yading@10: /*
yading@10:  * E-AC-3 encoder
yading@10:  * Copyright (c) 2011 Justin Ruggles <justin.ruggles@gmail.com>
yading@10:  *
yading@10:  * This file is part of Libav.
yading@10:  *
yading@10:  * Libav is free software; you can redistribute it and/or
yading@10:  * modify it under the terms of the GNU Lesser General Public
yading@10:  * License as published by the Free Software Foundation; either
yading@10:  * version 2.1 of the License, or (at your option) any later version.
yading@10:  *
yading@10:  * Libav is distributed in the hope that it will be useful,
yading@10:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@10:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@10:  * Lesser General Public License for more details.
yading@10:  *
yading@10:  * You should have received a copy of the GNU Lesser General Public
yading@10:  * License along with Libav; if not, write to the Free Software
yading@10:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@10:  */
yading@10: 
yading@10: /**
yading@10:  * @file
yading@10:  * E-AC-3 encoder
yading@10:  */
yading@10: 
yading@10: #define CONFIG_AC3ENC_FLOAT 1
yading@10: #include "ac3enc.h"
yading@10: #include "eac3enc.h"
yading@10: #include "eac3_data.h"
yading@10: 
yading@10: 
yading@10: #define AC3ENC_TYPE AC3ENC_TYPE_EAC3
yading@10: #include "ac3enc_opts_template.c"
yading@10: 
yading@10: static const AVClass eac3enc_class = {
yading@10:     .class_name = "E-AC-3 Encoder",
yading@10:     .item_name  = av_default_item_name,
yading@10:     .option     = ac3_options,
yading@10:     .version    = LIBAVUTIL_VERSION_INT,
yading@10: };
yading@10: 
yading@10: /**
yading@10:  * LUT for finding a matching frame exponent strategy index from a set of
yading@10:  * exponent strategies for a single channel across all 6 blocks.
yading@10:  */
yading@10: static int8_t eac3_frame_expstr_index_tab[3][4][4][4][4][4];
yading@10: 
yading@10: 
yading@10: void ff_eac3_exponent_init(void)
yading@10: {
yading@10:     int i;
yading@10: 
yading@10:     memset(eac3_frame_expstr_index_tab, -1, sizeof(eac3_frame_expstr_index_tab));
yading@10:     for (i = 0; i < 32; i++) {
yading@10:         eac3_frame_expstr_index_tab[ff_eac3_frm_expstr[i][0]-1]
yading@10:                                    [ff_eac3_frm_expstr[i][1]]
yading@10:                                    [ff_eac3_frm_expstr[i][2]]
yading@10:                                    [ff_eac3_frm_expstr[i][3]]
yading@10:                                    [ff_eac3_frm_expstr[i][4]]
yading@10:                                    [ff_eac3_frm_expstr[i][5]] = i;
yading@10:     }
yading@10: }
yading@10: 
yading@10: 
yading@10: void ff_eac3_get_frame_exp_strategy(AC3EncodeContext *s)
yading@10: {
yading@10:     int ch;
yading@10: 
yading@10:     if (s->num_blocks < 6) {
yading@10:         s->use_frame_exp_strategy = 0;
yading@10:         return;
yading@10:     }
yading@10: 
yading@10:     s->use_frame_exp_strategy = 1;
yading@10:     for (ch = !s->cpl_on; ch <= s->fbw_channels; ch++) {
yading@10:         int expstr = eac3_frame_expstr_index_tab[s->exp_strategy[ch][0]-1]
yading@10:                                                 [s->exp_strategy[ch][1]]
yading@10:                                                 [s->exp_strategy[ch][2]]
yading@10:                                                 [s->exp_strategy[ch][3]]
yading@10:                                                 [s->exp_strategy[ch][4]]
yading@10:                                                 [s->exp_strategy[ch][5]];
yading@10:         if (expstr < 0) {
yading@10:             s->use_frame_exp_strategy = 0;
yading@10:             break;
yading@10:         }
yading@10:         s->frame_exp_strategy[ch] = expstr;
yading@10:     }
yading@10: }
yading@10: 
yading@10: 
yading@10: 
yading@10: void ff_eac3_set_cpl_states(AC3EncodeContext *s)
yading@10: {
yading@10:     int ch, blk;
yading@10:     int first_cpl_coords[AC3_MAX_CHANNELS];
yading@10: 
yading@10:     /* set first cpl coords */
yading@10:     for (ch = 1; ch <= s->fbw_channels; ch++)
yading@10:         first_cpl_coords[ch] = 1;
yading@10:     for (blk = 0; blk < s->num_blocks; blk++) {
yading@10:         AC3Block *block = &s->blocks[blk];
yading@10:         for (ch = 1; ch <= s->fbw_channels; ch++) {
yading@10:             if (block->channel_in_cpl[ch]) {
yading@10:                 if (first_cpl_coords[ch]) {
yading@10:                     block->new_cpl_coords[ch] = 2;
yading@10:                     first_cpl_coords[ch]  = 0;
yading@10:                 }
yading@10:             } else {
yading@10:                 first_cpl_coords[ch] = 1;
yading@10:             }
yading@10:         }
yading@10:     }
yading@10: 
yading@10:     /* set first cpl leak */
yading@10:     for (blk = 0; blk < s->num_blocks; blk++) {
yading@10:         AC3Block *block = &s->blocks[blk];
yading@10:         if (block->cpl_in_use) {
yading@10:             block->new_cpl_leak = 2;
yading@10:             break;
