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#include "ref.h"
void ref_fir_decimate_f32(
const arm_fir_decimate_instance_f32 * S,
float32_t * pSrc,
float32_t * pDst,
uint32_t blockSize)
{
float32_t *pState = S->pState; /* State pointer */
float32_t *pCoeffs = S->pCoeffs; /* Coefficient pointer */
float32_t *pStateCurnt; /* Points to the current sample of the state */
float32_t sum0; /* Accumulator */
float32_t x0, c0; /* Temporary variables to hold state and coefficient values */
uint32_t numTaps = S->numTaps; /* Number of filter coefficients in the filter */
uint32_t i, blkCnt; /* Loop counters */
/* S->pState buffer contains previous frame (numTaps - 1) samples */
/* pStateCurnt points to the location where the new input data should be written */
pStateCurnt = S->pState + numTaps - 1U;
/* Total number of output samples to be computed */
blkCnt = blockSize / S->M;
while (blkCnt > 0U)
{
/* Copy decimation factor number of new input samples into the state buffer */
i = S->M;
do
{
*pStateCurnt++ = *pSrc++;
} while (--i);
/* Set accumulator to zero */
sum0 = 0.0f;
for(i=0;i<numTaps;i++)
{
/* Read coefficients */
c0 = pCoeffs[i];
/* Fetch 1 state variable */
x0 = pState[i];
/* Perform the multiply-accumulate */
sum0 += x0 * c0;
}
/* Advance the state pointer by the decimation factor
* to process the next group of decimation factor number samples */
pState += S->M;
/* The result is in the accumulator, store in the destination buffer. */
*pDst++ = sum0;
/* Decrement the loop counter */
blkCnt--;
}
/* Processing is complete.
** Now copy the last numTaps - 1 samples to the start of the state buffer.
** This prepares the state buffer for the next function call. */
/* Points to the start of the state buffer */
pStateCurnt = S->pState;
/* Copy numTaps number of values */
i = numTaps - 1U;
/* copy data */
while (i > 0U)
{
*pStateCurnt++ = *pState++;
/* Decrement the loop counter */
i--;
}
}
void ref_fir_decimate_q31(
const arm_fir_decimate_instance_q31 * S,
q31_t * pSrc,
q31_t * pDst,
uint32_t blockSize)
{
q31_t *pState = S->pState; /* State pointer */
q31_t *pCoeffs = S->pCoeffs; /* Coefficient pointer */
q31_t *pStateCurnt; /* Points to the current sample of the state */
q31_t x0, c0; /* Temporary variables to hold state and coefficient values */
q63_t sum0; /* Accumulator */
uint32_t numTaps = S->numTaps; /* Number of taps */
uint32_t i, blkCnt; /* Loop counters */
/* S->pState buffer contains previous frame (numTaps - 1) samples */
/* pStateCurnt points to the location where the new input data should be written */
pStateCurnt = S->pState + numTaps - 1U;
/* Total number of output samples to be computed */
blkCnt = blockSize / S->M;
while (blkCnt > 0U)
{
/* Copy decimation factor number of new input samples into the state buffer */
i = S->M;
do
{
*pStateCurnt++ = *pSrc++;
} while (--i);
/* Set accumulator to zero */
sum0 = 0;
for(i=0;i<numTaps;i++)
{
/* Read coefficients */
c0 = pCoeffs[i];
/* Fetch 1 state variable */
x0 = pState[i];
/* Perform the multiply-accumulate */
sum0 += (q63_t)x0 * c0;
}
/* Advance the state pointer by the decimation factor
* to process the next group of decimation factor number samples */
pState = pState + S->M;
/* The result is in the accumulator, store in the destination buffer. */
*pDst++ = (q31_t) (sum0 >> 31);
/* Decrement the loop counter */
blkCnt--;
}
/* Processing is complete.
** Now copy the last numTaps - 1 samples to the start of the state buffer.
** This prepares the state buffer for the next function call. */
/* Points to the start of the state buffer */
pStateCurnt = S->pState;
i = numTaps - 1U;
/* copy data */
while (i > 0U)
{
*pStateCurnt++ = *pState++;
/* Decrement the loop counter */
i--;
}
}
void ref_fir_decimate_fast_q31(
const arm_fir_decimate_instance_q31 * S,
q31_t * pSrc,
q31_t * pDst,
uint32_t blockSize)
{
q31_t *pState = S->pState; /* State pointer */
q31_t *pCoeffs = S->pCoeffs; /* Coefficient pointer */
q31_t *pStateCurnt; /* Points to the current sample of the state */
q31_t x0, c0; /* Temporary variables to hold state and coefficient values */
q31_t sum0; /* Accumulator */
uint32_t numTaps = S->numTaps; /* Number of taps */
uint32_t i, blkCnt; /* Loop counters */
/* S->pState buffer contains previous frame (numTaps - 1) samples */
/* pStateCurnt points to the location where the new input data should be written */
pStateCurnt = S->pState + numTaps - 1U;
/* Total number of output samples to be computed */
blkCnt = blockSize / S->M;
while (blkCnt > 0U)
{
/* Copy decimation factor number of new input samples into the state buffer */
i = S->M;
do
{
*pStateCurnt++ = *pSrc++;
} while (--i);
/* Set accumulator to zero */
sum0 = 0;
for(i=0;i<numTaps;i++)
{
/* Read coefficients */
c0 = pCoeffs[i];
/* Fetch 1 state variable */
x0 = pState[i];
/* Perform the multiply-accumulate */
sum0 = (q31_t)((((q63_t) sum0 << 32) + ((q63_t) x0 * c0)) >> 32);
}
/* Advance the state pointer by the decimation factor
* to process the next group of decimation factor number samples */
pState = pState + S->M;
/* The result is in the accumulator, store in the destination buffer. */
*pDst++ = (q31_t) (sum0 << 1);
/* Decrement the loop counter */
blkCnt--;
}
/* Processing is complete.
