What is the difference between digital and analog? Well, before the digital age, audio and video was stored in a format called analog and the media that contained the analogue signals includes vinyl records of various sizes (33, 45, 78), cassette tapes, and VHS tapes.
An analog recording captured the actual audio and video waves as a continuous stream of data and transferred these waves onto a physical medium – such as the groove of a record, or the iron oxide surface of a magnetic tape.
Analog recordings tended to deteriorate with time because of their dependence on the physical medium.
A digital audio or video recording does not capture the entire stream of data. Instead, it takes samples of the video and audio thousands of times a second, converts the data into a large series of numbers (1s and 0s), and then stores these numbers in a file on a computer, CD, or DVD disc.
Digital recordings do not deteriorate and, because they are numerical, they can often be compressed in order to create a smaller file size - such as with mp3 files.
Audio and video files on the computer or Internet are digital. These files are very large, especially video, so for Internet transfer, they must be compressed – or made smaller. A special program, called a codec, compresses the file without compromising quality. The word codec is short for “compress/decompress,” or possibly "code/decode."
When playing a digital audio or video file, the computer software or the playback device that is used must also use a codec program to decompress the video – to return it to its original series of 1s and 0s.
There are many audio and video codecs in use, and most media playing software and playback devices only support a subset of the total available.
Some video codecs are: MEG-1, MPEG-2 MPEG-4, Vorbis, and DiVX- based on MPEG-4.
Some audio codecs are: WAV and MP3.
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1 comment:
Such a great help. Gave me a much more detailed and adequate understanding of not only the differences between each but also the way they individually function. Thank you!
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