| /* |
| * Copyright (c) 2017, Alliance for Open Media. All rights reserved |
| * |
| * This source code is subject to the terms of the BSD 2 Clause License and |
| * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License |
| * was not distributed with this source code in the LICENSE file, you can |
| * obtain it at www.aomedia.org/license/software. If the Alliance for Open |
| * Media Patent License 1.0 was not distributed with this source code in the |
| * PATENTS file, you can obtain it at www.aomedia.org/license/patent. |
| */ |
| |
| #ifndef AOM_DSP_NOISE_UTIL_H_ |
| #define AOM_DSP_NOISE_UTIL_H_ |
| |
| #ifdef __cplusplus |
| extern "C" { |
| #endif // __cplusplus |
| |
| // aom_noise_tx_t is an abstraction of a transform that is used for denoising. |
| // It is meant to be lightweight and does hold the transformed data (as |
| // the user should not be manipulating the transformed data directly). |
| struct aom_noise_tx_t; |
| |
| // Allocates and returns a aom_noise_tx_t useful for denoising the given |
| // block_size. The resulting aom_noise_tx_t should be free'd with |
| // aom_noise_tx_free. |
| struct aom_noise_tx_t *aom_noise_tx_malloc(int block_size); |
| void aom_noise_tx_free(struct aom_noise_tx_t *aom_noise_tx); |
| |
| // Transforms the internal data and holds it in the aom_noise_tx's internal |
| // buffer. For compatibility with existing SIMD implementations, "data" must |
| // be 32-byte aligned. |
| void aom_noise_tx_forward(struct aom_noise_tx_t *aom_noise_tx, |
| const float *data); |
| |
| // Filters aom_noise_tx's internal data using the provided noise power spectral |
| // density. The PSD must be at least block_size * block_size and should be |
| // populated with a constant or via estimates taken from |
| // aom_noise_tx_add_energy. |
| void aom_noise_tx_filter(struct aom_noise_tx_t *aom_noise_tx, const float *psd); |
| |
| // Performs an inverse transform using the internal transform data. |
| // For compatibility with existing SIMD implementations, "data" must be 32-byte |
| // aligned. |
| void aom_noise_tx_inverse(struct aom_noise_tx_t *aom_noise_tx, float *data); |
| |
| // Aggregates the power of the buffered transform data into the psd buffer. |
| void aom_noise_tx_add_energy(const struct aom_noise_tx_t *aom_noise_tx, |
| float *psd); |
| |
| // Returns a default value suitable for denosing a transform of the given |
| // block_size. The noise "factor" determines the strength of the noise to |
| // be removed. A value of about 2.5 can be used for moderate denoising, |
| // where a value of 5.0 can be used for a high level of denoising. |
| float aom_noise_psd_get_default_value(int block_size, float factor); |
| |
| // Computes normalized cross correlation of two vectors a and b of length n. |
| double aom_normalized_cross_correlation(const double *a, const double *b, |
| int n); |
| |
| // Validates the correlated noise in the data buffer of size (w, h). |
| int aom_noise_data_validate(const double *data, int w, int h); |
| |
| #ifdef __cplusplus |
| } // extern "C" |
| #endif // __cplusplus |
| |
| #endif // AOM_DSP_NOISE_UTIL_H_ |