1 files changed, 114 insertions, 0 deletions
diff --git a/Drivers/CMSIS/DSP/Source/StatisticsFunctions/arm_mean_q15.c b/Drivers/CMSIS/DSP/Source/StatisticsFunctions/arm_mean_q15.c
new file mode 100644
index 0000000..09e6da9
--- /dev/null
+++ b/Drivers/CMSIS/DSP/Source/StatisticsFunctions/arm_mean_q15.c
@@ -0,0 +1,114 @@
+/* ----------------------------------------------------------------------
+ * Project:      CMSIS DSP Library
+ * Title:        arm_mean_q15.c
+ * Description:  Mean value of a Q15 vector
+ *
+ * $Date:        18. March 2019
+ * $Revision:    V1.6.0
+ *
+ * Target Processor: Cortex-M cores
+ * -------------------------------------------------------------------- */
+/*
+ * Copyright (C) 2010-2019 ARM Limited or its affiliates. All rights reserved.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Licensed under the Apache License, Version 2.0 (the License); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an AS IS BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "arm_math.h"
+
+/**
+  @ingroup groupStats
+ */
+
+/**
+  @addtogroup mean
+  @{
+ */
+
+/**
+  @brief         Mean value of a Q15 vector.
+  @param[in]     pSrc       points to the input vector
+  @param[in]     blockSize  number of samples in input vector
+  @param[out]    pResult    mean value returned here
+  @return        none
+
+  @par           Scaling and Overflow Behavior
+                   The function is implemented using a 32-bit internal accumulator.
+                   The input is represented in 1.15 format and is accumulated in a 32-bit
+                   accumulator in 17.15 format.
+                   There is no risk of internal overflow with this approach, and the
+                   full precision of intermediate result is preserved.
+                   Finally, the accumulator is truncated to yield a result of 1.15 format.
+ */
+
+void arm_mean_q15(
+  const q15_t * pSrc,
+        uint32_t blockSize,
+        q15_t * pResult)
+{
+        uint32_t blkCnt;                               /* Loop counter */
+        q31_t sum = 0;                                 /* Temporary result storage */
+
+#if defined (ARM_MATH_LOOPUNROLL)
+        q31_t in;
+#endif
+
+#if defined (ARM_MATH_LOOPUNROLL)
+
+  /* Loop unrolling: Compute 4 outputs at a time */
+  blkCnt = blockSize >> 2U;
+
+  while (blkCnt > 0U)
+  {
+    /* C = (A[0] + A[1] + A[2] + ... + A[blockSize-1]) */
+    in = read_q15x2_ia ((q15_t **) &pSrc);
+    sum += ((in << 16U) >> 16U);
+    sum +=  (in >> 16U);
+
+    in = read_q15x2_ia ((q15_t **) &pSrc);
+    sum += ((in << 16U) >> 16U);
+    sum +=  (in >> 16U);
+
+    /* Decrement the loop counter */
+    blkCnt--;
+  }
+
+  /* Loop unrolling: Compute remaining outputs */
+  blkCnt = blockSize % 0x4U;
+
+#else
+
+  /* Initialize blkCnt with number of samples */
+  blkCnt = blockSize;
+
+#endif /* #if defined (ARM_MATH_LOOPUNROLL) */
+
+  while (blkCnt > 0U)
+  {
+    /* C = (A[0] + A[1] + A[2] + ... + A[blockSize-1]) */
+    sum += *pSrc++;
+
+    /* Decrement loop counter */
+    blkCnt--;
+  }
+
+  /* C = (A[0] + A[1] + A[2] + ... + A[blockSize-1]) / blockSize  */
+  /* Store result to destination */
+  *pResult = (q15_t) (sum / (int32_t) blockSize);
+}
+
+/**
+  @} end of mean group
+ */