AF_power_uf(3) AF_power_uf(3) NAME AF_power_uf, AF_power_af - ULAW and ALAW power tables SYNTAX #include <AF/AFUtils.h> extern float AF_power_uf[]; extern float AF_power_af[]; DESCRIPTION AF_power_uf and AF_power_af are precomputed tables you can link with your application. They are indexed by a ULAW or ALAW sample respectively. The tables contain, effectively, the square of the linearized sample value, scaled to the range from 0.0 to 1.0. These tables are useful for comput- ing the power in a block of ULAW or ALAW compressed samples. This is important for figuring out if the signal is silent or not, for example. EXAMPLES Typical usage is: unsigned char ulaw; float power; power = AF_power_uf[ ulaw ]; DIAGNOSTICS If you index the table with an out-of-range linear value you may cause a protection fault and crash your application. SEE ALSO AF(1) BUGS If you encounter a reproducible bug, please submit a problem report to (af-bugs@crl.dec.com). COPYRIGHT Copyright 1990-1994, Digital Equipment Corporation. See AF(1) for a full statement of rights and permissions. AUTHORS Tom Levergood and Larry Stewart, Digital Cambridge Research Lab