The History Of Digital Media

Published Date: 02 Nov 2017

The two file formats that I chose were: WAV (.wav) for a professional broadcast quality and MP3 (.mp3) for an internet/podcast quality.

WAV file format, also known as ‘Waveform’ was created by Microsoft and IBM in 1991. It was created to be used on the Microsoft 3.1 Operating System. The WAV file format is based on Resource Interchange File Format (RIFF), which is a container format for storing data in tagged chunks. Resource Interchange File Format was based on EA’s (Electronic Arts) Interchange File Format (IFF) introduced in 1985, which was used in gaming. Apple also released their own version in 1988 called Audio Interchange File Format, used for Macintosh computers, though, these audio files will play on any operating system.

WAV file format is a Lossless Compression format, which means, when the compressed audio file is converted to a lossless audio file it reconstructs the data without losing any ‘information’ from the compressed data. Most professional uses and audio experts will use the file format, WAV, because of its excellent audio quality. The reason WAV has such a great audio quality is because of its Linear Pulse –Code Modulation (LPCM) format, a way of encoding audio information digitally. This format is coded using a various set of parameters, such as: Audio bit depth, sampling rate and number of channels (e.g stereo or mono).

WAV file formats can be edited using a range of different software, which makes it easy and accessible for people who don’t wish to spend lots of money on extremely good software, e.g. Audacity (which is free!). The WAV file format is also easy to convert to other file formats and can run on both Apple and Windows operating systems. WAV file formats are uncommon to be used as file sharing over the internet, as the file sizes are very big, as a one minute in length audio track could be 35MB. WAV is a costly format in this case because of the room it can take up on a hard drive or an external hard drive. High Resolution Audio is the best quality audio that you can listen to. High resolution audio is considered to begin from 16 bit/48khz. Sampling rate is where the number of samples per second is taken from a continuous signal to a discrete signal. Whereas bit depth is the number of bits of information is recorded for each sample. In this case my high quality professional broadcast has a bit depth of 16 and a sampling rate of 48 kHz.

MPEG – 1 or MPEG – 2 Audio Layer III is more commonly referred to as MP3 (.mp3) and is a lossy compression format as it is only a fraction of a WAV file and takes up a lot less space on a hard drive. The MP3 file format was created by Moving Pictures Experts Group (MPEG) in 1995. MP3 was created so that it would take up less space and so that it would be easier to file share and store on a portable device, such as an MP3 player or a mobile phone. In fact nearly all portable devices and computers all support the file format .mp3 as it is commonly used to store and playback music. Since MP3 file format is a lossy compression format, it reduces the file from a lossless file format such as WAV to 1/11 of the file. This reduces the CD quality WAV file (16 bit/48Khz) to 128kbit/48Khz, which is a significant difference between WAV and MP3, but still retains a respectable CD quality.

The MP3 file format uses an algorithm called perceptual noise shaping, and is finely tuned to the characteristics of a human ear. These characteristics are:

When running two tracks simultaneously, the human ear hears the louder track

There are sounds that the human ear cannot hear

There are sounds that the human ear can hear better than other ears.

MP3 bit rates range from 96 to 320kpbs, with 96 being a low quality track and 320 being a high quality for an MP3 track but a low to medium quality track in comparison to a Waveform track. However, there are many advantages for the MP3 files, such as:

Can easily be distributed over the internet

Download from a website is fast and easy

Can rip a file from a CD and easily use software and convert the file to an MP3 codec

Record music yourself and convert it to MP3 then distribute on the internet

Store thousands of files on your hard drive.

With all these advantages come some disadvantages, which is mainly the reduced sound quality. Other disadvantages for a MP3 file is the fact that it is commonly distributed throughout the internet and you can download it easily; they could include a surprise package for you such as a virus, Trojan or malware, so you have to be careful with trusted download sites. Another disadvantage is that it is bad for looping as an MP3 file can include an unspecified amount of silence at the beginning and the end of a music track, which can cause this to have a burp or hiccup in the music track. MP3 files can be used for a range of reasons, such as: a background track on a presentation, a voice recording for a video, a simple remix that you made last night and want to distribute it to the world and listens to music stored on your mobile phone, on your way home. The reason I chose for my internet/podcast quality version to be stored as an MP3 file is because it is easy to encode, it is a small file size and has the option to be ‘near – CD quality’ if stored at 320kpbs and is more widely used to distribute over the internet or to friends. I chose my MP3 file to operate at 320kpbs/48Khz for the best quality possible as an internet/podcast track.