Game Audio Tutorial - Book - Chapter 2 - Part1

After working through chapter one of the Game Audio Tutorials and learning some fundamental knowledge about the basics of UDK audio implementation I moved on to chapter two.

Exercise set 2:

200_00 Sample rate room

In this exercise it was highlighted that audio can be imported at different sample rates in order to reduce memory usage. The the audio samples that were already used in the exercise had to be exported and re-edited using reduced sample rates and cleaner cuts, reducing file size and sample length respectively. For this a frequency analyser (to asses what frequency content was present) and an EQ plug in (low pass filter with steep cut off to preview how the sample rate cut off would sound) were utilised along with an understanding of the Nyquist theory to determine how low the sample rate could be reduced  to save memory whilst retaining audio quality.

201a_00 Multiple use through pitch change

Here another memory saving technique was investigated by making use of a single audio file to be used for various sounds in the same room by using pitch shifting. This included using a machinery ambient sound to represent 3 different sizes of the same machine.

202_00 Multiple use through filters

This exercise was a continuation of the previous only this time as well as using only 1 sample to represent gas escaping from various pipes around the room, there also had to be an application of a low pass filter attenuation. This is where the sound is filtered over a distance using min and max radius settings, this used in conjunction with the volume attenuation over distance reflected a more realistic acoustic environment.

203_00 [AmbientSoundNonLoop] : Wooded area

This was another memory saving exercise where a ‘Non Loop’ actor was introduced. This is a sound playback device that uses multiple samples which are played back randomly in a loop. In this case the sound of birds calling from trees was triggered to simulate a more realistic an non repetitive sound-scape.

204_00 Adding a SoundCue

The 'sound cue' was introduced which is a device similar to the kismet but just for sound and can be used to playback an audio in a variety of ways. This was presented as a more effective and controlled way to play back the looping bird ambience created in the previous exercise. Sound Cues can be placed in multiple locations and edited globally as opposed to the 'Non Loop' actor where if an edit was made to one it would have to be done to all individually.