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Diffstat (limited to 'third_party/libwebrtc/common_audio/vad/vad_gmm.h')
| -rw-r--r-- | third_party/libwebrtc/common_audio/vad/vad_gmm.h | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/third_party/libwebrtc/common_audio/vad/vad_gmm.h b/third_party/libwebrtc/common_audio/vad/vad_gmm.h new file mode 100644 index 0000000000..ada5189756 --- /dev/null +++ b/third_party/libwebrtc/common_audio/vad/vad_gmm.h @@ -0,0 +1,39 @@ +/* + * Copyright (c) 2011 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. + */ + +// Gaussian probability calculations internally used in vad_core.c. + +#ifndef COMMON_AUDIO_VAD_VAD_GMM_H_ +#define COMMON_AUDIO_VAD_VAD_GMM_H_ + +#include <stdint.h> + +// Calculates the probability for `input`, given that `input` comes from a +// normal distribution with mean and standard deviation (`mean`, `std`). +// +// Inputs: +// - input : input sample in Q4. +// - mean : mean input in the statistical model, Q7. +// - std : standard deviation, Q7. +// +// Output: +// +// - delta : input used when updating the model, Q11. +// `delta` = (`input` - `mean`) / `std`^2. +// +// Return: +// (probability for `input`) = +// 1 / `std` * exp(-(`input` - `mean`)^2 / (2 * `std`^2)); +int32_t WebRtcVad_GaussianProbability(int16_t input, + int16_t mean, + int16_t std, + int16_t* delta); + +#endif // COMMON_AUDIO_VAD_VAD_GMM_H_ |