2 * AC-3 encoder & E-AC-3 encoder common header
3 * Copyright (c) 2000 Fabrice Bellard
4 * Copyright (c) 2006-2010 Justin Ruggles <justin.ruggles@gmail.com>
6 * This file is part of Libav.
8 * Libav is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
13 * Libav is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with Libav; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
25 * AC-3 encoder & E-AC-3 encoder common header
28 #ifndef AVCODEC_AC3ENC_H
29 #define AVCODEC_AC3ENC_H
33 #include "libavutil/float_dsp.h"
41 #ifndef CONFIG_AC3ENC_FLOAT
42 #define CONFIG_AC3ENC_FLOAT 0
45 #define OFFSET(param) offsetof(AC3EncodeContext, options.param)
46 #define AC3ENC_PARAM (AV_OPT_FLAG_AUDIO_PARAM | AV_OPT_FLAG_ENCODING_PARAM)
48 #define AC3ENC_TYPE_AC3_FIXED 0
49 #define AC3ENC_TYPE_AC3 1
50 #define AC3ENC_TYPE_EAC3 2
52 #if CONFIG_AC3ENC_FLOAT
53 #define AC3_NAME(x) ff_ac3_float_ ## x
54 #define MAC_COEF(d,a,b) ((d)+=(a)*(b))
55 #define COEF_MIN (-16777215.0/16777216.0)
56 #define COEF_MAX ( 16777215.0/16777216.0)
57 #define NEW_CPL_COORD_THRESHOLD 0.03
58 typedef float SampleType;
59 typedef float CoefType;
60 typedef float CoefSumType;
62 #define AC3_NAME(x) ff_ac3_fixed_ ## x
63 #define MAC_COEF(d,a,b) MAC64(d,a,b)
64 #define COEF_MIN -16777215
65 #define COEF_MAX 16777215
66 #define NEW_CPL_COORD_THRESHOLD 503317
67 typedef int16_t SampleType;
68 typedef int32_t CoefType;
69 typedef int64_t CoefSumType;
72 /* common option values */
73 #define AC3ENC_OPT_NONE -1
74 #define AC3ENC_OPT_AUTO -1
75 #define AC3ENC_OPT_OFF 0
76 #define AC3ENC_OPT_ON 1
77 #define AC3ENC_OPT_NOT_INDICATED 0
78 #define AC3ENC_OPT_MODE_ON 2
79 #define AC3ENC_OPT_MODE_OFF 1
81 /* specific option values */
82 #define AC3ENC_OPT_LARGE_ROOM 1
83 #define AC3ENC_OPT_SMALL_ROOM 2
84 #define AC3ENC_OPT_DOWNMIX_LTRT 1
85 #define AC3ENC_OPT_DOWNMIX_LORO 2
86 #define AC3ENC_OPT_ADCONV_STANDARD 0
87 #define AC3ENC_OPT_ADCONV_HDCD 1
91 * Encoding Options used by AVOption.
93 typedef struct AC3EncOptions {
94 /* AC-3 metadata options*/
97 float center_mix_level;
98 float surround_mix_level;
99 int dolby_surround_mode;
100 int audio_production_info;
106 int preferred_stereo_downmix;
107 float ltrt_center_mix_level;
108 float ltrt_surround_mix_level;
109 float loro_center_mix_level;
110 float loro_surround_mix_level;
112 int dolby_surround_ex_mode;
113 int dolby_headphone_mode;
114 int ad_converter_type;
115 int eac3_mixing_metadata;
116 int eac3_info_metadata;
118 /* other encoding options */
119 int allow_per_frame_metadata;
120 int stereo_rematrixing;
121 int channel_coupling;
126 * Data for a single audio block.
