[JAVA][Beginning Java 8 Games Development]

Chapter 15 ■ Implementing Game Audio Assets: Using the JavaFX AudioClip Class Audio Sequencing Engine
Setting the Audio Sample Frequency: Reducing Your Memory Data Footprint by
Another 200%
The proper way to set the digital audio sampling frequency for your project in Audacity is to use the drop-down
dialog for the project’s sample frequency setting. This can be seen in the lower left corner of Figure 15-6, highlighted
inside of a red box. Select the 11025 frequency setting, which reduces the audio data (think of these as vertical slices
of the sound wave) sampling rate from 44,100 times per second, to 11,025 data slices per second, or a 4X reduction in
audio data sampled in the first place, which is a 200% reduction in data footprint due to this sample frequency step in
the data (in this case, you should look at this as memory used, more than file space used) optimization work process.
Figure 15-6. Reduce audio sampling frequency by four times by reducing it from 44100 per second to 11025 per second
You can play around with these seven different settings, between the 44,100 and 8000 sample frequency rates, as
each of them will have a different quality level, with 8000 being too low of a quality to use for voice samples, but which
might work well with a “dirty” or “noisy” sound, such as an explosion.
If you want to hear what these different settings sound like, after you select each one of course, click on the
green play (right facing triangle) in the audio transport buttons shown at the top-left of Figure 15-6. You will see that
the 32,000 frequency sounds just like the 44,100 frequency rate, as does the 22,050 frequency. The 16,000 or 11,025
frequency rates do not sound as “bright” but are still usable, so I used the 11,025 rate, to get an even 4X downsample
of the data. This is because downsampling by an even 2X (100%) or 4X (200%) will always provide the best result. This
is because of the math involved leaving no “partial” samples (or pixels, since the same concept applies with imaging).
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