How codecs work?
The primary job of codecs is transformation and encapsulation of data for transmission across a specified network. Audio and Video codecs use software algorithm that runs on a common processor or in special hardware which is optimized for data encapsulation and decapsulation. Algorithms are used by predictive codecs to convert data into a byte sequence for ease during transmission. This is again converted back into audio or video for receiving at the endpoint.
Each stage in online video production as well as distribution involves the use of codecs. Hence, it is important to understand the basics and their operation. So if you are into video production or distribution, it is imperative for your business to have the best and top-notch products and technology.
At Mediakind all your needs are their priority. They understand the evolving nature of media and technology and hence are always there to equip you with the best.