AHA Format Files

The "AHA Format" was defined in 1980 for storage of database records on 9-track digital tape. Signal files in AHA format are in format 16, with two signals multiplexed into one file (see section 5.3 Multiplexed Signal Files), and may be read and written using getvec and putvec. AHA-format annotation files are binary, and contain fixed-length (16-byte) annotation records. An annotation file in AHA format may be read or written using getann or putann, if the stat field of the WFDB_Anninfo object is set to WFDB_AHA_READ or WFDB_AHA_WRITE before opening the file. annopen recognizes the format of input annotation files automatically and prints a warning if the format does not match what was expected on the basis of stat. AHA format annotation files may be converted to standard format without loss of information, and doing so reduces the storage requirement by a factor of eight.

Yet another format has been used more recently for distribution of AHA DB files on floppy diskettes and CD-ROMs. This format is compatible with neither the original AHA format nor with any of the formats supported directly by the WFDB library. Programs `a2m' and `ad2m', supplied with the WFDB Software Package, can convert files in this format (as well as those in the original AHA format) to the standard formats.