3 * Copyright (c) 2011 Justin Ruggles <justin.ruggles@gmail.com>
5 * This file is part of FFmpeg.
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.
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.
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
27 #define CONFIG_AC3ENC_FLOAT 1
29 #include "libavutil/attributes.h"
32 #include "eac3_data.h"
35 #define AC3ENC_TYPE AC3ENC_TYPE_EAC3
36 #include "ac3enc_opts_template.c"
38 static const AVClass eac3enc_class
= {
39 .class_name
= "E-AC-3 Encoder",
40 .item_name
= av_default_item_name
,
41 .option
= ac3_options
,
42 .version
= LIBAVUTIL_VERSION_INT
,
46 * LUT for finding a matching frame exponent strategy index from a set of
47 * exponent strategies for a single channel across all 6 blocks.
49 static int8_t eac3_frame_expstr_index_tab
[3][4][4][4][4][4];
52 av_cold
void ff_eac3_exponent_init(void)
56 memset(eac3_frame_expstr_index_tab
, -1, sizeof(eac3_frame_expstr_index_tab
));
57 for (i
= 0; i
< 32; i
++) {
58 eac3_frame_expstr_index_tab
[ff_eac3_frm_expstr
[i
][0]-1]
59 [ff_eac3_frm_expstr
[i
][1]]
60 [ff_eac3_frm_expstr
[i
][2]]
61 [ff_eac3_frm_expstr
[i
][3]]
62 [ff_eac3_frm_expstr
[i
][4]]
63 [ff_eac3_frm_expstr
[i
][5]] = i
;
68 void ff_eac3_get_frame_exp_strategy(AC3EncodeContext
*s
)
72 if (s
->num_blocks
< 6) {
73 s
->use_frame_exp_strategy
= 0;
77 s
->use_frame_exp_strategy
= 1;
78 for (ch
= !s
->cpl_on
; ch
<= s
->fbw_channels
; ch
++) {
79 int expstr
= eac3_frame_expstr_index_tab
[s
->exp_strategy
[ch
][0]-1]
80 [s
->exp_strategy
[ch
][1]]
81 [s
->exp_strategy
[ch
][2]]
82 [s
->exp_strategy
[ch
][3]]
83 [s
->exp_strategy
[ch
][4]]
84 [s
->exp_strategy
[ch
][5]];
86 s
->use_frame_exp_strategy
= 0;
89 s
->frame_exp_strategy
[ch
] = expstr
;
95 void ff_eac3_set_cpl_states(AC3EncodeContext
*s
)
98 int first_cpl_coords
[AC3_MAX_CHANNELS
];
100 /* set first cpl coords */
101 for (ch
= 1; ch
<= s
->fbw_channels
; ch
++)
102 first_cpl_coords
[ch
] = 1;
103 for (blk
= 0; blk
< s
->num_blocks
; blk
++) {
104 AC3Block
*block
= &s
->blocks
[blk
];
105 for (ch
= 1; ch
<= s
->fbw_channels
; ch
++) {
106 if (block
->channel_in_cpl
[ch
]) {
107 if (first_cpl_coords
[ch
]) {
108 block
->new_cpl_coords
[ch
] = 2;
109 first_cpl_coords
[ch
] = 0;
112 first_cpl_coords
[ch
] = 1;
117 /* set first cpl leak */
118 for (blk
= 0; blk
< s
->num_blocks
; blk
++) {
119 AC3Block
*block
= &s
->blocks
[blk
];
120 if (block
->cpl_in_use
) {
121 block
->new_cpl_leak
= 2;
128 void ff_eac3_output_frame_header(AC3EncodeContext
*s
)
131 AC3EncOptions
*opt
= &s
->options
;
133 put_bits(&s
->pb
, 16, 0x0b77); /* sync word */
136 put_bits(&s
->pb
