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|
#include "ref.h"
void ref_biquad_cascade_df2T_f32(
const arm_biquad_cascade_df2T_instance_f32 * S,
float32_t * pSrc,
float32_t * pDst,
uint32_t blockSize)
{
float32_t *pIn = pSrc; /* source pointer */
float32_t *pOut = pDst; /* destination pointer */
float32_t *pState = S->pState; /* State pointer */
float32_t *pCoeffs = S->pCoeffs; /* coefficient pointer */
float32_t acc; /* accumulator */
float32_t b0, b1, b2, a1, a2; /* Filter coefficients */
float32_t Xn; /* temporary input */
float32_t d1, d2; /* state variables */
uint32_t sample, stage = S->numStages; /* loop counters */
do
{
/* Reading the coefficients */
b0 = *pCoeffs++;
b1 = *pCoeffs++;
b2 = *pCoeffs++;
a1 = *pCoeffs++;
a2 = *pCoeffs++;
/*Reading the state values */
d1 = pState[0];
d2 = pState[1];
sample = blockSize;
while (sample > 0U)
{
/* Read the input */
Xn = *pIn++;
/* y[n] = b0 * x[n] + d1 */
acc = (b0 * Xn) + d1;
/* Store the result in the accumulator in the destination buffer. */
*pOut++ = acc;
/* Every time after the output is computed state should be updated. */
/* d1 = b1 * x[n] + a1 * y[n] + d2 */
d1 = (b1 * Xn + a1 * acc) + d2;
/* d2 = b2 * x[n] + a2 * y[n] */
d2 = (b2 * Xn) + (a2 * acc);
/* decrement the loop counter */
sample--;
}
/* Store the updated state variables back into the state array */
*pState++ = d1;
*pState++ = d2;
/* The current stage input is given as the output to the next stage */
pIn = pDst;
/*Reset the output working pointer */
pOut = pDst;
/* decrement the loop counter */
stage--;
} while (stage > 0U);
}
void ref_biquad_cascade_stereo_df2T_f32(
const arm_biquad_cascade_stereo_df2T_instance_f32 * S,
float32_t * pSrc,
float32_t * pDst,
uint32_t blockSize)
{
float32_t *pIn = pSrc; /* source pointer */
float32_t *pOut = pDst; /* destination pointer */
float32_t *pState = S->pState; /* State pointer */
float32_t *pCoeffs = S->pCoeffs; /* coefficient pointer */
float32_t acc1a, acc1b; /* accumulator */
float32_t b0, b1, b2, a1, a2; /* Filter coefficients */
float32_t Xn1a, Xn1b; /* temporary input */
float32_t d1a, d2a, d1b, d2b; /* state variables */
uint32_t sample, stage = S->numStages; /* loop counters */
do
{
/* Reading the coefficients */
b0 = *pCoeffs++;
b1 = *pCoeffs++;
b2 = *pCoeffs++;
a1 = *pCoeffs++;
a2 = *pCoeffs++;
/*Reading the state values */
d1a = pState[0];
d2a = pState[1];
d1b = pState[2];
d2b = pState[3];
sample = blockSize;
while (sample > 0U)
{
/* Read the input */
Xn1a = *pIn++; //Channel a
Xn1b = *pIn++; //Channel b
/* y[n] = b0 * x[n] + d1 */
acc1a = (b0 * Xn1a) + d1a;
acc1b = (b0 * Xn1b) + d1b;
/* Store the result in the accumulator in the destination buffer. */
*pOut++ = acc1a;
*pOut++ = acc1b;
/* Every time after the output is computed state should be updated. */
/* d1 = b1 * x[n] + a1 * y[n] + d2 */
d1a = ((b1 * Xn1a) + (a1 * acc1a)) + d2a;
d1b = ((b1 * Xn1b) + (a1 * acc1b)) + d2b;
/* d2 = b2 * x[n] + a2 * y[n] */
d2a = (b2 * Xn1a) + (a2 * acc1a);
d2b = (b2 * Xn1b) + (a2 * acc1b);
/* decrement the loop counter */
sample--;
}
/* Store the updated state variables back into the state array */
*pState++ = d1a;
*pState++ = d2a;
*pState++ = d1b;
*pState++ = d2b;
/* The current stage input is given as the output to the next stage */
pIn = pDst;
/*Reset the output working pointer */
pOut = pDst;
/* decrement the loop counter */
