Laxmi Kant Tiwari / mbed-dsp

CMSIS DSP Lib

Fork of mbed-dsp by mbed official

cmsis_dsp/StatisticsFunctions/arm_min_q31.c@2:da51fb522205, 2013-05-30 (annotated)

Committer:
emilmont
Date:
Thu May 30 17:10:11 2013 +0100
Revision:
2:da51fb522205
Parent:
1:fdd22bb7aa52
Child:
3:7a284390b0ce
Keep "cmsis-dsp" module in synch with its source

Who changed what in which revision?

UserRevisionLine numberNew contents of line
emilmont 1:fdd22bb7aa52 1 /* ----------------------------------------------------------------------
emilmont 1:fdd22bb7aa52 2 * Copyright (C) 2010 ARM Limited. All rights reserved.
emilmont 1:fdd22bb7aa52 3 *
emilmont 1:fdd22bb7aa52 4 * $Date: 15. February 2012
emilmont 2:da51fb522205 5 * $Revision: V1.1.0
emilmont 1:fdd22bb7aa52 6 *
emilmont 2:da51fb522205 7 * Project: CMSIS DSP Library
emilmont 2:da51fb522205 8 * Title: arm_min_q31.c
emilmont 1:fdd22bb7aa52 9 *
emilmont 2:da51fb522205 10 * Description: Minimum value of a Q31 vector.
emilmont 1:fdd22bb7aa52 11 *
emilmont 1:fdd22bb7aa52 12 * Target Processor: Cortex-M4/Cortex-M3/Cortex-M0
emilmont 1:fdd22bb7aa52 13 *
emilmont 1:fdd22bb7aa52 14 * Version 1.1.0 2012/02/15
emilmont 1:fdd22bb7aa52 15 * Updated with more optimizations, bug fixes and minor API changes.
emilmont 1:fdd22bb7aa52 16 *
emilmont 1:fdd22bb7aa52 17 * Version 1.0.10 2011/7/15
emilmont 1:fdd22bb7aa52 18 * Big Endian support added and Merged M0 and M3/M4 Source code.
emilmont 1:fdd22bb7aa52 19 *
emilmont 1:fdd22bb7aa52 20 * Version 1.0.3 2010/11/29
emilmont 1:fdd22bb7aa52 21 * Re-organized the CMSIS folders and updated documentation.
emilmont 1:fdd22bb7aa52 22 *
emilmont 1:fdd22bb7aa52 23 * Version 1.0.2 2010/11/11
emilmont 1:fdd22bb7aa52 24 * Documentation updated.
emilmont 1:fdd22bb7aa52 25 *
emilmont 1:fdd22bb7aa52 26 * Version 1.0.1 2010/10/05
emilmont 1:fdd22bb7aa52 27 * Production release and review comments incorporated.
emilmont 1:fdd22bb7aa52 28 *
emilmont 1:fdd22bb7aa52 29 * Version 1.0.0 2010/09/20
emilmont 1:fdd22bb7aa52 30 * Production release and review comments incorporated.
emilmont 1:fdd22bb7aa52 31 * ---------------------------------------------------------------------------- */
emilmont 1:fdd22bb7aa52 32
emilmont 1:fdd22bb7aa52 33 #include "arm_math.h"
emilmont 1:fdd22bb7aa52 34
emilmont 1:fdd22bb7aa52 35 /**
emilmont 1:fdd22bb7aa52 36 * @ingroup groupStats
emilmont 1:fdd22bb7aa52 37 */
emilmont 1:fdd22bb7aa52 38
emilmont 1:fdd22bb7aa52 39
emilmont 1:fdd22bb7aa52 40 /**
emilmont 1:fdd22bb7aa52 41 * @addtogroup Min
emilmont 1:fdd22bb7aa52 42 * @{
emilmont 1:fdd22bb7aa52 43 */
emilmont 1:fdd22bb7aa52 44
emilmont 1:fdd22bb7aa52 45
emilmont 1:fdd22bb7aa52 46 /**
emilmont 1:fdd22bb7aa52 47 * @brief Minimum value of a Q31 vector.
emilmont 1:fdd22bb7aa52 48 * @param[in] *pSrc points to the input vector