, 2, 0); /* stream type = independent */
137 put_bits(&s
->pb
, 3, 0); /* substream id = 0 */
138 put_bits(&s
->pb
, 11, (s
->frame_size
/ 2) - 1); /* frame size */
139 if (s
->bit_alloc
.sr_shift
) {
140 put_bits(&s
->pb
, 2, 0x3); /* fscod2 */
141 put_bits(&s
->pb
, 2, s
->bit_alloc
.sr_code
); /* sample rate code */
143 put_bits(&s
->pb
, 2, s
->bit_alloc
.sr_code
); /* sample rate code */
144 put_bits(&s
->pb
, 2, s
->num_blks_code
); /* number of blocks */
146 put_bits(&s
->pb
, 3, s
->channel_mode
); /* audio coding mode */
147 put_bits(&s
->pb
, 1, s
->lfe_on
); /* LFE channel indicator */
148 put_bits(&s
->pb
, 5, s
->bitstream_id
); /* bitstream id (EAC3=16) */
149 put_bits(&s
->pb
, 5, -opt
->dialogue_level
); /* dialogue normalization level */
150 put_bits(&s
->pb
, 1, 0); /* no compression gain */
152 put_bits(&s
->pb
, 1, opt
->eac3_mixing_metadata
);
153 if (opt
->eac3_mixing_metadata
) {
154 if (s
->channel_mode
> AC3_CHMODE_STEREO
)
155 put_bits(&s
->pb
, 2, opt
->preferred_stereo_downmix
);
157 put_bits(&s
->pb
, 3, s
->ltrt_center_mix_level
);
158 put_bits(&s
->pb
, 3, s
->loro_center_mix_level
);
160 if (s
->has_surround
) {
161 put_bits(&s
->pb
, 3, s
->ltrt_surround_mix_level
);
162 put_bits(&s
->pb
, 3, s
->loro_surround_mix_level
);
165 put_bits(&s
->pb
, 1, 0);
166 put_bits(&s
->pb
, 1, 0); /* no program scale */
167 put_bits(&s
->pb
, 1, 0); /* no ext program scale */
168 put_bits(&s
->pb
, 2, 0); /* no mixing parameters */
169 if (s
->channel_mode
< AC3_CHMODE_STEREO
)
170 put_bits(&s
->pb
, 1, 0); /* no pan info */
171 put_bits(&s
->pb
, 1, 0); /* no frame mix config info */
174 put_bits(&s
->pb
, 1, opt
->eac3_info_metadata
);
175 if (opt
->eac3_info_metadata
) {
176 put_bits(&s
->pb
, 3, s
->bitstream_mode
);
177 put_bits(&s
->pb
, 1, opt
->copyright
);
178 put_bits(&s
->pb
, 1, opt
->original
);
179 if (s
->channel_mode
== AC3_CHMODE_STEREO
) {
180 put_bits(&s
->pb
, 2, opt
->dolby_surround_mode
);
181 put_bits(&s
->pb
, 2, opt
->dolby_headphone_mode
);
183 if (s
->channel_mode
>= AC3_CHMODE_2F2R
)
184 put_bits(&s
->pb
, 2, opt
->dolby_surround_ex_mode
);
185 put_bits(&s
->pb
, 1, opt
->audio_production_info
);
186 if (opt
->audio_production_info
) {
187 put_bits(&s
->pb
, 5, opt
->mixing_level
- 80);
188 put_bits(&s
->pb
, 2, opt
->room_type
);
189 put_bits(&s
->pb
, 1, opt
->ad_converter_type
);
191 put_bits(&s
->pb
, 1, 0);
193 if (s
->num_blocks
!= 6)
194 put_bits(&s
->pb
, 1, !(s
->avctx
->frame_number
% 6)); /* converter sync flag */
195 put_bits(&s
->pb
, 1, 0); /* no additional bit stream info */
198 if (s
->num_blocks
== 6) {
199 put_bits(&s
