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
39 #ifndef CONFIG_AC3ENC_FLOAT
40 #define CONFIG_AC3ENC_FLOAT 0
43 #define OFFSET(param) offsetof(AC3EncodeContext, options.param)
44 #define AC3ENC_PARAM (AV_OPT_FLAG_AUDIO_PARAM | AV_OPT_FLAG_ENCODING_PARAM)
46 #define AC3ENC_TYPE_AC3_FIXED 0
47 #define AC3ENC_TYPE_AC3 1
48 #define AC3ENC_TYPE_EAC3 2
50 #if CONFIG_AC3ENC_FLOAT
51 #define AC3_NAME(x) ff_ac3_float_ ## x
52 #define MAC_COEF(d,a,b) ((d)+=(a)*(b))
53 #define COEF_MIN (-16777215.0/16777216.0)
54 #define COEF_MAX ( 16777215.0/16777216.0)
55 #define NEW_CPL_COORD_THRESHOLD 0.03
56 typedef float SampleType;
57 typedef float CoefType;
58 typedef float CoefSumType;
60 #define AC3_NAME(x) ff_ac3_fixed_ ## x
61 #define MAC_COEF(d,a,b) MAC64(d,a,b)
62 #define COEF_MIN -16777215
63 #define COEF_MAX 16777215
64 #define NEW_CPL_COORD_THRESHOLD 503317
65 typedef int16_t SampleType;
66 typedef int32_t CoefType;
67 typedef int64_t CoefSumType;
70 /* common option values */
71 #define AC3ENC_OPT_NONE -1
72 #define AC3ENC_OPT_AUTO -1
73 #define AC3ENC_OPT_OFF 0
74 #define AC3ENC_OPT_ON 1
75 #define AC3ENC_OPT_NOT_INDICATED 0
76 #define AC3ENC_OPT_MODE_ON 2
77 #define AC3ENC_OPT_MODE_OFF 1
79 /* specific option values */
80 #define AC3ENC_OPT_LARGE_ROOM 1
81 #define AC3ENC_OPT_SMALL_ROOM 2
82 #define AC3ENC_OPT_DOWNMIX_LTRT 1
83 #define AC3ENC_OPT_DOWNMIX_LORO 2
84 #define AC3ENC_OPT_ADCONV_STANDARD 0
85 #define AC3ENC_OPT_ADCONV_HDCD 1
89 * Encoding Options used by AVOption.
91 typedef struct AC3EncOptions {
92 /* AC-3 metadata options*/
95 float center_mix_level;
96 float surround_mix_level;
97 int dolby_surround_mode;
98 int audio_production_info;
104 int preferred_stereo_downmix;
105 float ltrt_center_mix_level;
106 float ltrt_surround_mix_level;
107 float loro_center_mix_level;
108 float loro_surround_mix_level;
110 int dolby_surround_ex_mode;
111 int dolby_headphone_mode;
112 int ad_converter_type;
113 int eac3_mixing_metadata;
114 int eac3_info_metadata;
116 /* other encoding options */
117 int allow_per_frame_metadata;
118 int stereo_rematrixing;
119 int channel_coupling;
124 * Data for a single audio block.
126 typedef struct AC3Block {
127 CoefType **mdct_coef; ///< MDCT coefficients
128 int32_t **fixed_coef; ///< fixed-point MDCT coefficients
129 uint8_t **exp; ///< original exponents
130 uint8_t **grouped_exp; ///< grouped exponents
131 int16_t **psd; ///< psd per frequency bin
132 int16_t **band_psd; ///< psd per critical band
133 int16_t **mask; ///< masking curve
134 uint16_t **qmant; ///< quantized mantissas
135 uint8_t **cpl_coord_exp; ///< coupling coord exponents (cplcoexp)
136 uint8_t **cpl_coord_mant; ///< coupling coord mantissas (cplcomant)
137 uint8_t coeff_shift[AC3_MAX_CHANNELS]; ///< fixed-point coefficient shift values
138 uint8_t new_rematrixing_strategy; ///< send new rematrixing flags in this block
139 int num_rematrixing_bands; ///< number of rematrixing bands
140 uint8_t rematrixing_flags[4]; ///< rematrixing flags
141 int new_cpl_strategy; ///< send new coupling strategy
142 int cpl_in_use; ///< coupling in use for this block (cplinu)
143 uint8_t channel_in_cpl[AC3_MAX_CHANNELS]; ///< channel in coupling (chincpl)
144 int num_cpl_channels; ///< number of channels in coupling
145 uint8_t new_cpl_coords[AC3_MAX_CHANNELS]; ///< send new coupling coordinates (cplcoe)
146 uint8_t cpl_master_exp[AC3_MAX_CHANNELS]; ///< coupling coord master exponents (mstrcplco)
147 int new_snr_offsets; ///< send new SNR offsets
148 int new_cpl_leak; ///< send new coupling leak info
149 int end_freq[AC3_MAX_CHANNELS]; ///< end frequency bin (endmant)
153 * AC-3 encoder private context.