128 typedef struct AC3Block {
129 CoefType **mdct_coef; ///< MDCT coefficients
130 int32_t **fixed_coef; ///< fixed-point MDCT coefficients
131 uint8_t **exp; ///< original exponents
132 uint8_t **grouped_exp; ///< grouped exponents
133 int16_t **psd; ///< psd per frequency bin
134 int16_t **band_psd; ///< psd per critical band
135 int16_t **mask; ///< masking curve
136 uint16_t **qmant; ///< quantized mantissas
137 uint8_t **cpl_coord_exp; ///< coupling coord exponents (cplcoexp)
138 uint8_t **cpl_coord_mant; ///< coupling coord mantissas (cplcomant)
139 uint8_t coeff_shift[AC3_MAX_CHANNELS]; ///< fixed-point coefficient shift values
140 uint8_t new_rematrixing_strategy; ///< send new rematrixing flags in this block
141 int num_rematrixing_bands; ///< number of rematrixing bands
142 uint8_t rematrixing_flags[4]; ///< rematrixing flags
143 int new_cpl_strategy; ///< send new coupling strategy
144 int cpl_in_use; ///< coupling in use for this block (cplinu)
145 uint8_t channel_in_cpl[AC3_MAX_CHANNELS]; ///< channel in coupling (chincpl)
146 int num_cpl_channels; ///< number of channels in coupling
147 uint8_t new_cpl_coords[AC3_MAX_CHANNELS]; ///< send new coupling coordinates (cplcoe)
148 uint8_t cpl_master_exp[AC3_MAX_CHANNELS]; ///< coupling coord master exponents (mstrcplco)
149 int new_snr_offsets; ///< send new SNR offsets
150 int new_cpl_leak; ///< send new coupling leak info
151 int end_freq[AC3_MAX_CHANNELS]; ///< end frequency bin (endmant)
155 * AC-3 encoder private context.
157 typedef struct AC3EncodeContext {
158 AVClass *av_class; ///< AVClass used for AVOption
159 AC3EncOptions options; ///< encoding options
160 AVCodecContext *avctx; ///< parent AVCodecContext
161 PutBitContext pb; ///< bitstream writer context
163 AVFloatDSPContext fdsp;
164 AC3DSPContext ac3dsp; ///< AC-3 optimized functions
165 FFTContext mdct; ///< FFT context for MDCT calculation
166 const SampleType *mdct_window; ///< MDCT window function array
168 AC3Block blocks[AC3_MAX_BLOCKS]; ///< per-block info
170 int fixed_point; ///< indicates if fixed-point encoder is being used
171 int eac3; ///< indicates if this is E-AC-3 vs. AC-3
172 int bitstream_id; ///< bitstream id (bsid)
173 int bitstream_mode; ///< bitstream mode (bsmod)
175 int bit_rate; ///< target bit rate, in bits-per-second
176 int sample_rate; ///< sampling frequency, in Hz
178 int num_blks_code; ///< number of blocks code (numblkscod)
179 int num_blocks; ///< number of blocks per frame
180 int frame_size_min; ///< minimum frame size in case rounding is necessary
181 int frame_size; ///< current frame size in bytes
182 int frame_size_code; ///< frame size code (frmsizecod)
184 int64_t bits_written; ///< bit count (used to avg. bitrate)
185 int64_t samples_written; ///< sample count (used to avg. bitrate)
187 int fbw_channels; ///< number of full-bandwidth channels (nfchans)
188 int channels; ///< total number of channels (nchans)
189 int lfe_on; ///< indicates if there is an LFE channel (lfeon)
190 int lfe_channel; ///< channel index of the LFE channel
191 int has_center; ///< indicates if there is a center channel
192 int has_surround; ///< indicates if there are one or more surround channels
193 int channel_mode; ///< channel mode (acmod)
194 const uint8_t *channel_map; ///< channel map used to reorder channels
196 int center_mix_level; ///< center mix level code
197 int surround_mix_level; ///< surround mix level code
198 int ltrt_center_mix_level; ///< Lt/Rt center mix level code
199 int ltrt_surround_mix_level; ///< Lt/Rt surround mix level code
200 int loro_center_mix_level; ///< Lo/Ro center mix level code
201 int loro_surround_mix_level; ///< Lo/Ro surround mix level code
203 int cutoff; ///< user-specified cutoff frequency, in Hz
204 int bandwidth_code; ///< bandwidth code (0 to 60) (chbwcod)
205 int start_freq[AC3_MAX_CHANNELS]; ///< start frequency bin (strtmant)