->pb
, 1, !s
->use_frame_exp_strategy
);/* exponent strategy syntax */
200 put_bits(&s
->pb
, 1, 0); /* aht enabled = no */
202 put_bits(&s
->pb
, 2, 0); /* snr offset strategy = 1 */
203 put_bits(&s
->pb
, 1, 0); /* transient pre-noise processing enabled = no */
204 put_bits(&s
->pb
, 1, 0); /* block switch syntax enabled = no */
205 put_bits(&s
->pb
, 1, 0); /* dither flag syntax enabled = no */
206 put_bits(&s
->pb
, 1, 0); /* bit allocation model syntax enabled = no */
207 put_bits(&s
->pb
, 1, 0); /* fast gain codes enabled = no */
208 put_bits(&s
->pb
, 1, 0); /* dba syntax enabled = no */
209 put_bits(&s
->pb
, 1, 0); /* skip field syntax enabled = no */
210 put_bits(&s
->pb
, 1, 0); /* spx enabled = no */
211 /* coupling strategy use flags */
212 if (s
->channel_mode
> AC3_CHMODE_MONO
) {
213 put_bits(&s
->pb
, 1, s
->blocks
[0].cpl_in_use
);
214 for (blk
= 1; blk
< s
->num_blocks
; blk
++) {
215 AC3Block
*block
= &s
->blocks
[blk
];
216 put_bits(&s
->pb
, 1, block
->new_cpl_strategy
);
217 if (block
->new_cpl_strategy
)
218 put_bits(&s
->pb
, 1, block
->cpl_in_use
);
221 /* exponent strategy */
222 if (s
->use_frame_exp_strategy
) {
223 for (ch
= !s
->cpl_on
; ch
<= s
->fbw_channels
; ch
++)
224 put_bits(&s
->pb
, 5, s
->frame_exp_strategy
[ch
]);
226 for (blk
= 0; blk
< s
->num_blocks
; blk
++)
227 for (ch
= !s
->blocks
[blk
].cpl_in_use
; ch
<= s
->fbw_channels
; ch
++)
228 put_bits(&s
->pb
, 2, s
->exp_strategy
[ch
][blk
]);
231 for (blk
= 0; blk
< s
->num_blocks
; blk
++)
232 put_bits(&s
->pb
, 1, s
->exp_strategy
[s
->lfe_channel
][blk
]);
234 /* E-AC-3 to AC-3 converter exponent strategy (not optional when num blocks == 6) */
235 if (s
->num_blocks
!= 6) {
236 put_bits(&s
->pb
, 1, 0);
238 for (ch
= 1; ch
<= s
->fbw_channels
; ch
++) {
239 if (s
->use_frame_exp_strategy
)
240 put_bits(&s
->pb
, 5, s
->frame_exp_strategy
[ch
]);
242 put_bits(&s
->pb
, 5, 0);
246 put_bits(&s
->pb
, 6, s
->coarse_snr_offset
);
247 put_bits(&s
->pb
, 4, s
->fine_snr_offset
[1]);
248 /* block start info */
249 if (s
->num_blocks
> 1)
250 put_bits(&s
->pb
, 1, 0);
254 AVCodec ff_eac3_encoder
= {
256 .long_name
= NULL_IF_CONFIG_SMALL("ATSC A/52 E-AC-3"),
257 .type
= AVMEDIA_TYPE_AUDIO
,
258 .id
= AV_CODEC_ID_EAC3
,
259 .priv_data_size
= sizeof(AC3EncodeContext
),
260 .init
= ff_ac3_float_encode_init
,
261 .encode2
= ff_ac3_float_encode_frame
,
262 .close
= ff_ac3_encode_close
,
263 .sample_fmts
= (const enum AVSampleFormat
[]){ AV_SAMPLE_FMT_FLTP
,
264 AV_SAMPLE_FMT_NONE
},
265 .priv_class
= &eac3enc_class
,
266 .channel_layouts
= ff_ac3_channel_layouts
,
267 .defaults
= ac3_defaults
,