155 typedef struct AC3EncodeContext {
156 AVClass *av_class; ///< AVClass used for AVOption
157 AC3EncOptions options; ///< encoding options
158 AVCodecContext *avctx; ///< parent AVCodecContext
159 PutBitContext pb; ///< bitstream writer context
161 AC3DSPContext ac3dsp; ///< AC-3 optimized functions
162 FFTContext mdct; ///< FFT context for MDCT calculation
163 const SampleType *mdct_window; ///< MDCT window function array
165 AC3Block blocks[AC3_MAX_BLOCKS]; ///< per-block info
167 int fixed_point; ///< indicates if fixed-point encoder is being used
168 int eac3; ///< indicates if this is E-AC-3 vs. AC-3
169 int bitstream_id; ///< bitstream id (bsid)
170 int bitstream_mode; ///< bitstream mode (bsmod)
172 int bit_rate; ///< target bit rate, in bits-per-second
173 int sample_rate; ///< sampling frequency, in Hz
175 int num_blks_code; ///< number of blocks code (numblkscod)
176 int num_blocks; ///< number of blocks per frame
177 int frame_size_min; ///< minimum frame size in case rounding is necessary
178 int frame_size; ///< current frame size in bytes
179 int frame_size_code; ///< frame size code (frmsizecod)
181 int64_t bits_written; ///< bit count (used to avg. bitrate)
182 int64_t samples_written; ///< sample count (used to avg. bitrate)
184 int fbw_channels; ///< number of full-bandwidth channels (nfchans)
185 int channels; ///< total number of channels (nchans)
186 int lfe_on; ///< indicates if there is an LFE channel (lfeon)
187 int lfe_channel; ///< channel index of the LFE channel
188 int has_center; ///< indicates if there is a center channel
189 int has_surround; ///< indicates if there are one or more surround channels
190 int channel_mode; ///< channel mode (acmod)
191 const uint8_t *channel_map; ///< channel map used to reorder channels
193 int center_mix_level; ///< center mix level code
194 int surround_mix_level; ///< surround mix level code
195 int ltrt_center_mix_level; ///< Lt/Rt center mix level code
196 int ltrt_surround_mix_level; ///< Lt/Rt surround mix level code
197 int loro_center_mix_level; ///< Lo/Ro center mix level code
198 int loro_surround_mix_level; ///< Lo/Ro surround mix level code
200 int cutoff; ///< user-specified cutoff frequency, in Hz
201 int bandwidth_code; ///< bandwidth code (0 to 60) (chbwcod)
202 int start_freq[AC3_MAX_CHANNELS]; ///< start frequency bin (strtmant)
203 int cpl_end_freq; ///< coupling channel end frequency bin
205 int cpl_on; ///< coupling turned on for this frame
206 int cpl_enabled; ///< coupling enabled for all frames
207 int num_cpl_subbands; ///< number of coupling subbands (ncplsubnd)
208 int num_cpl_bands; ///< number of coupling bands (ncplbnd)
209 uint8_t cpl_band_sizes[AC3_MAX_CPL_BANDS]; ///< number of coeffs in each coupling band
211 int rematrixing_enabled; ///< stereo rematrixing enabled
213 /* bitrate allocation control */
214 int slow_gain_code; ///< slow gain code (sgaincod)
215 int slow_decay_code; ///< slow decay code (sdcycod)
216 int fast_decay_code; ///< fast decay code (fdcycod)
217 int db_per_bit_code; ///< dB/bit code (dbpbcod)
218 int floor_code; ///< floor code (floorcod)
