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Foundation Flash CS4 for Designers- P9

Foundation Flash CS4 for Designers- P9: I can remember the day as clear as if it were just yesterday. I was walking by my boss’s office late one winter afternoon at the college where I teach, and he called me into his office. Sitting on his desk was a thin, white box with some sort of weird swirl on it. He slid the box across to me and asked, “You know anything about Flash?” | CHAPTER 5 All perceptual encoders allow you to choose how much audio is unimportant. Most encoders produce excellent quality files using no more than 16 Kbps to create voice recordings. When you create an MP3 you need to pay attention to the bandwidth. The format is fine but if the bandwidth is not optimized for its intended use your results will be unacceptable which is why applications that create MP3 files ask you to set the bandwidth along with the sample rate. So much for theory let s get practical. Adding audio to Flash Knowing that you can bring all of these formats into Flash and that MP3 is the output format for Flash is all well and good. But how do they get into Flash and more important how does an AIFF or WAV file get converted to an MP3 file when it plays in Flash Let s explore that right now starting with an import. Importing an audio file To see what happens when you import an audio file open a new Flash document and import SeeYouInTheSpringtime.aif in the Exercise folder for this chapter to the library. Due to the unique manner in which sound files are added to a Flash movie they simply cannot be imported to the stage. If you select Import to Stage when importing an audio file it won t be placed on the stage. Instead it will be placed directly into the library. When you open the library and select the file you will see the file s waveform in the preview area as shown in Figure 5-2. You can click the Play button located above the waveform in the preview area to test the sound file. Figure 5-2. Select an audio file in the library and its waveform appears in the preview area. 226 AUDIO Setting sound properties To set the sound properties for an audio file double-click the speaker icon next to the audio file s name in the library. Figure 5-3 shows the Sound Properties dialog box for SeeYouInTheSpringtime.aif. Figure 5-3. The Sound Properties dialog box is opened when you double-click an audio file in the library. This dialog box is a really useful tool.