Adobe 22011292 User Guide - Page 45

ADOBE AUDITION 31 User Guide The AIFF format is a good choice for PC/Macintosh cross-platform compatibility. Before you open AIFF files in Adobe Audition, add the .aif or .snd extension to the file and load it using the Apple AIFF file filter. When transferred to a Mac, you can add the four character code "AIFF" in the file's resource fork to have it recognized (The Macintosh identifies a file through its "resource", which is stripped away when a file is opened on a PC. However, many Mac applications that support AIFF can recognize the PCM data without this identifier.) ASCII Text Data (.txt) Audio data can be read to or written from files in a standard text format, with each sample separated by a carriage return, and channels separated by a tab character. An optional header can be placed before the data. If there is no header text, then the data is assumed to be 16-bit signed decimal integers. The header is formatted as KEYWORD: value with the keywords being: SAMPLES, BITSPERSAMPLE, CHANNELS, SAMPLERATE, and NORMALIZED. The values for NORMALIZED are either TRUE or FALSE. For example, SAMPLES: 1582 BITSPERSAMPLE: 16 CHANNELS: 2 SAMPLERATE: 22050 NORMALIZED: FALSE 164 -1372 492 -876 etc... Options Choose any of the following: • Include Format Header places a header before the data. • Normalized Data normalizes the data between -1.0 and 1.0. Audition Loop (.cel) Audition Loop files are essentially MP3 files with a .cel extension, but with a header that contains two important items. The first is the loop info, just as it's saved with a .wav file and is set under View > Wave Properties > Loop Info. This includes number of beats, tempo, key, and stretch method. The .cel file also works to avoid a problem with MP3 files. It's in the nature of MP3 files that a very small amount of silence is added to the beginning and/or end of an MP3 file when it's encoded. This is very short, and often only a few samples long. When working with a loop, though, it's enough to throw the entire loop off.