emilmont 1:fdd22bb7aa52 49 * @param[in] blockSize length of the input vector
emilmont 1:fdd22bb7aa52 50 * @param[out] *pResult minimum value returned here
emilmont 1:fdd22bb7aa52 51 * @param[out] *pIndex index of minimum value returned here
emilmont 1:fdd22bb7aa52 52 * @return none.
emilmont 1:fdd22bb7aa52 53 *
emilmont 1:fdd22bb7aa52 54 */
emilmont 1:fdd22bb7aa52 55
emilmont 1:fdd22bb7aa52 56 void arm_min_q31(
emilmont 1:fdd22bb7aa52 57 q31_t * pSrc,
emilmont 1:fdd22bb7aa52 58 uint32_t blockSize,
emilmont 1:fdd22bb7aa52 59 q31_t * pResult,
emilmont 1:fdd22bb7aa52 60 uint32_t * pIndex)
emilmont 1:fdd22bb7aa52 61 {
emilmont 1:fdd22bb7aa52 62 #ifndef ARM_MATH_CM0
emilmont 1:fdd22bb7aa52 63
emilmont 1:fdd22bb7aa52 64 /* Run the below code for Cortex-M4 and Cortex-M3 */
emilmont 1:fdd22bb7aa52 65 q31_t minVal1, minVal2, out; /* Temporary variables to store the output value. */
emilmont 1:fdd22bb7aa52 66 uint32_t blkCnt, outIndex, count; /* loop counter */
emilmont 1:fdd22bb7aa52 67
emilmont 1:fdd22bb7aa52 68 /* Initialise the count value. */
emilmont 1:fdd22bb7aa52 69 count = 0u;
emilmont 1:fdd22bb7aa52 70 /* Initialise the index value to zero. */
emilmont 1:fdd22bb7aa52 71 outIndex = 0u;
emilmont 1:fdd22bb7aa52 72 /* Load first input value that act as reference value for comparision */
emilmont 1:fdd22bb7aa52 73 out = *pSrc++;
emilmont 1:fdd22bb7aa52 74
emilmont 1:fdd22bb7aa52 75
emilmont 1:fdd22bb7aa52 76 /* Loop unrolling */
emilmont 1:fdd22bb7aa52 77 blkCnt = (blockSize - 1u) >> 2u;
emilmont 1:fdd22bb7aa52 78
emilmont 1:fdd22bb7aa52 79 while(blkCnt > 0)
emilmont 1:fdd22bb7aa52 80 {
emilmont 1:fdd22bb7aa52 81 /* Initialize minVal to the next consecutive values one by one */
emilmont 1:fdd22bb7aa52 82 minVal1 = *pSrc++;
emilmont 1:fdd22bb7aa52 83 minVal2 = *pSrc++;
emilmont 1:fdd22bb7aa52 84
emilmont 1:fdd22bb7aa52 85 /* compare for the minimum value */
emilmont 1:fdd22bb7aa52 86 if(out > minVal1)
emilmont 1:fdd22bb7aa52 87 {
emilmont 1:fdd22bb7aa52 88 /* Update the minimum value and its index */
emilmont 1:fdd22bb7aa52 89 out = minVal1;
emilmont 1:fdd22bb7aa52 90 outIndex = count + 1u;
emilmont 1:fdd22bb7aa52 91 }
emilmont 1:fdd22bb7aa52 92
emilmont 1:fdd22bb7aa52 93 minVal1 = *pSrc++;
emilmont 1:fdd22bb7aa52 94
emilmont 1:fdd22bb7aa52 95 /* compare for the minimum value */
emilmont 1:fdd22bb7aa52 96 if(out > minVal2)
emilmont 1:fdd22bb7aa52 97 {
emilmont 1:fdd22bb7aa52 98 /* Update the minimum value and its index */
emilmont 1:fdd22bb7aa52 99 out = minVal2;
emilmont 1:fdd22bb7aa52 100 outIndex = count + 2u;
emilmont 1:fdd22bb7aa52 101 }
emilmont 1:fdd22bb7aa52 102
emilmont 1:fdd22bb7aa52 103 minVal2 = *pSrc++;
emilmont 1:fdd22bb7aa52 104
emilmont 1:fdd22bb7aa52 105 /* compare for the minimum value */
emilmont 1:fdd22bb7aa52 106 if(out > minVal1)
emilmont 1:fdd22bb7aa52 107 {