stage--;
} while (stage > 0U);
}
void ref_biquad_cascade_df2T_f64(
const arm_biquad_cascade_df2T_instance_f64 * S,
float64_t * pSrc,
float64_t * pDst,
uint32_t blockSize)
{
float64_t *pIn = pSrc; /* source pointer */
float64_t *pOut = pDst; /* destination pointer */
float64_t *pState = S->pState; /* State pointer */
float64_t *pCoeffs = S->pCoeffs; /* coefficient pointer */
float64_t acc; /* accumulator */
float64_t b0, b1, b2, a1, a2; /* Filter coefficients */
float64_t Xn; /* temporary input */
float64_t d1, d2; /* state variables */
uint32_t sample, stage = S->numStages; /* loop counters */
do
{
/* Reading the coefficients */
b0 = *pCoeffs++;
b1 = *pCoeffs++;
b2 = *pCoeffs++;
a1 = *pCoeffs++;
a2 = *pCoeffs++;
/*Reading the state values */
d1 = pState[0];
d2 = pState[1];
sample = blockSize;
while (sample > 0U)
{
/* Read the input */
Xn = *pIn++;
/* y[n] = b0 * x[n] + d1 */
acc = (b0 * Xn) + d1;
/* Store the result in the accumulator in the destination buffer. */
*pOut++ = acc;
/* Every time after the output is computed state should be updated. */
/* d1 = b1 * x[n] + a1 * y[n] + d2 */
d1 = (b1 * Xn + a1 * acc) + d2;
/* d2 = b2 * x[n] + a2 * y[n] */
d2 = (b2 * Xn) + (a2 * acc);
/* decrement the loop counter */
sample--;
}
/* Store the updated state variables back into the state array */
*pState++ = d1;
*pState++ = d2;
/* The current stage input is given as the output to the next stage */
pIn = pDst;
/*Reset the output working pointer */
pOut = pDst;
/* decrement the loop counter */
stage--;
} while (stage > 0U);
}
void ref_biquad_cascade_df1_f32(
const arm_biquad_casd_df1_inst_f32 * S,
float32_t * pSrc,
float32_t * pDst,
uint32_t blockSize)
{
float32_t *pIn = pSrc; /* source pointer */
float32_t *pOut = pDst; /* destination pointer */
float32_t *pState = S->pState; /* pState pointer */
float32_t *pCoeffs = S->pCoeffs; /* coefficient pointer */
float32_t acc; /* Simulates the accumulator */
float32_t b0, b1, b2, a1, a2; /* Filter coefficients */
float32_t Xn1, Xn2, Yn1, Yn2; /* Filter pState variables */
float32_t Xn; /* temporary input */
uint32_t sample, stage = S->numStages; /* loop counters */
do
{
/* Reading the coefficients */
b0 = *pCoeffs++;
b1 = *pCoeffs++;
b2 = *pCoeffs++;
a1 = *pCoeffs++;
a2 = *pCoeffs++;
/* Reading the pState values */
Xn1 = pState[0];
Xn2 = pState[1];
Yn1 = pState[2];
Yn2 = pState[3];
/* The variables acc holds the output value that is computed:
* acc = b0 * x[n] + b1 * x[n-1] + b2 * x[n-2] + a1 * y[n-1] + a2 * y[n-2]
*/
sample = blockSize;
while (sample > 0U)
{
/* Read the input */
Xn = *pIn++;
/* acc = b0 * x[n] + b1 * x[n-1] + b2 * x[n-2] + a1 * y[n-1] + a2 * y[n-2] */
acc = (b0 * Xn) + (b1 * Xn1) + (b2 * Xn2) + (a1 * Yn1) + (a2 * Yn2);
/* Store the result in the accumulator in the destination buffer. */
*pOut++ = acc;
/* Every time after the output is computed state should be updated. */
/* The states should be updated as: */
/* Xn2 = Xn1 */
/* Xn1 = Xn */
/* Yn2 = Yn1 */
/* Yn1 = acc */
Xn2 = Xn1;
Xn1 = Xn;
Yn2 = Yn1;
Yn1 = acc;
/* decrement the loop counter */
sample--;
}
/* Store the updated state variables back into the pState array */
*pState++ = Xn1;
*pState++ = Xn2;
*pState++ = Yn1;
*pState++ = Yn2;
/* The first stage goes from the input buffer to the output buffer. */
/* Subsequent numStages occur in-place in the output buffer */
pIn = pDst;
