#include <stdint.h>#include "dsputil.h"Go to the source code of this file.
Defines | |
| #define | ORDER_METHOD_EST 0 |
| LPC utility code Copyright (c) 2006 Justin Ruggles <justin.ruggles@gmail.com>. | |
| #define | ORDER_METHOD_2LEVEL 1 |
| #define | ORDER_METHOD_4LEVEL 2 |
| #define | ORDER_METHOD_8LEVEL 3 |
| #define | ORDER_METHOD_SEARCH 4 |
| #define | ORDER_METHOD_LOG 5 |
| #define | MIN_LPC_ORDER 1 |
| #define | MAX_LPC_ORDER 32 |
| #define | LPC_TYPE float |
Functions | |
| 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. | |
| 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 int | compute_lpc_coefs (const LPC_TYPE *autoc, int max_order, LPC_TYPE *lpc, int lpc_stride, int fail, int normalize) |
| Levinson-Durbin recursion. | |
| #define LPC_TYPE float |
| #define MAX_LPC_ORDER 32 |
Definition at line 36 of file lpc.h.
Referenced by calc_predictor_params(), encode_residual(), and flac_encode_init().
| #define MIN_LPC_ORDER 1 |
Definition at line 35 of file lpc.h.
Referenced by alac_encode_init(), ff_lpc_calc_coefs(), and flac_encode_init().
| #define ORDER_METHOD_2LEVEL 1 |
| #define ORDER_METHOD_4LEVEL 2 |
| #define ORDER_METHOD_8LEVEL 3 |
| #define ORDER_METHOD_EST 0 |
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
Definition at line 28 of file lpc.h.
Referenced by calc_predictor_params(), ff_lpc_calc_coefs(), and flac_encode_init().
| #define ORDER_METHOD_LOG 5 |
| #define ORDER_METHOD_SEARCH 4 |
| static int compute_lpc_coefs | ( | const LPC_TYPE * | autoc, | |
| int | max_order, | |||
| LPC_TYPE * | lpc, | |||
| int | lpc_stride, | |||
| int | fail, | |||
| int | normalize | |||
| ) | [inline, static] |
Levinson-Durbin recursion.
Produces LPC coefficients from autocorrelation data.
Definition at line 61 of file lpc.h.
Referenced by apply_tns(), backward_filter(), and ff_lpc_calc_coefs().
| 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().
1.5.8