emilmont 1:fdd22bb7aa52 108 /* Update the minimum value and its index */
emilmont 1:fdd22bb7aa52 109 out = minVal1;
emilmont 1:fdd22bb7aa52 110 outIndex = count + 3u;
emilmont 1:fdd22bb7aa52 111 }
emilmont 1:fdd22bb7aa52 112
emilmont 1:fdd22bb7aa52 113 /* compare for the minimum value */
emilmont 1:fdd22bb7aa52 114 if(out > minVal2)
emilmont 1:fdd22bb7aa52 115 {
emilmont 1:fdd22bb7aa52 116 /* Update the minimum value and its index */
emilmont 1:fdd22bb7aa52 117 out = minVal2;
emilmont 1:fdd22bb7aa52 118 outIndex = count + 4u;
emilmont 1:fdd22bb7aa52 119 }
emilmont 1:fdd22bb7aa52 120
emilmont 1:fdd22bb7aa52 121 count += 4u;
emilmont 1:fdd22bb7aa52 122
emilmont 1:fdd22bb7aa52 123 blkCnt--;
emilmont 1:fdd22bb7aa52 124 }
emilmont 1:fdd22bb7aa52 125
emilmont 1:fdd22bb7aa52 126 /* if (blockSize - 1u ) is not multiple of 4 */
emilmont 1:fdd22bb7aa52 127 blkCnt = (blockSize - 1u) % 4u;
emilmont 1:fdd22bb7aa52 128
emilmont 1:fdd22bb7aa52 129 #else
emilmont 1:fdd22bb7aa52 130
emilmont 1:fdd22bb7aa52 131 /* Run the below code for Cortex-M0 */
emilmont 1:fdd22bb7aa52 132 q31_t minVal1, out; /* Temporary variables to store the output value. */
emilmont 1:fdd22bb7aa52 133 uint32_t blkCnt, outIndex; /* loop counter */
emilmont 1:fdd22bb7aa52 134
emilmont 1:fdd22bb7aa52 135 blkCnt = (blockSize - 1u);
emilmont 1:fdd22bb7aa52 136
emilmont 1:fdd22bb7aa52 137 /* Initialise the index value to zero. */
emilmont 1:fdd22bb7aa52 138 outIndex = 0u;
emilmont 1:fdd22bb7aa52 139 /* Load first input value that act as reference value for comparision */
emilmont 1:fdd22bb7aa52 140 out = *pSrc++;
emilmont 1:fdd22bb7aa52 141
emilmont 1:fdd22bb7aa52 142 #endif // #ifndef ARM_MATH_CM0
emilmont 1:fdd22bb7aa52 143
emilmont 1:fdd22bb7aa52 144 while(blkCnt > 0)
emilmont 1:fdd22bb7aa52 145 {
emilmont 1:fdd22bb7aa52 146 /* Initialize minVal to the next consecutive values one by one */
emilmont 1:fdd22bb7aa52 147 minVal1 = *pSrc++;
emilmont 1:fdd22bb7aa52 148
emilmont 1:fdd22bb7aa52 149 /* compare for the minimum value */
emilmont 1:fdd22bb7aa52 150 if(out > minVal1)
emilmont 1:fdd22bb7aa52 151 {
emilmont 1:fdd22bb7aa52 152 /* Update the minimum value and it's index */
emilmont 1:fdd22bb7aa52 153 out = minVal1;
emilmont 1:fdd22bb7aa52 154 outIndex = blockSize - blkCnt;
emilmont 1:fdd22bb7aa52 155 }
emilmont 1:fdd22bb7aa52 156
emilmont 1:fdd22bb7aa52 157 blkCnt--;
emilmont 1:fdd22bb7aa52 158
emilmont 1:fdd22bb7aa52 159 }
emilmont 1:fdd22bb7aa52 160
emilmont 1:fdd22bb7aa52 161 /* Store the minimum value and its index into destination pointers */
emilmont 1:fdd22bb7aa52 162 *pResult = out;
emilmont 1:fdd22bb7aa52 163 *pIndex = outIndex;
emilmont 1:fdd22bb7aa52 164 }
emilmont 1:fdd22bb7aa52 165
emilmont 1:fdd22bb7aa52 166 /**
emilmont 1:fdd22bb7aa52 167 * @} end of Min group
emilmont 1:fdd22bb7aa52 168 */