206 int cpl_end_freq; ///< coupling channel end frequency bin
208 int cpl_on; ///< coupling turned on for this frame
209 int cpl_enabled; ///< coupling enabled for all frames
210 int num_cpl_subbands; ///< number of coupling subbands (ncplsubnd)
211 int num_cpl_bands; ///< number of coupling bands (ncplbnd)
212 uint8_t cpl_band_sizes[AC3_MAX_CPL_BANDS]; ///< number of coeffs in each coupling band
214 int rematrixing_enabled; ///< stereo rematrixing enabled
216 /* bitrate allocation control */
217 int slow_gain_code; ///< slow gain code (sgaincod)
218 int slow_decay_code; ///< slow decay code (sdcycod)
219 int fast_decay_code; ///< fast decay code (fdcycod)
220 int db_per_bit_code; ///< dB/bit code (dbpbcod)
221 int floor_code; ///< floor code (floorcod)
222 AC3BitAllocParameters bit_alloc; ///< bit allocation parameters
223 int coarse_snr_offset; ///< coarse SNR offsets (csnroffst)
224 int fast_gain_code[AC3_MAX_CHANNELS]; ///< fast gain codes (signal-to-mask ratio) (fgaincod)
225 int fine_snr_offset[AC3_MAX_CHANNELS]; ///< fine SNR offsets (fsnroffst)
226 int frame_bits_fixed; ///< number of non-coefficient bits for fixed parameters
227 int frame_bits; ///< all frame bits except exponents and mantissas
228 int exponent_bits; ///< number of bits used for exponents
230 SampleType *windowed_samples;
231 SampleType **planar_samples;
233 uint8_t *bap1_buffer;
234 CoefType *mdct_coef_buffer;
235 int32_t *fixed_coef_buffer;
237 uint8_t *grouped_exp_buffer;
239 int16_t *band_psd_buffer;
240 int16_t *mask_buffer;
241 int16_t *qmant_buffer;
242 uint8_t *cpl_coord_exp_buffer;
243 uint8_t *cpl_coord_mant_buffer;
245 uint8_t exp_strategy[AC3_MAX_CHANNELS][AC3_MAX_BLOCKS]; ///< exponent strategies
246 uint8_t frame_exp_strategy[AC3_MAX_CHANNELS]; ///< frame exp strategy index
247 int use_frame_exp_strategy; ///< indicates use of frame exp strategy
248 uint8_t exp_ref_block[AC3_MAX_CHANNELS][AC3_MAX_BLOCKS]; ///< reference blocks for EXP_REUSE
249 uint8_t *ref_bap [AC3_MAX_CHANNELS][AC3_MAX_BLOCKS]; ///< bit allocation pointers (bap)
250 int ref_bap_set; ///< indicates if ref_bap pointers have been set
252 /* fixed vs. float function pointers */
253 void (*mdct_end)(struct AC3EncodeContext *s);
254 int (*mdct_init)(struct AC3EncodeContext *s);
256 /* fixed vs. float templated function pointers */
257 int (*allocate_sample_buffers)(struct AC3EncodeContext *s);
259 /* AC-3 vs. E-AC-3 function pointers */
260 void (*output_frame_header)(struct AC3EncodeContext *s);
264 extern const uint64_t ff_ac3_channel_layouts[19];
266 int ff_ac3_encode_init(AVCodecContext *avctx);
268 int ff_ac3_encode_close(AVCodecContext *avctx);
270 int ff_ac3_validate_metadata(AC3EncodeContext *s);
272 void ff_ac3_adjust_frame_size(AC3EncodeContext *s);
274 void ff_ac3_compute_coupling_strategy(AC3EncodeContext *s);
276 void ff_ac3_apply_rematrixing(AC3EncodeContext *s);
278 void ff_ac3_process_exponents(AC3EncodeContext *s);
280 int ff_ac3_compute_bit_allocation(AC3EncodeContext *s);
282 void ff_ac3_group_exponents(AC3EncodeContext *s);
284 void ff_ac3_quantize_mantissas(AC3EncodeContext *s);
286 void ff_ac3_output_frame(AC3EncodeContext *s, unsigned char *frame);
289 /* prototypes for functions in ac3enc_fixed.c and ac3enc_float.c */
291 void ff_ac3_fixed_mdct_end(AC3EncodeContext *s);
292 void ff_ac3_float_mdct_end(AC3EncodeContext *s);
294 int ff_ac3_fixed_mdct_init(AC3EncodeContext *s);
295 int ff_ac3_float_mdct_init(AC3EncodeContext *s);
298 /* prototypes for functions in ac3enc_template.c */
300 int ff_ac3_fixed_allocate_sample_buffers(AC3EncodeContext *s);
301 int ff_ac3_float_allocate_sample_buffers(AC3EncodeContext *s);
303 int ff_ac3_fixed_encode_frame(AVCodecContext *avctx, AVPacket *avpkt,
304 const AVFrame *frame, int *got_packet_ptr);
305 int ff_ac3_float_encode_frame(AVCodecContext *avctx, AVPacket *avpkt,
306 const AVFrame *frame, int *got_packet_ptr);
308 #endif /* AVCODEC_AC3ENC_H */