#include "libavutil/lls.h"#include "dsputil.h"#include "lpc.h"Go to the source code of this file.
Defines | |
| #define | LPC_USE_DOUBLE |
| LPC utility code Copyright (c) 2006 Justin Ruggles <justin.ruggles@gmail.com>. | |
Functions | |
| static void | apply_welch_window (const int32_t *data, int len, double *w_data) |
| Apply Welch window function to audio block. | |
| void | ff_lpc_compute_autocorr (const int32_t *data, int len, int lag, double *autoc) |
| Calculates autocorrelation data from audio samples A Welch window function is applied before calculation. | |
| static void | quantize_lpc_coefs (double *lpc_in, int order, int precision, int32_t *lpc_out, int *shift, int max_shift, int zero_shift) |
| Quantize LPC coefficients. | |
| static int | estimate_best_order (double *ref, int min_order, int max_order) |
| int | ff_lpc_calc_coefs (DSPContext *s, const int32_t *samples, int blocksize, int min_order, int max_order, int precision, int32_t coefs[][MAX_LPC_ORDER], int *shift, int use_lpc, int omethod, int max_shift, int zero_shift) |
| Calculate LPC coefficients for multiple orders. | |
| #define LPC_USE_DOUBLE |
LPC utility code Copyright (c) 2006 Justin Ruggles <justin.ruggles@gmail.com>.
This file is part of FFmpeg.
FFmpeg is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version.
FFmpeg is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License along with FFmpeg; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
| static void apply_welch_window | ( | const int32_t * | data, | |
| int | len, | |||
| double * | w_data | |||
| ) | [static] |
Apply Welch window function to audio block.
Definition at line 32 of file lpc.c.
Referenced by ff_lpc_compute_autocorr().
| static int estimate_best_order | ( | double * | ref, | |
| int | min_order, | |||
| int | max_order | |||
| ) | [static] |
| int ff_lpc_calc_coefs | ( | DSPContext * | s, | |
| const int32_t * | samples, | |||
| int | blocksize, | |||
| int | min_order, | |||
| int | max_order, | |||
| int | precision, | |||
| int32_t | coefs[][MAX_LPC_ORDER], | |||
| int * | shift, | |||
| int | use_lpc, | |||
| int | omethod, | |||
| int | max_shift, | |||
| int | zero_shift | |||
| ) |
Calculate LPC coefficients for multiple orders.
| use_lpc | LPC method for determining coefficients 0 = LPC with fixed pre-defined coeffs 1 = LPC with coeffs determined by Levinson-Durbin recursion 2+ = LPC with coeffs determined by Cholesky factorization using (use_lpc-1) passes. |
Definition at line 165 of file lpc.c.
Referenced by calc_predictor_params(), and encode_residual().
| void ff_lpc_compute_autocorr | ( | const int32_t * | data, | |
| int | len, | |||
| int | lag, | |||
| double * | autoc | |||
| ) |
Calculates autocorrelation data from audio samples A Welch window function is applied before calculation.
Definition at line 58 of file lpc.c.
Referenced by dsputil_init().
| static void quantize_lpc_coefs | ( | double * | lpc_in, | |
| int | order, | |||
| int | precision, | |||
| int32_t * | lpc_out, | |||
| int * | shift, | |||
| int | max_shift, | |||
| int | zero_shift | |||
| ) | [static] |
1.5.8