Sound for Computer Games - Exercise 3

Research and why you would use and where/when



Uncompressed sound files:



.WAV - Waveform Audio files are the most frequently used uncompressed audio file format for Windows operating systems. WAV files can be opened with Windows Media Player, and most other media player applications.



.AIFF - Audio Interchange Files are the most commonly used uncompressed audio file format for the Apple Macintosh operating system. Due to .AIF files being uncompressed, they use more disc space; around 10MB per 1 minute of stereo sound. As well as storing audio data, this file format can also store loop point data, therefore feature loops,



.AU - Audio File are simple audio files, and were used in some of the early web pages. Audacity creates and saves files in .AU file format. The format is compatible across Windows, Mac and Linux operating systems. .AU files can be opened in many media player applications, including VLC Media Player.



.SMP - SmartMusic Performance files are used by SmartMusic application for band. orchestra and voice audio sounds. This file format is compatible on Windows, Mac, Linux, Android, iOS and more.




Compressed sound files:


.MP3 - MPEG-1 or MPEG-2 Audio Layer-3 is the most frequently used digital audio file, which uses a form of lossy data compression. Used in streaming and storing of digital audio files, for transfer or playback with digital audio players. Compressed files are around one-twentieth of the original file size. MP3s are the format of choice for portable music players, such as Apple iPods, and MP3 players, but can also be used on Windows, Mac and Linux operating systems.



.RA - RealAudio files have been used in the past to stream music on radio stations, but as time passed, it's usage declined, giving way to more popular digital audio formats. developed to be a streaming format, the file can be played whilst it is downloading, and be played back in HTTP web pages. Compatible with Windows, Mac, Linux, iOS and android operating systems.



.VOX - Voxware files are . Vox files can be opened and edited using VoxWare MetaSound.





Audio Sampling

How can resolution and bit-depth constrain file size?


The higher the bit-depth of a sound is the higher the quality of the sound.

For the best quality sound available, 32-bit sound is what recording studios use. This means you need to spend a lot of time editing and manipulating the sound before you can export it. 32-bit sounds are going to be very large files, because there is a lot of data.

16-bit is the most used quality of sound, which is used in audio CDs. The file sizes are half the size of 32-bit sound files..

8-bit-depth is used for AM radio station, and tape recorders. The file sizes are usually very small, and is only used when the data storage is limited. Sound quality is low, resulting is white static background noise.





Explain what the following words mean:

• Sample Rate - The number of 'samples' of audio carried every second, measured in hertz (Hz / KHz)
• Mono - Single audio channel, usually one microphone or one loud speaker. The sound will play from one speaker/headphone, as the below diagram shows.
• Stereo - Dual audio channel, which has two loud speakers, and sound is played from two speakers/headphones.
  
• Surround - Sound from 5 or 7 speakers, placed around the room to give an immersive sound experience. Sounds will play through certain speakers, depending on where on screen the sound is coming from. For example, a plane taking off. The plane starts of the left of the screen, so sound will play from the left. As the plane moves across the screen, the sound will move with it, playing from the center speakers, followed by the right as the plane leaves the screen.