A Specification for Storing Floating Point Audio Data

This appendix explains how you can store floating point audio data (IEEE float and double representation) in a QuickTime file.

The word "sample" is used here to describe a single measurement of one channel of an audio signal at a single time. Hence, a sample is represented by one number. Don't confuse this with the QuickTime "sound sample description" chunk, which describes the format of a collection of audio samples.

The terms "A/D device" and "D/A device" refer to a complete system (i.e., analog circuitry, codec, DMA hardware, kernel software, and library software) for translating between voltage levels at an analog audio jack and numerical values inside the computer (usually stored in memory). An A/D device has an analog input and a D/A device has an analog output. The concepts discussed in this section apply equally as well to other examples, such as digital audio I/O devices.

A Specification for Storing Floating Point Audio Data

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