Реферат: Mp3 Essay Research Paper INTRODUCTIONTwo years ago

Mp3 Essay, Research Paper

INTRODUCTION

Two years ago, MP3 was just another audio compression format. Today, it’s a Net phenomenon that’s at the center of an enormous controversy. That’s because MP3 makes it possible for people with an Internet connection to bypass record stores (and cashiers) and download CD-quality music by their favorite artists–for free. MP3 is great for

music lovers and cheapskates, who can download funky tunes to their hearts’ content without spending a dime; however, it’s a nightmare for musicians and record companies, who can only watch helplessly as their profits drop into a digital black hole.

DEFINITION

MP3 is short for MPEG-1 Layer 3 (Moving Pictures Expert Group), a format for storing digital audio. It uses an advanced type of audio compression which reduces the filesize with little reduction in quality. MP3 is used particularly for music distribution over the Internet, but is also use for other purposes such as real-time digital audio transmissions over ISDN (used by reporters). MPEG-1 has been around since 1992, but during he last few years (1998/99) it has started to get widespread attention from regular media and ordinary users.

An MP3 file (or simply “an MP3″) is a file that contains MP3-compressed sound data. It is played using an MP3 player. You can recognize MP3 files by their file-extension (the end of the filename), which is “.mp3″.

AUTHORS

MP3 was invented by Fraunhofer IIS? leading organization of applied research in Germany In a joint cooperation with the University of Erlangen (Prof. Dieter Seitzer) under the sponsorship of the Motion Picture Experts Group (MPEG) and formalized by the International Organization for Standardization (ISO).

SOUND QUALITY

The original 50 MB wave file (about 5 minutes of CD quality audio)

MP3-compressed will end up as an MP3 file using only about 5 megabytes of space with little or no audible loss in quality. The size depends on the length of the song and the bitrate (quality). The data is automatically decompressed while the MP3 is being played.

How is it possible to do this you ask? Well, I won’t get into the technical details, but basically the MP3 encoder removes the parts of the sound not audible to the human ear. This means that MP3 is a ‘lossy’ type of compression (comparable to JPEG in the

graphics area). This means that what comes out from your CD or Wave file is NOT the same thing that comes out of the MP3 that has been created from the CD/Wav. The sound data that has been lost will not be returned if the MP3 is decoded back to WAV. REQUIREMENTS

You will first of all need a MP3 player, players are available for all computer platforms. If you are using Windows 95/98/NT we can warmly recommend Winamp, the most common MP3 player. It also supports a lot of other audio formats,like WAV, MID, MOD and CD audio. Another well-known player is Sonique. Winamp has a very simple interface that can be used by anybody who has operated a CD player. To load an MP3 in Winamp, use the button (in Winamp) that looks like it would open a CD tray, or just double-click the MP3 file you want to play. The reason why it has been so successful is undoubtedly due to its simple, attractive look, its numerous options and the fact that it is a shareware program with no limits on the number of functions

To play the MP3s will need a soundcard (preferably16-bit), speakers or headphones (preferrably good ones) and at least a 486 processor.

MP3 ON THE WEB

Three major MP3 sites are Lycos MP3 Search Engine, MP3.com, and RioPort.com.

MP3 HARDWARE

MP3 Portables

Realizing the success of MP3, thanks to the rapid growth of the Internet and the increasing numbers of users interested in this digital-audio format, a number of manufacturers have recently started marketing portable players (similar to the Walkman): they generally have a memory of between 40 and 80 MB where you can store your favourite MP3 files.

Portable MP3 players are like Walkmen for MP3. You just need to upload your MP3 tracks onto the player (about the size of a pack of cigarettes) and you get CD-quality sound with the advantage that there are no moving parts so it’s unaffected by jolts.

MP3 SOFTWARE

There are various types of software for MP3: player, decoder, encoder, ripper, grabber, utility.

Mp3 Player

Mp3 Player software (often simply called a “Player”) is a program that can read audio/video files and play them back.Usually the player offers additional characteristics such as the possibility to equalize the signal that comes out of your loudspeakers, PlayList management (sequencing files to play in a certain order or in random or shuffle mode), the possibility to convert files into different audio formats (for instance from MP3 to Wav and vice versa).

MP3 Encoder Software

MP3 encoder software (often just called an “encoder”) is a programme that can convert wave files into MP3 format. This conversion greatly reduces the size of files whilst maintaining a high standard of audio quality (this is possible thanks to compression algorithms). It is also possible to specify the characteristics of the MP3 files that you are creating, choosing from several options that will determine the final size of the file.

The reduced size of MP3 files greatly facilitates their distribution on the net, which would have been impossible in wave format, at least for the common user.

Converting Software

This type of software is a program that allows the conversion of files into different formats. Usually these programmes are not limited to converting into MP3, but support many other audio/video formats.

CD Mastering Software

It is CD writing software programme that allows you to transfer files from hard disk (or other source) onto CD in a permanent way (although today we have re-writable CDs).

To achieve this, you need a CD writer that has the same characteristics as a normal CD player, which is today a standard feature in a computer, and that can also write data onto recordable supports (the capacity is 650MB for 74 minutes, but there are CDs on the market whose capacity is 700MB for 80 minutes).

CD writing formats are standardized, but there are several versions depending largely on the software used for writing.

CD Extracting Software

CD extracting software (normally called a “grabber” or “ripper”) is a programme that can extract tracks from an audio CD, making a copy of them on hard disk in wave format. These wave files are the starting point for creating Mp3 files, which are much smaller in size; in fact many rippers feature an MP3 converter and can obtain an MP3 file from an audio CD, going through the wave format which is then automatically deleted in order to free up space.

Utility Programmes

This is software that carries out accessory operations, with no direct effect, but with the result of simplifying other operations.

Typical examples are: WinZIP (to manage compressed archives), Cool Edit Pro (to manage wave files whilst changing their characteristics or applying sound effects) and Mp3Wolf (useful in the search for MP3 files on the net).

CONCLUSION

As you can see it is Mp3 format can be very useful for end users. It is allow you to store many files of your favorite music on your hard disk and listen them any time you like using many good features of MP3 player.

BIBLIOGRAPHY:

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