/* Reset the output pointer */
pOut = pDst;
/* decrement the loop counter */
stage--;
} while (stage > 0U);
}
void ref_biquad_cas_df1_32x64_q31(
const arm_biquad_cas_df1_32x64_ins_q31 * S,
q31_t * pSrc,
q31_t * pDst,
uint32_t blockSize)
{
q31_t *pIn = pSrc; /* input pointer initialization */
q31_t *pOut = pDst; /* output pointer initialization */
q63_t *pState = S->pState; /* state pointer initialization */
q31_t *pCoeffs = S->pCoeffs; /* coeff pointer initialization */
q63_t acc; /* accumulator */
q31_t Xn1, Xn2; /* Input Filter state variables */
q63_t Yn1, Yn2; /* Output Filter state variables */
q31_t b0, b1, b2, a1, a2; /* Filter coefficients */
q31_t Xn; /* temporary input */
int32_t shift = (int32_t) S->postShift + 1; /* Shift to be applied to the output */
uint32_t sample, stage = S->numStages; /* loop counters */
q31_t acc_l, acc_h; /* temporary output */
uint32_t uShift = ((uint32_t) S->postShift + 1U);
uint32_t lShift = 32U - uShift; /* Shift to be applied to the output */
do
{
/* Reading the coefficients */
b0 = *pCoeffs++;
b1 = *pCoeffs++;
b2 = *pCoeffs++;
a1 = *pCoeffs++;
a2 = *pCoeffs++;
/* Reading the state values */
Xn1 = pState[0];
Xn2 = pState[1];
Yn1 = pState[2];
Yn2 = pState[3];
sample = blockSize;
while (sample > 0U)
{
/* Read the input */
Xn = *pIn++;
/* acc = b0 * x[n] + b1 * x[n-1] + b2 * x[n-2] + a1 * y[n-1] + a2 * y[n-2] */
acc = (q63_t)Xn*b0 + (q63_t)Xn1*b1 + (q63_t)Xn2*b2;
/* acc += a1 * y[n-1] */
acc += mult32x64(Yn1, a1);
/* acc += a2 * y[n-2] */
acc += mult32x64(Yn2, a2);
/* Every time after the output is computed state should be updated. */
Xn2 = Xn1;
Xn1 = Xn;
Yn2 = Yn1;
/* The result is converted to 1.63, Yn1 variable is reused */
Yn1 = acc << shift;
/* Calc lower part of acc */
acc_l = acc & 0xffffffff;
/* Calc upper part of acc */
acc_h = (acc >> 32) & 0xffffffff;
/* Apply shift for lower part of acc and upper part of acc */
acc_h = (uint32_t) acc_l >> lShift | acc_h << uShift;
/* Store the output in the destination buffer in 1.31 format. */
*pOut++ = acc_h;
/* decrement the loop counter */
sample--;
}
/* The first stage output is given as input to the second stage. */
pIn = pDst;
/* Reset to destination buffer working pointer */
pOut = pDst;
/* Store the updated state variables back into the pState array */
*pState++ = (q63_t) Xn1;
*pState++ = (q63_t) Xn2;
*pState++ = Yn1;
*pState++ = Yn2;
} while (--stage);
}
void ref_biquad_cascade_df1_q31(
const arm_biquad_casd_df1_inst_q31 * S,
q31_t * pSrc,
q31_t * pDst,
uint32_t blockSize)
{
q63_t acc; /* accumulator */
uint32_t uShift = ((uint32_t) S->postShift + 1U);
uint32_t lShift = 32U - uShift; /* Shift to be applied to the output */
q31_t *pIn = pSrc; /* input pointer initialization */
q31_t *pOut = pDst; /* output pointer initialization */
q31_t *pState = S->pState; /* pState pointer initialization */
q31_t *pCoeffs = S->pCoeffs; /* coeff pointer initialization */
q31_t Xn1, Xn2, Yn1, Yn2; /* Filter state variables */
q31_t b0, b1, b2, a1, a2; /* Filter coefficients */
q31_t Xn; /* temporary input */
uint32_t sample, stage = S->numStages; /* loop counters */
do
{
/* Reading the coefficients */
b0 = *pCoeffs++;
b1 = *pCoeffs++;
b2 = *pCoeffs++;
a1 = *pCoeffs++;
a2 = *pCoeffs++;
/* Reading the state values */
Xn1 = pState[0];
Xn2 = pState[1];
Yn1 = pState[2];
Yn2 = pState[3];
/* The variables acc holds the output value that is computed:
