mirror of https://github.com/FFmpeg/FFmpeg.git
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
121 lines
4.8 KiB
121 lines
4.8 KiB
/* |
|
* AC-3 DSP functions |
|
* Copyright (c) 2011 Justin Ruggles |
|
* |
|
* 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 |
|
*/ |
|
|
|
#ifndef AVCODEC_AC3DSP_H |
|
#define AVCODEC_AC3DSP_H |
|
|
|
#include <stdint.h> |
|
|
|
/** |
|
* Number of mantissa bits written for each bap value. |
|
* bap values with fractional bits are set to 0 and are calculated separately. |
|
*/ |
|
extern const uint16_t ff_ac3_bap_bits[16]; |
|
|
|
typedef struct AC3DSPContext { |
|
/** |
|
* Set each encoded exponent in a block to the minimum of itself and the |
|
* exponents in the same frequency bin of up to 5 following blocks. |
|
* @param exp pointer to the start of the current block of exponents. |
|
* constraints: align 16 |
|
* @param num_reuse_blocks number of blocks that will reuse exponents from the current block. |
|
* constraints: range 0 to 5 |
|
* @param nb_coefs number of frequency coefficients. |
|
*/ |
|
void (*ac3_exponent_min)(uint8_t *exp, int num_reuse_blocks, int nb_coefs); |
|
|
|
/** |
|
* Convert an array of float in range [-1.0,1.0] to int32_t with range |
|
* [-(1<<24),(1<<24)] |
|
* |
|
* @param dst destination array of int32_t. |
|
* constraints: 16-byte aligned |
|
* @param src source array of float. |
|
* constraints: 16-byte aligned |
|
* @param len number of elements to convert. |
|
* constraints: multiple of 32 greater than zero |
|
*/ |
|
void (*float_to_fixed24)(int32_t *dst, const float *src, unsigned int len); |
|
|
|
/** |
|
* Calculate bit allocation pointers. |
|
* The SNR is the difference between the masking curve and the signal. AC-3 |
|
* uses this value for each frequency bin to allocate bits. The snroffset |
|
* parameter is a global adjustment to the SNR for all bins. |
|
* |
|
* @param[in] mask masking curve |
|
* @param[in] psd signal power for each frequency bin |
|
* @param[in] start starting bin location |
|
* @param[in] end ending bin location |
|
* @param[in] snr_offset SNR adjustment |
|
* @param[in] floor noise floor |
|
* @param[in] bap_tab look-up table for bit allocation pointers |
|
* @param[out] bap bit allocation pointers |
|
*/ |
|
void (*bit_alloc_calc_bap)(int16_t *mask, int16_t *psd, int start, int end, |
|
int snr_offset, int floor, |
|
const uint8_t *bap_tab, uint8_t *bap); |
|
|
|
/** |
|
* Update bap counts using the supplied array of bap. |
|
* |
|
* @param[out] mant_cnt bap counts for 1 block |
|
* @param[in] bap array of bap, pointing to start coef bin |
|
* @param[in] len number of elements to process |
|
*/ |
|
void (*update_bap_counts)(uint16_t mant_cnt[16], uint8_t *bap, int len); |
|
|
|
/** |
|
* Calculate the number of bits needed to encode a set of mantissas. |
|
* |
|
* @param[in] mant_cnt bap counts for all blocks |
|
* @return mantissa bit count |
|
*/ |
|
int (*compute_mantissa_size)(uint16_t mant_cnt[6][16]); |
|
|
|
void (*extract_exponents)(uint8_t *exp, int32_t *coef, int nb_coefs); |
|
|
|
void (*sum_square_butterfly_int32)(int64_t sum[4], const int32_t *coef0, |
|
const int32_t *coef1, int len); |
|
|
|
void (*sum_square_butterfly_float)(float sum[4], const float *coef0, |
|
const float *coef1, int len); |
|
|
|
int out_channels; |
|
int in_channels; |
|
void (*downmix)(float **samples, float **matrix, int len); |
|
void (*downmix_fixed)(int32_t **samples, int16_t **matrix, int len); |
|
} AC3DSPContext; |
|
|
|
void ff_ac3dsp_init (AC3DSPContext *c); |
|
void ff_ac3dsp_init_arm(AC3DSPContext *c); |
|
void ff_ac3dsp_init_x86(AC3DSPContext *c); |
|
void ff_ac3dsp_init_mips(AC3DSPContext *c); |
|
void ff_ac3dsp_init_riscv(AC3DSPContext *c); |
|
|
|
void ff_ac3dsp_downmix(AC3DSPContext *c, float **samples, float **matrix, |
|
int out_ch, int in_ch, int len); |
|
void ff_ac3dsp_downmix_fixed(AC3DSPContext *c, int32_t **samples, int16_t **matrix, |
|
int out_ch, int in_ch, int len); |
|
|
|
void ff_ac3dsp_set_downmix_x86(AC3DSPContext *c); |
|
|
|
#endif /* AVCODEC_AC3DSP_H */
|
|
|