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Diffstat (limited to 'third_party/libwebrtc/common_audio/signal_processing/min_max_operations.c')
-rw-r--r-- | third_party/libwebrtc/common_audio/signal_processing/min_max_operations.c | 256 |
1 files changed, 256 insertions, 0 deletions
diff --git a/third_party/libwebrtc/common_audio/signal_processing/min_max_operations.c b/third_party/libwebrtc/common_audio/signal_processing/min_max_operations.c new file mode 100644 index 0000000000..1b9542e7ef --- /dev/null +++ b/third_party/libwebrtc/common_audio/signal_processing/min_max_operations.c @@ -0,0 +1,256 @@ +/* + * Copyright (c) 2012 The WebRTC project authors. All Rights Reserved. + * + * Use of this source code is governed by a BSD-style license + * that can be found in the LICENSE file in the root of the source + * tree. An additional intellectual property rights grant can be found + * in the file PATENTS. All contributing project authors may + * be found in the AUTHORS file in the root of the source tree. + */ + +/* + * This file contains the implementation of functions + * WebRtcSpl_MaxAbsValueW16C() + * WebRtcSpl_MaxAbsValueW32C() + * WebRtcSpl_MaxValueW16C() + * WebRtcSpl_MaxValueW32C() + * WebRtcSpl_MinValueW16C() + * WebRtcSpl_MinValueW32C() + * WebRtcSpl_MaxAbsIndexW16() + * WebRtcSpl_MaxIndexW16() + * WebRtcSpl_MaxIndexW32() + * WebRtcSpl_MinIndexW16() + * WebRtcSpl_MinIndexW32() + * + */ + +#include <stdlib.h> + +#include "rtc_base/checks.h" +#include "common_audio/signal_processing/include/signal_processing_library.h" + +// TODO(bjorn/kma): Consolidate function pairs (e.g. combine +// WebRtcSpl_MaxAbsValueW16C and WebRtcSpl_MaxAbsIndexW16 into a single one.) +// TODO(kma): Move the next six functions into min_max_operations_c.c. + +// Maximum absolute value of word16 vector. C version for generic platforms. +int16_t WebRtcSpl_MaxAbsValueW16C(const int16_t* vector, size_t length) { + size_t i = 0; + int absolute = 0, maximum = 0; + + RTC_DCHECK_GT(length, 0); + + for (i = 0; i < length; i++) { + absolute = abs((int)vector[i]); + + if (absolute > maximum) { + maximum = absolute; + } + } + + // Guard the case for abs(-32768). + if (maximum > WEBRTC_SPL_WORD16_MAX) { + maximum = WEBRTC_SPL_WORD16_MAX; + } + + return (int16_t)maximum; +} + +// Maximum absolute value of word32 vector. C version for generic platforms. +int32_t WebRtcSpl_MaxAbsValueW32C(const int32_t* vector, size_t length) { + // Use uint32_t for the local variables, to accommodate the return value + // of abs(0x80000000), which is 0x80000000. + + uint32_t absolute = 0, maximum = 0; + size_t i = 0; + + RTC_DCHECK_GT(length, 0); + + for (i = 0; i < length; i++) { + absolute = abs((int)vector[i]); + if (absolute > maximum) { + maximum = absolute; + } + } + + maximum = WEBRTC_SPL_MIN(maximum, WEBRTC_SPL_WORD32_MAX); + + return (int32_t)maximum; +} + +// Maximum value of word16 vector. C version for generic platforms. +int16_t WebRtcSpl_MaxValueW16C(const int16_t* vector, size_t length) { + int16_t maximum = WEBRTC_SPL_WORD16_MIN; + size_t i = 0; + + RTC_DCHECK_GT(length, 0); + + for (i = 0; i < length; i++) { + if (vector[i] > maximum) + maximum = vector[i]; + } + return maximum; +} + +// Maximum value of word32 vector. C version for generic platforms. +int32_t WebRtcSpl_MaxValueW32C(const int32_t* vector, size_t length) { + int32_t maximum = WEBRTC_SPL_WORD32_MIN; + size_t i = 0; + + RTC_DCHECK_GT(length, 0); + + for (i = 0; i < length; i++) { + if (vector[i] > maximum) + maximum = vector[i]; + } + return maximum; +} + +// Minimum value of word16 vector. C version for generic platforms. +int16_t WebRtcSpl_MinValueW16C(const int16_t* vector, size_t length) { + int16_t minimum = WEBRTC_SPL_WORD16_MAX; + size_t i = 0; + + RTC_DCHECK_GT(length, 0); + + for (i = 0; i < length; i++) { + if (vector[i] < minimum) + minimum = vector[i]; + } + return minimum; +} + +// Minimum value of word32 vector. C version for generic platforms. +int32_t WebRtcSpl_MinValueW32C(const int32_t* vector, size_t length) { + int32_t minimum = WEBRTC_SPL_WORD32_MAX; + size_t i = 0; + + RTC_DCHECK_GT(length, 0); + + for (i = 0; i < length; i++) { + if (vector[i] < minimum) + minimum = vector[i]; + } + return minimum; +} + +// Index of maximum absolute value in a word16 vector. +size_t WebRtcSpl_MaxAbsIndexW16(const int16_t* vector, size_t length) { + // Use type int for local variables, to accomodate the value of abs(-32768). + + size_t i = 0, index = 0; + int absolute = 0, maximum = 0; + + RTC_DCHECK_GT(length, 0); + + for (i = 0; i < length; i++) { + absolute = abs((int)vector[i]); + + if (absolute > maximum) { + maximum = absolute; + index = i; + } + } + + return index; +} + +int16_t WebRtcSpl_MaxAbsElementW16(const int16_t* vector, size_t length) { + int16_t min_val, max_val; + WebRtcSpl_MinMaxW16(vector, length, &min_val, &max_val); + if (min_val == max_val || min_val < -max_val) { + return min_val; + } + return max_val; +} + +// Index of maximum value in a word16 vector. +size_t WebRtcSpl_MaxIndexW16(const int16_t* vector, size_t length) { + size_t i = 0, index = 0; + int16_t maximum = WEBRTC_SPL_WORD16_MIN; + + RTC_DCHECK_GT(length, 0); + + for (i = 0; i < length; i++) { + if (vector[i] > maximum) { + maximum = vector[i]; + index = i; + } + } + + return index; +} + +// Index of maximum value in a word32 vector. +size_t WebRtcSpl_MaxIndexW32(const int32_t* vector, size_t length) { + size_t i = 0, index = 0; + int32_t maximum = WEBRTC_SPL_WORD32_MIN; + + RTC_DCHECK_GT(length, 0); + + for (i = 0; i < length; i++) { + if (vector[i] > maximum) { + maximum = vector[i]; + index = i; + } + } + + return index; +} + +// Index of minimum value in a word16 vector. +size_t WebRtcSpl_MinIndexW16(const int16_t* vector, size_t length) { + size_t i = 0, index = 0; + int16_t minimum = WEBRTC_SPL_WORD16_MAX; + + RTC_DCHECK_GT(length, 0); + + for (i = 0; i < length; i++) { + if (vector[i] < minimum) { + minimum = vector[i]; + index = i; + } + } + + return index; +} + +// Index of minimum value in a word32 vector. +size_t WebRtcSpl_MinIndexW32(const int32_t* vector, size_t length) { + size_t i = 0, index = 0; + int32_t minimum = WEBRTC_SPL_WORD32_MAX; + + RTC_DCHECK_GT(length, 0); + + for (i = 0; i < length; i++) { + if (vector[i] < minimum) { + minimum = vector[i]; + index = i; + } + } + + return index; +} + +// Finds both the minimum and maximum elements in an array of 16-bit integers. +void WebRtcSpl_MinMaxW16(const int16_t* vector, size_t length, + int16_t* min_val, int16_t* max_val) { +#if defined(WEBRTC_HAS_NEON) + return WebRtcSpl_MinMaxW16Neon(vector, length, min_val, max_val); +#else + int16_t minimum = WEBRTC_SPL_WORD16_MAX; + int16_t maximum = WEBRTC_SPL_WORD16_MIN; + size_t i = 0; + + RTC_DCHECK_GT(length, 0); + + for (i = 0; i < length; i++) { + if (vector[i] < minimum) + minimum = vector[i]; + if (vector[i] > maximum) + maximum = vector[i]; + } + *min_val = minimum; + *max_val = maximum; +#endif +} |