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SIGNAL/RTS APPLICATION NOTES

8 Application Note 5

Exchanging Sound Files with External Systems

Binary sound files can be exchanged between SIGNAL and other data acquisition systems.

This requires that the sound files be in a format compatible with both systems. Approaches

include: (1) write SIGNAL files in headerless binary format, (2) write SIGNAL files in Wave

or AIFF format, (3) convert files from the SIGNAL format to the other system's format using

a file converter, and (4) convert the other system's files to the SIGNAL format using a file

converter. See the file import/export sections of the SIGNAL and RTS user guides for more

detail. SIGNAL can read and write headerless binary files, and the RTS can write but not

read headerless binary files. When writing a program to convert an external data file to the

SIGNAL file format, keep the following points in mind.

1. Place the label "EXT" in PGM_STAMP and leave PGM_VERSION blank.

2. Determine CNVFAC and OFFSET for the external data, either empirically, or based

on the known resolution and range of the external A/D converter.

3. Block and record marks may not appear anywhere in the file.

Programming Access to SIGNAL Files

The data section in the SIGNAL sound file is written as continuous numerical data, with no

intervening record or block marks. Data can be read and written using any of the following

software tools.

Software

Environment Routines/Settings

FORTRAN direct I/O ACCESS=DIRECT, FORM=UNFORMATTED

C low-level I/O open( ), read( ), write( )

DOS file services Open file, read file, write file =

DOS int 21h, functions 3ch, 3dh, 3eh, 3fh, 40h, and 42h

4-30-92

Rev 9-25-95

Rev 5-9-99

Rev 5-25-02

Rev 1-15-04

Rev 3-31-08 Caption extended from 72 to 80 characters

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