3 * Copyright (c) 2011 Justin Ruggles <justin.ruggles@gmail.com>
5 * This file is part of Libav.
7 * Libav 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 * Libav 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 Libav; 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
32 #define AC3ENC_TYPE AC3ENC_TYPE_EAC3
33 #include "ac3enc_opts_template.c"
34 static AVClass eac3enc_class = { "E-AC-3 Encoder", av_default_item_name,
35 eac3_options, LIBAVUTIL_VERSION_INT };
38 void ff_eac3_set_cpl_states(AC3EncodeContext *s)
41 int first_cpl_coords[AC3_MAX_CHANNELS];
43 /* set first cpl coords */
44 for (ch = 1; ch <= s->fbw_channels; ch++)
45 first_cpl_coords[ch] = 1;
46 for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {
47 AC3Block *block = &s->blocks[blk];
48 for (ch = 1; ch <= s->fbw_channels; ch++) {
49 if (block->channel_in_cpl[ch]) {
50 if (first_cpl_coords[ch]) {
51 block->new_cpl_coords = 2;
52 first_cpl_coords[ch] = 0;
55 first_cpl_coords[ch] = 1;
60 /* set first cpl leak */
61 for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {
62 AC3Block *block = &s->blocks[blk];
63 if (block->cpl_in_use) {
64 block->new_cpl_leak = 2;
71 void ff_eac3_output_frame_header(AC3EncodeContext *s)
74 AC3EncOptions *opt = &s->options;
76 put_bits(&s->pb, 16, 0x0b77); /* sync word */
79 put_bits(&s->pb, 2, 0); /* stream type = independent */
80 put_bits(&s->pb, 3, 0); /* substream id = 0 */
81 put_bits(&s->pb, 11, (s->frame_size / 2) - 1); /* frame size */
82 if (s->bit_alloc.sr_shift) {
83 put_bits(&s->pb, 2, 0x3); /* fscod2 */
84 put_bits(&s->pb, 2, s->bit_alloc.sr_code); /* sample rate code */
86 put_bits(&s->pb, 2, s->bit_alloc.sr_code); /* sample rate code */
87 put_bits(&s->pb, 2, 0x3); /* number of blocks = 6 */
89 put_bits(&s->pb, 3, s->channel_mode); /* audio coding mode */
90 put_bits(&s->pb, 1, s->lfe_on); /* LFE channel indicator */
91 put_bits(&s->pb, 5, s->bitstream_id); /* bitstream id (EAC3=16) */
92 put_bits(&s->pb, 5, -opt->dialogue_level); /* dialogue normalization level */
93 put_bits(&s->pb, 1, 0); /* no compression gain */
94 put_bits(&s->pb, 1, 0); /* no mixing metadata */
95 /* TODO: mixing metadata */
96 put_bits(&s->pb, 1, 0); /* no info metadata */
97 /* TODO: info metadata */
98 put_bits(&s->pb, 1, 0); /* no additional bit stream info */
101 put_bits(&s->pb, 1, 1); /* exponent strategy syntax = each block */
102 put_bits(&s->pb, 1, 0); /* aht enabled = no */
103 put_bits(&s->pb, 2, 0); /* snr offset strategy = 1 */
104 put_bits(&s->pb, 1, 0); /* transient pre-noise processing enabled = no */
105 put_bits(&s->pb, 1, 0); /* block switch syntax enabled = no */
106 put_bits(&s->pb, 1, 0); /* dither flag syntax enabled = no */
107 put_bits(&s->pb, 1, 0); /* bit allocation model syntax enabled = no */
108 put_bits(&s->pb, 1, 0); /* fast gain codes enabled = no */
109 put_bits(&s->pb, 1, 0); /* dba syntax enabled = no */
110 put_bits(&s->pb, 1, 0); /* skip field syntax enabled = no */
111 put_bits(&s->pb, 1, 0); /* spx enabled = no */
112 /* coupling strategy use flags */
113 if (s->channel_mode > AC3_CHMODE_MONO) {
114 put_bits(&s->pb, 1, s->blocks[0].cpl_in_use);
115 for (blk = 1; blk < AC3_MAX_BLOCKS; blk++) {
116 AC3Block *block = &s->blocks[blk];
117 put_bits(&s->pb, 1, block->new_cpl_strategy);
118 if (block->new_cpl_strategy)
119 put_bits(&s->pb, 1, block->cpl_in_use);
122 /* exponent strategy */
123 for (blk = 0; blk < AC3_MAX_BLOCKS; blk++)
124 for (ch = !s->blocks[blk].cpl_in_use; ch <= s->fbw_channels; ch++)
125 put_bits(&s->pb, 2, s->exp_strategy[ch][blk]);
127 for (blk = 0; blk < AC3_MAX_BLOCKS; blk++)
128 put_bits(&s->pb, 1, s->exp_strategy[s->lfe_channel][blk]);
130 /* E-AC-3 to AC-3 converter exponent strategy (unfortunately not optional...) */
131 for (ch = 1; ch <= s->fbw_channels; ch++)
132 put_bits(&s->pb, 5, 0);
134 put_bits(&s->pb, 6, s->coarse_snr_offset);
135 put_bits(&s->pb, 4, s->fine_snr_offset[1]);
136 /* block start info */
137 put_bits(&s->pb, 1, 0);
141 #if CONFIG_EAC3_ENCODER
142 AVCodec ff_eac3_encoder = {
144 .type = AVMEDIA_TYPE_AUDIO,
146 .priv_data_size = sizeof(AC3EncodeContext),
147 .init = ff_ac3_encode_init,
148 .encode = ff_ac3_float_encode_frame,
149 .close = ff_ac3_encode_close,
150 .sample_fmts = (const enum AVSampleFormat[]){AV_SAMPLE_FMT_FLT,AV_SAMPLE_FMT_NONE},
151 .long_name = NULL_IF_CONFIG_SMALL("ATSC A/52 E-AC-3"),
152 .priv_class = &eac3enc_class,
153 .channel_layouts = ff_ac3_channel_layouts,