* acc = b0 * x[n] + b1 * x[n-1] + b2 * x[n-2] + a1 * y[n-1] + a2 * y[n-2]
*/
sample = blockSize;
while (sample > 0U)
{
/* Read the input */
Xn = *pIn++;
/* acc = b0 * x[n] + b1 * x[n-1] + b2 * x[n-2] + a1 * y[n-1] + a2 * y[n-2] */
/* acc = b0 * x[n] */
acc = (q63_t) b0 *Xn;
/* acc += b1 * x[n-1] */
acc += (q63_t) b1 *Xn1;
/* acc += b[2] * x[n-2] */
acc += (q63_t) b2 *Xn2;
/* acc += a1 * y[n-1] */
acc += (q63_t) a1 *Yn1;
/* acc += a2 * y[n-2] */
acc += (q63_t) a2 *Yn2;
/* The result is converted to 1.31 */
acc = acc >> lShift;
/* Every time after the output is computed state should be updated. */
/* The states should be updated as: */
/* Xn2 = Xn1 */
/* Xn1 = Xn */
/* Yn2 = Yn1 */
/* Yn1 = acc */
Xn2 = Xn1;
Xn1 = Xn;
Yn2 = Yn1;
Yn1 = (q31_t) acc;
/* Store the output in the destination buffer. */
*pOut++ = (q31_t) acc;
/* decrement the loop counter */
sample--;
}
/* The first stage goes from the input buffer to the output buffer. */
/* Subsequent stages occur in-place in the output buffer */
pIn = pDst;
/* Reset to destination pointer */
pOut = pDst;
/* Store the updated state variables back into the pState array */
*pState++ = Xn1;
*pState++ = Xn2;
*pState++ = Yn1;
*pState++ = Yn2;
} while (--stage);
}
void ref_biquad_cascade_df1_fast_q31(
const arm_biquad_casd_df1_inst_q31 * S,
q31_t * pSrc,
q31_t * pDst,
uint32_t blockSize)
{
q31_t acc = 0; /* accumulator */
q31_t Xn1, Xn2, Yn1, Yn2; /* Filter state variables */
q31_t b0, b1, b2, a1, a2; /* Filter coefficients */
q31_t *pIn = pSrc; /* input pointer initialization */
q31_t *pOut = pDst; /* output pointer initialization */
q31_t *pState = S->pState; /* pState pointer initialization */
q31_t *pCoeffs = S->pCoeffs; /* coeff pointer initialization */
q31_t Xn; /* temporary input */
int32_t shift = (int32_t) S->postShift + 1; /* Shift to be applied to the output */
uint32_t sample, stage = S->numStages; /* loop counters */
do
{
/* Reading the coefficients */
b0 = *pCoeffs++;
b1 = *pCoeffs++;
b2 = *pCoeffs++;
a1 = *pCoeffs++;
a2 = *pCoeffs++;
/* Reading the state values */
Xn1 = pState[0];
Xn2 = pState[1];
Yn1 = pState[2];
Yn2 = pState[3];
sample = blockSize;
while (sample > 0U)
{
/* Read the input */
Xn = *pIn++;
/* acc = b0 * x[n] + b1 * x[n-1] + b2 * x[n-2] + a1 * y[n-1] + a2 * y[n-2] */
mult_32x32_keep32_R(acc, b0, Xn);
multAcc_32x32_keep32_R(acc, b1, Xn1);
multAcc_32x32_keep32_R(acc, b2, Xn2);
multAcc_32x32_keep32_R(acc, a1, Yn1);
multAcc_32x32_keep32_R(acc, a2, Yn2);
/* The result is converted to 1.31 */
acc <<= shift;
/* Every time after the output is computed state should be updated. */
Xn2 = Xn1;
Xn1 = Xn;
Yn2 = Yn1;
Yn1 = acc;
/* Store the output in the destination buffer. */
*pOut++ = acc;
/* decrement the loop counter */
sample--;
}
/* The first stage goes from the input buffer to the output buffer. */
/* Subsequent stages occur in-place in the output buffer */
pIn = pDst;
/* Reset to destination pointer */
pOut = pDst;
/* Store the updated state variables back into the pState array */
*pState++ = Xn1;
*pState++ = Xn2;
*pState++ = Yn1;
*pState++ = Yn2;
} while (--stage);
}
void ref_biquad_cascade_df1_fast_q15(
const arm_biquad_casd_df1_inst_q15 * S,
q15_t * pSrc,
q15_t * pDst,
uint32_t blockSize)
{
q15_t *pIn = pSrc; /* Source pointer */
q15_t *pOut = pDst; /* Destination pointer */
q15_t b0, b1, b2, a1, a2; /* Filter coefficients */
