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Diffstat (limited to 'DSP_Lib/Source/FilteringFunctions/arm_biquad_cascade_df1_q15.c')
-rw-r--r-- | DSP_Lib/Source/FilteringFunctions/arm_biquad_cascade_df1_q15.c | 411 |
1 files changed, 0 insertions, 411 deletions
diff --git a/DSP_Lib/Source/FilteringFunctions/arm_biquad_cascade_df1_q15.c b/DSP_Lib/Source/FilteringFunctions/arm_biquad_cascade_df1_q15.c deleted file mode 100644 index 8cfc534..0000000 --- a/DSP_Lib/Source/FilteringFunctions/arm_biquad_cascade_df1_q15.c +++ /dev/null @@ -1,411 +0,0 @@ -/* ---------------------------------------------------------------------- -* Copyright (C) 2010-2014 ARM Limited. All rights reserved. -* -* $Date: 19. March 2015 -* $Revision: V.1.4.5 -* -* Project: CMSIS DSP Library -* Title: arm_biquad_cascade_df1_q15.c -* -* Description: Processing function for the -* Q15 Biquad cascade DirectFormI(DF1) filter. -* -* Target Processor: Cortex-M4/Cortex-M3/Cortex-M0 -* -* Redistribution and use in source and binary forms, with or without -* modification, are permitted provided that the following conditions -* are met: -* - Redistributions of source code must retain the above copyright -* notice, this list of conditions and the following disclaimer. -* - Redistributions in binary form must reproduce the above copyright -* notice, this list of conditions and the following disclaimer in -* the documentation and/or other materials provided with the -* distribution. -* - Neither the name of ARM LIMITED nor the names of its contributors -* may be used to endorse or promote products derived from this -* software without specific prior written permission. -* -* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS -* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT -* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS -* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE -* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, -* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, -* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; -* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER -* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT -* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN -* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE -* POSSIBILITY OF SUCH DAMAGE. -* -------------------------------------------------------------------- */ - -#include "arm_math.h" - -/** - * @ingroup groupFilters - */ - -/** - * @addtogroup BiquadCascadeDF1 - * @{ - */ - -/** - * @brief Processing function for the Q15 Biquad cascade filter. - * @param[in] *S points to an instance of the Q15 Biquad cascade structure. - * @param[in] *pSrc points to the block of input data. - * @param[out] *pDst points to the location where the output result is written. - * @param[in] blockSize number of samples to process per call. - * @return none. - * - * - * <b>Scaling and Overflow Behavior:</b> - * \par - * The function is implemented using a 64-bit internal accumulator. - * Both coefficients and state variables are represented in 1.15 format and multiplications yield a 2.30 result. - * The 2.30 intermediate results are accumulated in a 64-bit accumulator in 34.30 format. - * There is no risk of internal overflow with this approach and the full precision of intermediate multiplications is preserved. - * The accumulator is then shifted by <code>postShift</code> bits to truncate the result to 1.15 format by discarding the low 16 bits. - * Finally, the result is saturated to 1.15 format. - * - * \par - * Refer to the function <code>arm_biquad_cascade_df1_fast_q15()</code> for a faster but less precise implementation of this filter for Cortex-M3 and Cortex-M4. - */ - -void arm_biquad_cascade_df1_q15( - const arm_biquad_casd_df1_inst_q15 * S, - q15_t * pSrc, - q15_t * pDst, - uint32_t blockSize) -{ - - -#ifndef ARM_MATH_CM0_FAMILY - - /* Run the below code for Cortex-M4 and Cortex-M3 */ - - q15_t *pIn = pSrc; /* Source pointer */ - q15_t *pOut = pDst; /* Destination pointer */ - q31_t in; /* Temporary variable to hold input value */ - q31_t out; /* Temporary variable to hold output value */ - q31_t b0; /* Temporary variable to hold bo value */ - q31_t b1, a1; /* Filter coefficients */ - q31_t state_in, state_out; /* Filter state variables */ - q31_t acc_l, acc_h; - q63_t acc; /* Accumulator */ - int32_t lShift = (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 */ - int32_t uShift = (32 - lShift); - - do - { - /* Read the b0 and 0 coefficients using SIMD */ - b0 = *__SIMD32(pCoeffs)++; - - /* Read the b1 and b2 coefficients using SIMD */ - b1 = *__SIMD32(pCoeffs)++; - - /* Read the a1 and a2 coefficients using SIMD */ - a1 = *__SIMD32(pCoeffs)++; - - /* Read the input state values from the state buffer: x[n-1], x[n-2] */ - state_in = *__SIMD32(pState)++; - - /* Read the output state values from the state buffer: y[n-1], y[n-2] */ - state_out = *__SIMD32(pState)--; - - /* Apply loop unrolling and compute 2 output values simultaneously. */ - /* The variable acc hold output values that are being computed: - * - * acc = b0 * x[n] + b1 * x[n-1] + b2 * x[n-2] + a1 * y[n-1] + a2 * y[n-2] - * acc = b0 * x[n] + b1 * x[n-1] + b2 * x[n-2] + a1 * y[n-1] + a2 * y[n-2] - */ - sample = blockSize >> 1u; - - /* First part of the processing with loop unrolling. Compute 2 outputs at a time. - ** a second loop below computes the remaining 1 sample. */ - while(sample > 0u) - { - - /* Read the input */ - in = *__SIMD32(pIn)++; - - /* out = b0 * x[n] + 0 * 0 */ - out = __SMUAD(b0, in); - - /* acc += b1 * x[n-1] + b2 * x[n-2] + out */ - acc = __SMLALD(b1, state_in, out); - /* acc += a1 * y[n-1] + a2 * y[n-2] */ - acc = __SMLALD(a1, state_out, acc); - - /* The result is converted from 3.29 to 1.31 if postShift = 1, and then saturation is applied */ - /* 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 */ - out = (uint32_t) acc_l >> lShift | acc_h << uShift; - - out = __SSAT(out, 16); - - /* 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 */ - /* x[n-N], x[n-N-1] are packed together to make state_in of type q31 */ - /* y[n-N], y[n-N-1] are packed together to make state_out of type q31 */ - -#ifndef ARM_MATH_BIG_ENDIAN - - state_in = __PKHBT(in, state_in, 16); - state_out = __PKHBT(out, state_out, 16); - -#else - - state_in = __PKHBT(state_in >> 16, (in >> 16), 16); - state_out = __PKHBT(state_out >> 16, (out), 16); - -#endif /* #ifndef ARM_MATH_BIG_ENDIAN */ - - /* out = b0 * x[n] + 0 * 0 */ - out = __SMUADX(b0, in); - /* acc += b1 * x[n-1] + b2 * x[n-2] + out */ - acc = __SMLALD(b1, state_in, out); - /* acc += a1 * y[n-1] + a2 * y[n-2] */ - acc = __SMLALD(a1, state_out, acc); - - /* The result is converted from 3.29 to 1.31 if postShift = 1, and then saturation is applied */ - /* 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 */ - out = (uint32_t) acc_l >> lShift | acc_h << uShift; - - out = __SSAT(out, 16); - - /* Store the output in the destination buffer. */ - -#ifndef ARM_MATH_BIG_ENDIAN - - *__SIMD32(pOut)++ = __PKHBT(state_out, out, 16); - -#else - - *__SIMD32(pOut)++ = __PKHBT(out, state_out >> 16, 16); - -#endif /* #ifndef ARM_MATH_BIG_ENDIAN */ - - /* 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 */ - /* x[n-N], x[n-N-1] are packed together to make state_in of type q31 */ - /* y[n-N], y[n-N-1] are packed together to make state_out of type q31 */ -#ifndef ARM_MATH_BIG_ENDIAN - - state_in = __PKHBT(in >> 16, state_in, 16); - state_out = __PKHBT(out, state_out, 16); - -#else - - state_in = __PKHBT(state_in >> 16, in, 16); - state_out = __PKHBT(state_out >> 16, out, 16); - -#endif /* #ifndef ARM_MATH_BIG_ENDIAN */ - - - /* Decrement the loop counter */ - sample--; - - } - - /* If the blockSize is not a multiple of 2, compute any remaining output samples here. - ** No loop unrolling is used. */ - - if((blockSize & 0x1u) != 0u) - { - /* Read the input */ - in = *pIn++; - - /* out = b0 * x[n] + 0 * 0 */ - -#ifndef ARM_MATH_BIG_ENDIAN - - out = __SMUAD(b0, in); - -#else - - out = __SMUADX(b0, in); - -#endif /* #ifndef ARM_MATH_BIG_ENDIAN */ - - /* acc = b1 * x[n-1] + b2 * x[n-2] + out */ - acc = __SMLALD(b1, state_in, out); - /* acc += a1 * y[n-1] + a2 * y[n-2] */ - acc = __SMLALD(a1, state_out, acc); - - /* The result is converted from 3.29 to 1.31 if postShift = 1, and then saturation is applied */ - /* 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 */ - out = (uint32_t) acc_l >> lShift | acc_h << uShift; - - out = __SSAT(out, 16); - - /* Store the output in the destination buffer. */ - *pOut++ = (q15_t) out; - - /* 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 */ - /* x[n-N], x[n-N-1] are packed together to make state_in of type q31 */ - /* y[n-N], y[n-N-1] are packed together to make state_out of type q31 */ - -#ifndef ARM_MATH_BIG_ENDIAN - - state_in = __PKHBT(in, state_in, 16); - state_out = __PKHBT(out, state_out, 16); - -#else - - state_in = __PKHBT(state_in >> 16, in, 16); - state_out = __PKHBT(state_out >> 16, out, 16); - -#endif /* #ifndef ARM_MATH_BIG_ENDIAN */ - - } - - /* The first stage goes from the input wire to the output wire. */ - /* Subsequent numStages occur in-place in the output wire */ - pIn = pDst; - - /* Reset the output pointer */ - pOut = pDst; - - /* Store the updated state variables back into the state array */ - *__SIMD32(pState)++ = state_in; - *__SIMD32(pState)++ = state_out; - - - /* Decrement the loop counter */ - stage--; - - } while(stage > 0u); - -#else - - /* Run the below code for Cortex-M0 */ - - 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]; - - /* 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 = (q31_t) b0 *Xn; - - /* acc += b1 * x[n-1] */ - acc += (q31_t) b1 *Xn1; - /* acc += b[2] * x[n-2] */ - acc += (q31_t) b2 *Xn2; - /* acc += a1 * y[n-1] */ - acc += (q31_t) a1 *Yn1; - /* acc += a2 * y[n-2] */ - acc += (q31_t) a2 *Yn2; - - /* The result is converted to 1.31 */ - acc = __SSAT((acc >> shift), 16); - - /* 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 = (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); - -#endif /* #ifndef ARM_MATH_CM0_FAMILY */ - -} - - -/** - * @} end of BiquadCascadeDF1 group - */ |