axvpb.pb.srcSelect

C Specification

#define AX_PB_SRCSEL_POLYPHASE  0x0000  // N64 type polyphase filter (4-tap)
#define AX_PB_SRCSEL_LINEAR     0x0001  // Linear interpolator
#define AX_PB_SRCSEL_NONE       0x0002  // No SRC (1:1)

u16 srcSelect;

Description

The srcSelect specifies which SRC (Sample Rate Converter) to use for the given voice:

• AX_PB_SRCSEL_POLYPHASE
  This SRC applies a four-tap polyphase FIR filter to eliminate aliasing/imaging components. While providing a very 'clean' signal, the signal has a truncated frequency band as dictated by the coefficients of the filter. You must select the coefficients using the axvpb.pb.coefSelect parameter. It is very similar to the SRC commonly used in N64 applications.
• AX_PB_SRCSEL_LINEAR
  Linear interpolation. Highly recommended for most applications.
• AX_PB_SRCSEL_NONE
  This mode will bypass the SRC stage entirely. The mode is useful for samples which do not need to be pitch-shifted (e.g., software streams with 32-kHz sample rate). You must assert the AX_SYNC_USER_SRCSELECT synchronization flag in axvpb.sync, when setting a new srcSelect type.

See Also

axvpb.sync
axvpb.pb.coefSelect
AXSetVoiceSrcType

Revision History

03/01/2006 Initial version.