q15_t Xn1, Xn2, Yn1, Yn2; /* Filter state variables */
q15_t Xn; /* temporary input */
q31_t acc; /* Accumulator */
int32_t shift = (15 - (int32_t) S->postShift); /* Post shift */
q15_t *pState = S->pState; /* State pointer */
q15_t *pCoeffs = S->pCoeffs; /* Coefficient pointer */
uint32_t sample, stage = (uint32_t) S->numStages; /* Stage loop counter */
do
{
/* Reading the coefficients */
b0 = *pCoeffs++;
pCoeffs++; // skip the 0 coefficient
b1 = *pCoeffs++;
b2 = *pCoeffs++;
a1 = *pCoeffs++;
a2 = *pCoeffs++;
/* Reading the state values */
Xn1 = pState[0];
Xn2 = pState[1];
Yn1 = pState[2];
Yn2 = pState[3];
sample = blockSize;
while (sample > 0U)
{
/* Read the input */
Xn = *pIn++;
/* acc = b0 * x[n] + b1 * x[n-1] + b2 * x[n-2] + a1 * y[n-1] + a2 * y[n-2] */
acc = (q31_t)b0*Xn + (q31_t)b1*Xn1 + (q31_t)b2*Xn2 + (q31_t)a1*Yn1 + (q31_t)a2*Yn2;
/* The result is converted to 1.15 */
acc = ref_sat_q15(acc >> shift);
/* Every time after the output is computed state should be updated. */
Xn2 = Xn1;
Xn1 = Xn;
Yn2 = Yn1;
Yn1 = (q15_t) acc;
/* Store the output in the destination buffer. */
*pOut++ = (q15_t) acc;
/* decrement the loop counter */
sample--;
}
/* The first stage goes from the input buffer to the output buffer. */
/* Subsequent stages occur in-place in the output buffer */
pIn = pDst;
/* Reset to destination pointer */
pOut = pDst;
/* Store the updated state variables back into the pState array */
*pState++ = Xn1;
*pState++ = Xn2;
*pState++ = Yn1;
*pState++ = Yn2;
} while (--stage);
}
void ref_biquad_cascade_df1_q15(
const arm_biquad_casd_df1_inst_q15 * S,
q15_t * pSrc,
q15_t * pDst,
uint32_t blockSize)
{
q15_t *pIn = pSrc; /* Source pointer */
q15_t *pOut = pDst; /* Destination pointer */
q15_t b0, b1, b2, a1, a2; /* Filter coefficients */
q15_t Xn1, Xn2, Yn1, Yn2; /* Filter state variables */
q15_t Xn; /* temporary input */
q63_t acc; /* Accumulator */
int32_t shift = (15 - (int32_t) S->postShift); /* Post shift */
q15_t *pState = S->pState; /* State pointer */
q15_t *pCoeffs = S->pCoeffs; /* Coefficient pointer */
uint32_t sample, stage = (uint32_t) S->numStages; /* Stage loop counter */
do
{
/* Reading the coefficients */
b0 = *pCoeffs++;
pCoeffs++; // skip the 0 coefficient
b1 = *pCoeffs++;
b2 = *pCoeffs++;
a1 = *pCoeffs++;
a2 = *pCoeffs++;
/* Reading the state values */
Xn1 = pState[0];
Xn2 = pState[1];
Yn1 = pState[2];
Yn2 = pState[3];
sample = blockSize;
while (sample > 0U)
{
/* Read the input */
Xn = *pIn++;
/* acc = b0 * x[n] + b1 * x[n-1] + b2 * x[n-2] + a1 * y[n-1] + a2 * y[n-2] */
acc = (q31_t)b0*Xn + (q31_t)b1*Xn1 + (q31_t)b2*Xn2 + (q31_t)a1*Yn1 + (q31_t)a2*Yn2;
/* The result is converted to 1.15 */
acc = ref_sat_q15(acc >> shift);
/* Every time after the output is computed state should be updated. */
Xn2 = Xn1;
Xn1 = Xn;
Yn2 = Yn1;
Yn1 = (q15_t) acc;
/* Store the output in the destination buffer. */
*pOut++ = (q15_t) acc;
/* decrement the loop counter */
sample--;
}
/* The first stage goes from the input buffer to the output buffer. */
/* Subsequent stages occur in-place in the output buffer */
pIn = pDst;
/* Reset to destination pointer */
pOut = pDst;
/* Store the updated state variables back into the pState array */
*pState++ = Xn1;
*pState++ = Xn2;
*pState++ = Yn1;
*pState++ = Yn2;
} while (--stage);
}
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