FFmpeg  4.4.4
ac3dsp.h
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1 /*
2  * AC-3 DSP functions
3  * Copyright (c) 2011 Justin Ruggles
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #ifndef AVCODEC_AC3DSP_H
23 #define AVCODEC_AC3DSP_H
24 
25 #include <stdint.h>
26 
27 /**
28  * Number of mantissa bits written for each bap value.
29  * bap values with fractional bits are set to 0 and are calculated separately.
30  */
31 extern const uint16_t ff_ac3_bap_bits[16];
32 
33 typedef struct AC3DSPContext {
34  /**
35  * Set each encoded exponent in a block to the minimum of itself and the
36  * exponents in the same frequency bin of up to 5 following blocks.
37  * @param exp pointer to the start of the current block of exponents.
38  * constraints: align 16
39  * @param num_reuse_blocks number of blocks that will reuse exponents from the current block.
40  * constraints: range 0 to 5
41  * @param nb_coefs number of frequency coefficients.
42  */
43  void (*ac3_exponent_min)(uint8_t *exp, int num_reuse_blocks, int nb_coefs);
44 
45  /**
46  * Convert an array of float in range [-1.0,1.0] to int32_t with range
47  * [-(1<<24),(1<<24)]
48  *
49  * @param dst destination array of int32_t.
50  * constraints: 16-byte aligned
51  * @param src source array of float.
52  * constraints: 16-byte aligned
53  * @param len number of elements to convert.
54  * constraints: multiple of 32 greater than zero
55  */
56  void (*float_to_fixed24)(int32_t *dst, const float *src, unsigned int len);
57 
58  /**
59  * Calculate bit allocation pointers.
60  * The SNR is the difference between the masking curve and the signal. AC-3
61  * uses this value for each frequency bin to allocate bits. The snroffset
62  * parameter is a global adjustment to the SNR for all bins.
63  *
64  * @param[in] mask masking curve
65  * @param[in] psd signal power for each frequency bin
66  * @param[in] start starting bin location
67  * @param[in] end ending bin location
68  * @param[in] snr_offset SNR adjustment
69  * @param[in] floor noise floor
70  * @param[in] bap_tab look-up table for bit allocation pointers
71  * @param[out] bap bit allocation pointers
72  */
73  void (*bit_alloc_calc_bap)(int16_t *mask, int16_t *psd, int start, int end,
74  int snr_offset, int floor,
75  const uint8_t *bap_tab, uint8_t *bap);
76 
77  /**
78  * Update bap counts using the supplied array of bap.
79  *
80  * @param[out] mant_cnt bap counts for 1 block
81  * @param[in] bap array of bap, pointing to start coef bin
82  * @param[in] len number of elements to process
83  */
84  void (*update_bap_counts)(uint16_t mant_cnt[16], uint8_t *bap, int len);
85 
86  /**
87  * Calculate the number of bits needed to encode a set of mantissas.
88  *
89  * @param[in] mant_cnt bap counts for all blocks
90  * @return mantissa bit count
91  */
92  int (*compute_mantissa_size)(uint16_t mant_cnt[6][16]);
93 
94  void (*extract_exponents)(uint8_t *exp, int32_t *coef, int nb_coefs);
95 
96  void (*sum_square_butterfly_int32)(int64_t sum[4], const int32_t *coef0,
97  const int32_t *coef1, int len);
98 
99  void (*sum_square_butterfly_float)(float sum[4], const float *coef0,
100  const float *coef1, int len);
101 
104  void (*downmix)(float **samples, float **matrix, int len);
105  void (*downmix_fixed)(int32_t **samples, int16_t **matrix, int len);
106 } AC3DSPContext;
107 
108 void ff_ac3dsp_init (AC3DSPContext *c, int bit_exact);
109 void ff_ac3dsp_init_arm(AC3DSPContext *c, int bit_exact);
110 void ff_ac3dsp_init_x86(AC3DSPContext *c, int bit_exact);
111 void ff_ac3dsp_init_mips(AC3DSPContext *c, int bit_exact);
112 
113 void ff_ac3dsp_downmix(AC3DSPContext *c, float **samples, float **matrix,
114  int out_ch, int in_ch, int len);
115 void ff_ac3dsp_downmix_fixed(AC3DSPContext *c, int32_t **samples, int16_t **matrix,
116  int out_ch, int in_ch, int len);
117 
119 
120 #endif /* AVCODEC_AC3DSP_H */
void ff_ac3dsp_set_downmix_x86(AC3DSPContext *c)
Definition: ac3dsp_init.c:89
void ff_ac3dsp_init_arm(AC3DSPContext *c, int bit_exact)
void ff_ac3dsp_downmix_fixed(AC3DSPContext *c, int32_t **samples, int16_t **matrix, int out_ch, int in_ch, int len)
Definition: ac3dsp.c:309
void ff_ac3dsp_downmix(AC3DSPContext *c, float **samples, float **matrix, int out_ch, int in_ch, int len)
Definition: ac3dsp.c:336
void ff_ac3dsp_init(AC3DSPContext *c, int bit_exact)
Definition: ac3dsp.c:368
const uint16_t ff_ac3_bap_bits[16]
Number of mantissa bits written for each bap value.
Definition: ac3dsp.c:99
void ff_ac3dsp_init_mips(AC3DSPContext *c, int bit_exact)
Definition: ac3dsp_mips.c:403
void ff_ac3dsp_init_x86(AC3DSPContext *c, int bit_exact)
Definition: ac3dsp_init.c:42
uint8_t
int32_t
static __device__ float floor(float a)
Definition: cuda_runtime.h:173
static const uint8_t bap_tab[64]
Definition: dolby_e.c:589
int8_t exp
Definition: eval.c:72
int
static const uint16_t mask[17]
Definition: lzw.c:38
typedef void(RENAME(mix_any_func_type))
int out_channels
Definition: ac3dsp.h:102
void(* sum_square_butterfly_float)(float sum[4], const float *coef0, const float *coef1, int len)
Definition: ac3dsp.h:99
void(* sum_square_butterfly_int32)(int64_t sum[4], const int32_t *coef0, const int32_t *coef1, int len)
Definition: ac3dsp.h:96
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)
Calculate bit allocation pointers.
Definition: ac3dsp.h:73
void(* downmix)(float **samples, float **matrix, int len)
Definition: ac3dsp.h:104
void(* extract_exponents)(uint8_t *exp, int32_t *coef, int nb_coefs)
Definition: ac3dsp.h:94
void(* float_to_fixed24)(int32_t *dst, const float *src, unsigned int len)
Convert an array of float in range [-1.0,1.0] to int32_t with range [-(1<<24),(1<<24)].
Definition: ac3dsp.h:56
void(* ac3_exponent_min)(uint8_t *exp, int num_reuse_blocks, int nb_coefs)
Set each encoded exponent in a block to the minimum of itself and the exponents in the same frequency...
Definition: ac3dsp.h:43
void(* update_bap_counts)(uint16_t mant_cnt[16], uint8_t *bap, int len)
Update bap counts using the supplied array of bap.
Definition: ac3dsp.h:84
int in_channels
Definition: ac3dsp.h:103
int(* compute_mantissa_size)(uint16_t mant_cnt[6][16])
Calculate the number of bits needed to encode a set of mantissas.
Definition: ac3dsp.h:92
void(* downmix_fixed)(int32_t **samples, int16_t **matrix, int len)
Definition: ac3dsp.h:105
#define src
Definition: vp8dsp.c:255
int len
static double c[64]