Notes on Segment Labels and Segment Tables

The native ASEL waveform file format supports at most 48 segment labels per file. The labels are defined in a segment table structure stored in the waveform file header. Functions written to read and write segment tables for ASEL format files are passed a 48-element table and fill in or copy out segments from the table. These functions are wavgst and wavpst respectively.

The ASEL extension to RIFF stores segment label information in special data chuncks and does not constrain the number of segments defined per waveform file. For backward compatability, the fixed-length segment table functions wavgst and wavpst can be called to return information from RIFF files and will return or store at most 48 segments. Two additional functions wavgest and wavpest have been provided to allow extended segment tables (of arbitrary length) to be read and written to RIFF files. The extended segment table functions will, of course, also work with native ASEL format files, however, wavpest will be unable to store more than 48 segment definitions.