Intel® Integrated Performance Primitives (Intel® IPP) Developer Guide and Reference

ID 790148
Date 3/22/2024
Public
Document Table of Contents

WTFwdSetDlyLine, WTFwdGetDlyLine

Sets and gets the delay lines of the forward wavelet transform.

Syntax

IppStatus ippsWTFwdSetDlyLine_32f(IppsWTFwdState_32f* pState, const Ipp32f* pDlyLow, const Ipp32f* pDlyHigh);

IppStatus ippsWTFwdSetDlyLine_8u32f(IppsWTFwdState_8u32f* pState, const Ipp32f* pDlyLow, const Ipp32f* pDlyHigh);

IppStatus ippsWTFwdSetDlyLine_16s32f(IppsWTFwdState_16s32f* pState, const Ipp32f* pDlyLow, const Ipp32f* pDlyHigh);

IppStatus ippsWTFwdSetDlyLine_16u32f(IppsWTFwdState_16u32f* pState, const Ipp32f* pDlyLow, const Ipp32f* pDlyHigh);

IppStatus ippsWTFwdGetDlyLine_32f(IppsWTFwdState_32f* pState, Ipp32f* pDlyLow, Ipp32f* pDlyHigh);

IppStatus ippsWTFwdGetDlyLine_8u32f(IppsWTFwdState_8u32f* pState, Ipp32f* pDlyLow, Ipp32f* pDlyHigh);

IppStatus ippsWTFwdGetDlyLine_16s32f(IppsWTFwdState_16s32f* pState, Ipp32f* pDlyLow, Ipp32f* pDlyHigh);

IppStatus ippsWTFwdGetDlyLine_16u32f(IppsWTFwdState_16u32f* pState, Ipp32f* pDlyLow, Ipp32f* pDlyHigh);

Include Files

ipps.h

Domain Dependencies

Headers: ippcore.h, ippvm.h

Libraries: ippcore.lib, ippvm.lib

Parameters

pState

Pointer to the state structure.

pDlyLow

Pointer to the vector which holds the delay lines for “low frequency” components.

pDlyHigh

Pointer to the vector which holds the delay lines for “high frequency” components.

Description

These functions copy the delay line values from pDlyHigh and pDlyLow, and stores them into the state structure pState.

ippsWTFwdSetDlyLine. This function sets the delay line values of the forward WT state.

ippsWTFwdGetDlyLine. This function gets the delay line values of the forward WT state.

Application Notes

These functions are designed to shape the signal prehistory, save and reconstruct delay lines. Delay lines are implemented separately for highpass and lowpass filters, which gives the option of getting independent signal prehistories for each filter.

Delay line data format. Despite that any delay line formats could be used inside transformations, the functions provide the simplest format of received and returned vectors. Data either transferred to or returned from the delay lines have the same format as the initial signal fed into the forward transform functions, i.e., delay line vectors must be made up of a succession of the signal prehistory counts in the same time frame as the initial signal.

Delay line lengths. The length of the vectors that are transferred to or received by the delay line installation or reading functions is uniquely defined by the filter length and the value of additional filter delay.

The following expression defines the length of the delay line vector of the “low frequency” component filter:

dlyLowLen = lenLow + offsLow - 1,

where lenLow and offsLow are respectively the length and additional delay of the “low frequency” component filter.

The following expression defines the length of the delay line vector of the “high frequency” component filter: dlyHighLen = lenHigh + offsHigh - 1,

where lenHigh and offsHigh are respectively the length and additional delay of the “high frequency” component filter.

The lenLow, offsLow, lenHigh, and offsHigh parameters are specified by the function ippsWTFwdInit.

Return Values

ippStsNoErr

Indicates no error.

ippStsNullPtrErr

Indicates an error when pDlyLow or pDlyHigh is NULL.

ippStsStateMatchErr

Indicates an error when the state identifier pState is incorrect.