[JAVA][Beginning Java 8 Games Development]

Chapter 15 ■ Implementing Game Audio Assets: Using the JavaFX AudioClip Class Audio Sequencing Engine
The next thing that we will do is to go back and use the File ➤ Open menu sequence to open the left.wav file that
contains only the segment of digital audio data that we wish to optimize. This is seen in the middle of Figure 15-3
(the menu sequence), and on the right side of the screenshot you can see a Select one or more audio files (File Open)
dialog. Notice that the left.wav file shows what its raw (original) data footprint is (113 KB).
We can use this original data footprint as a baseline to see how many times we reduce the data footprint (it will
eventually be 8.8 times smaller, once we are done) during this optimization process we are about to embark on.
When you click on the Open button and open a file for the first time in Audacity you’ll get a Warning dialog, which
is shown in Figure 15-4. This will advise you that you can make a copy of your original file for use in your editing session,
instead of using the original. This is what is called “non-destructive” editing in the multimedia industry, and is always a
very good idea, since it essentially provides you with a back-up file (the original), as part of the work process.
Figure 15-4. Enable non-destructive audio editing in Audacity
Select the “Make a copy of the files before editing (safer)” radio button option, and check the “Don’t warn again,
and always use my choice above” checkbox, which will turn Audacity 2 into a non-destructive non-linear digital audio
editing software package. Click on the OK button and we’ll be ready to start your digital audio data optimization work
process. We will be optimizing our digital audio data, but not compressing it, and I will get into why that is next.
Optimization Versus Compression: The Audio Memory Footprint
You might be wondering why I am using the uncompressed, pulse code modulated (PCM) Wave (.wav) file format
instead of the industry standard .MP3 file format that many of you use for your digital audio music file storage. I will
cover the reason for this up front, before we start the optimization process. In digital audio, there are really two stages
to data footprint optimization. First you optimize the sample resolution (32-bit original recording, 24-bit HD audio,
16-bit CD Quality audio and 8-bit lower quality audio) and the sample frequency (44.1kHz, 22.05kHz, 11.025kHz are
the primary frequency levels that still maintain enough data for a quality result), and then you apply the compression.
The compression affects your file size; in this case it is your .JAR (Java Resources) file.
So, why are we not compressing our files into MP3 format, to make our .JAR file a few kilobytes smaller? A primary
reason for this is because MP3 is a “lossy” format, which throws away original data (and quality) for the audio sample.
Since the JavaFX AudioClip class is going to take our digital audio assets and decompress them into memory, if we
use MP3, that memory will contain lower quality audio data that if we use WAV format. Given that we are going to
get at least an 8X data footprint reduction during the sample optimization work process that we are about to learn
in the next section of the chapter, and that all our digital audio assets are going to be optimized to between 4KB and
14K of data footprint, MP3 compression is not going to give us any real JAR file data footprint reduction relative to the
reduction in sample quality that it will “cost” us. Game audio is short-burst sound effects and musical loops, so we can
use WAV file format and still get a good result, and not have to use any compression. The other advantage is the data
size of the WAV file that you see in our file management software is also the amount of memory the sample will use.
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