** Now copy the last numTaps - 1 samples to the start of the state buffer.
** This prepares the state buffer for the next function call. */
/* Points to the start of the state buffer */
pStateCurnt = S->pState;
i = numTaps - 1U;
/* copy data */
while (i > 0U)
{
*pStateCurnt++ = *pState++;
/* Decrement the loop counter */
i--;
}
}
void ref_fir_decimate_q15(
const arm_fir_decimate_instance_q15 * S,
q15_t * pSrc,
q15_t * pDst,
uint32_t blockSize)
{
q15_t *pState = S->pState; /* State pointer */
q15_t *pCoeffs = S->pCoeffs; /* Coefficient pointer */
q15_t *pStateCurnt; /* Points to the current sample of the state */
q31_t x0, c0; /* Temporary variables to hold state and coefficient values */
q63_t sum0; /* Accumulator */
uint32_t numTaps = S->numTaps; /* Number of taps */
uint32_t i, blkCnt; /* Loop counters */
/* S->pState buffer contains previous frame (numTaps - 1) samples */
/* pStateCurnt points to the location where the new input data should be written */
pStateCurnt = S->pState + numTaps - 1U;
/* Total number of output samples to be computed */
blkCnt = blockSize / S->M;
while (blkCnt > 0U)
{
/* Copy decimation factor number of new input samples into the state buffer */
i = S->M;
do
{
*pStateCurnt++ = *pSrc++;
} while (--i);
/* Set accumulator to zero */
sum0 = 0;
for(i=0;i<numTaps;i++)
{
/* Read coefficients */
c0 = pCoeffs[i];
/* Fetch 1 state variable */
x0 = pState[i];
/* Perform the multiply-accumulate */
sum0 += (q31_t)x0 * c0;
}
/* Advance the state pointer by the decimation factor
* to process the next group of decimation factor number samples */
pState = pState + S->M;
/* The result is in the accumulator, store in the destination buffer. */
*pDst++ = ref_sat_q15(sum0 >> 15);
/* Decrement the loop counter */
blkCnt--;
}
/* Processing is complete.
** Now copy the last numTaps - 1 samples to the start of the state buffer.
** This prepares the state buffer for the next function call. */
/* Points to the start of the state buffer */
pStateCurnt = S->pState;
i = numTaps - 1U;
/* copy data */
while (i > 0U)
{
*pStateCurnt++ = *pState++;
/* Decrement the loop counter */
i--;
}
}
void ref_fir_decimate_fast_q15(
const arm_fir_decimate_instance_q15 * S,
q15_t * pSrc,
q15_t * pDst,
uint32_t blockSize)
{
q15_t *pState = S->pState; /* State pointer */
q15_t *pCoeffs = S->pCoeffs; /* Coefficient pointer */
q15_t *pStateCurnt; /* Points to the current sample of the state */
q15_t x0, c0; /* Temporary variables to hold state and coefficient values */
q31_t sum0; /* Accumulator */
uint32_t numTaps = S->numTaps; /* Number of taps */
uint32_t i, blkCnt; /* Loop counters */
/* S->pState buffer contains previous frame (numTaps - 1) samples */
/* pStateCurnt points to the location where the new input data should be written */
pStateCurnt = S->pState + numTaps - 1U;
/* Total number of output samples to be computed */
blkCnt = blockSize / S->M;
while (blkCnt > 0U)
{
/* Copy decimation factor number of new input samples into the state buffer */
i = S->M;
do
{
*pStateCurnt++ = *pSrc++;
} while (--i);
/* Set accumulator to zero */
sum0 = 0;
for(i=0;i<numTaps;i++)
{
/* Read coefficients */
c0 = pCoeffs[i];
/* Fetch 1 state variable */
x0 = pState[i];
/* Perform the multiply-accumulate */
sum0 += x0 * c0;
}
/* Advance the state pointer by the decimation factor
* to process the next group of decimation factor number samples */
pState = pState + S->M;
/* The result is in the accumulator, store in the destination buffer. */
*pDst++ = ref_sat_q15(sum0 >> 15);
/* Decrement the loop counter */
blkCnt--;
}
/* Processing is complete.
** Now copy the last numTaps - 1 samples to the start of the state buffer.
** This prepares the state buffer for the next function call. */
/* Points to the start of the state buffer */
pStateCurnt = S->pState;
i = numTaps - 1U;
/* copy data */
while (i > 0U)
{
*pStateCurnt++ = *pState++;
/* Decrement the loop counter */
i--;
}
}
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