219 AC3BitAllocParameters bit_alloc; ///< bit allocation parameters
220 int coarse_snr_offset; ///< coarse SNR offsets (csnroffst)
221 int fast_gain_code[AC3_MAX_CHANNELS]; ///< fast gain codes (signal-to-mask ratio) (fgaincod)
222 int fine_snr_offset[AC3_MAX_CHANNELS]; ///< fine SNR offsets (fsnroffst)
223 int frame_bits_fixed; ///< number of non-coefficient bits for fixed parameters
224 int frame_bits; ///< all frame bits except exponents and mantissas
225 int exponent_bits; ///< number of bits used for exponents
227 SampleType *windowed_samples;
228 SampleType **planar_samples;
230 uint8_t *bap1_buffer;
231 CoefType *mdct_coef_buffer;
232 int32_t *fixed_coef_buffer;
234 uint8_t *grouped_exp_buffer;
236 int16_t *band_psd_buffer;
237 int16_t *mask_buffer;
238 int16_t *qmant_buffer;
239 uint8_t *cpl_coord_exp_buffer;
240 uint8_t *cpl_coord_mant_buffer;
242 uint8_t exp_strategy[AC3_MAX_CHANNELS][AC3_MAX_BLOCKS]; ///< exponent strategies
243 uint8_t frame_exp_strategy[AC3_MAX_CHANNELS]; ///< frame exp strategy index
244 int use_frame_exp_strategy; ///< indicates use of frame exp strategy
245 uint8_t exp_ref_block[AC3_MAX_CHANNELS][AC3_MAX_BLOCKS]; ///< reference blocks for EXP_REUSE
246 uint8_t *ref_bap [AC3_MAX_CHANNELS][AC3_MAX_BLOCKS]; ///< bit allocation pointers (bap)
247 int ref_bap_set; ///< indicates if ref_bap pointers have been set
249 /* fixed vs. float function pointers */
250 void (*mdct_end)(struct AC3EncodeContext *s);
251 int (*mdct_init)(struct AC3EncodeContext *s);
253 /* fixed vs. float templated function pointers */
254 int (*allocate_sample_buffers)(struct AC3EncodeContext *s);
256 /* AC-3 vs. E-AC-3 function pointers */
257 void (*output_frame_header)(struct AC3EncodeContext *s);
261 extern const uint64_t ff_ac3_channel_layouts[19];
263 int ff_ac3_encode_init(AVCodecContext *avctx);
265 int ff_ac3_encode_close(AVCodecContext *avctx);
267 int ff_ac3_validate_metadata(AC3EncodeContext *s);
269 void ff_ac3_adjust_frame_size(AC3EncodeContext *s);
271 void ff_ac3_compute_coupling_strategy(AC3EncodeContext *s);
273 void ff_ac3_apply_rematrixing(AC3EncodeContext *s);
275 void ff_ac3_process_exponents(AC3EncodeContext *s);
277 int ff_ac3_compute_bit_allocation(AC3EncodeContext *s);
279 void ff_ac3_group_exponents(AC3EncodeContext *s);
281 void ff_ac3_quantize_mantissas(AC3EncodeContext *s);
283 void ff_ac3_output_frame(AC3EncodeContext *s, unsigned char *frame);
286 /* prototypes for functions in ac3enc_fixed.c and ac3enc_float.c */
288 void ff_ac3_fixed_mdct_end(AC3EncodeContext *s);
289 void ff_ac3_float_mdct_end(AC3EncodeContext *s);
291 int ff_ac3_fixed_mdct_init(AC3EncodeContext *s);
292 int ff_ac3_float_mdct_init(AC3EncodeContext *s);
295 /* prototypes for functions in ac3enc_template.c */
297 int ff_ac3_fixed_allocate_sample_buffers(AC3EncodeContext *s);
298 int ff_ac3_float_allocate_sample_buffers(AC3EncodeContext *s);
300 int ff_ac3_fixed_encode_frame(AVCodecContext *avctx, AVPacket *avpkt,
301 const AVFrame *frame, int *got_packet_ptr);
302 int ff_ac3_float_encode_frame(AVCodecContext *avctx, AVPacket *avpkt,
303 const AVFrame *frame, int *got_packet_ptr);
305 #endif /* AVCODEC_AC3ENC_H */