yading@10:         }
yading@10:     }
yading@10: }
yading@10: 
yading@10: 
yading@10: void ff_eac3_output_frame_header(AC3EncodeContext *s)
yading@10: {
yading@10:     int blk, ch;
yading@10:     AC3EncOptions *opt = &s->options;
yading@10: 
yading@10:     put_bits(&s->pb, 16, 0x0b77);                   /* sync word */
yading@10: 
yading@10:     /* BSI header */
yading@10:     put_bits(&s->pb,  2, 0);                        /* stream type = independent */
yading@10:     put_bits(&s->pb,  3, 0);                        /* substream id = 0 */
yading@10:     put_bits(&s->pb, 11, (s->frame_size / 2) - 1);  /* frame size */
yading@10:     if (s->bit_alloc.sr_shift) {
yading@10:         put_bits(&s->pb, 2, 0x3);                   /* fscod2 */
yading@10:         put_bits(&s->pb, 2, s->bit_alloc.sr_code);  /* sample rate code */
yading@10:     } else {
yading@10:         put_bits(&s->pb, 2, s->bit_alloc.sr_code);  /* sample rate code */
yading@10:         put_bits(&s->pb, 2, s->num_blks_code);      /* number of blocks */
yading@10:     }
yading@10:     put_bits(&s->pb, 3, s->channel_mode);           /* audio coding mode */
yading@10:     put_bits(&s->pb, 1, s->lfe_on);                 /* LFE channel indicator */
yading@10:     put_bits(&s->pb, 5, s->bitstream_id);           /* bitstream id (EAC3=16) */
yading@10:     put_bits(&s->pb, 5, -opt->dialogue_level);      /* dialogue normalization level */
yading@10:     put_bits(&s->pb, 1, 0);                         /* no compression gain */
yading@10:     /* mixing metadata*/
yading@10:     put_bits(&s->pb, 1, opt->eac3_mixing_metadata);
yading@10:     if (opt->eac3_mixing_metadata) {
yading@10:         if (s->channel_mode > AC3_CHMODE_STEREO)
yading@10:             put_bits(&s->pb, 2, opt->preferred_stereo_downmix);
yading@10:         if (s->has_center) {
yading@10:             put_bits(&s->pb, 3, s->ltrt_center_mix_level);
yading@10:             put_bits(&s->pb, 3, s->loro_center_mix_level);
yading@10:         }
yading@10:         if (s->has_surround) {
yading@10:             put_bits(&s->pb, 3, s->ltrt_surround_mix_level);
yading@10:             put_bits(&s->pb, 3, s->loro_surround_mix_level);
yading@10:         }
yading@10:         if (s->lfe_on)
yading@10:             put_bits(&s->pb, 1, 0);
yading@10:         put_bits(&s->pb, 1, 0);                     /* no program scale */
yading@10:         put_bits(&s->pb, 1, 0);                     /* no ext program scale */
yading@10:         put_bits(&s->pb, 2, 0);                     /* no mixing parameters */
yading@10:         if (s->channel_mode < AC3_CHMODE_STEREO)
yading@10:             put_bits(&s->pb, 1, 0);                 /* no pan info */
yading@10:         put_bits(&s->pb, 1, 0);                     /* no frame mix config info */
yading@10:     }
yading@10:     /* info metadata*/
yading@10:     put_bits(&s->pb, 1, opt->eac3_info_metadata);
yading@10:     if (opt->eac3_info_metadata) {
yading@10:         put_bits(&s->pb, 3, s->bitstream_mode);
yading@10:         put_bits(&s->pb, 1, opt->copyright);
yading@10:         put_bits(&s->pb, 1, opt->original);
yading@10:         if (s->channel_mode == AC3_CHMODE_STEREO) {
yading@10:             put_bits(&s->pb, 2, opt->dolby_surround_mode);
yading@10:             put_bits(&s->pb, 2, opt->dolby_headphone_mode);
yading@10:         }
yading@10:         if (s->channel_mode >= AC3_CHMODE_2F2R)
yading@10:             put_bits(&s->pb, 2, opt->dolby_surround_ex_mode);
yading@10:         put_bits(&s->pb, 1, opt->audio_production_info);
yading@10:         if (opt->audio_production_info) {
yading@10:             put_bits(&s->pb, 5, opt->mixing_level - 80);
yading@10:             put_bits(&s->pb, 2, opt->room_type);
yading@10:             put_bits(&s->pb, 1, opt->ad_converter_type);
yading@10:         }
yading@10:         put_bits(&s->pb, 1, 0);
yading@10:     }
yading@10:     if (s->num_blocks != 6)
yading@10:         put_bits(&s->pb, 1, !(s->avctx->frame_number % 6)); /* converter sync flag */
yading@10:     put_bits(&s->pb, 1, 0);                         /* no additional bit stream info */
yading@10: 
yading@10:     /* frame header */
yading@10:     if (s->num_blocks == 6) {
yading@10:     put_bits(&s->pb, 1, !s->use_frame_exp_strategy);/* exponent strategy syntax */
yading@10:     put_bits(&s->pb, 1, 0);                         /* aht enabled = no */
yading@10:     }
yading@10:     put_bits(&s->pb, 2, 0);                         /* snr offset strategy = 1 */
yading@10:     put_bits(&s->pb, 1, 0);                         /* transient pre-noise processing enabled = no */
yading@10:     put_bits(&s->pb, 1, 0);                         /* block switch syntax enabled = no */
yading@10:     put_bits(&s->pb, 1, 0);                         /* dither flag syntax enabled = no */
yading@10:     put_bits(&s->pb, 1, 0);                         /* bit allocation model syntax enabled = no */
yading@10:     put_bits(&s->pb, 1, 0);                         /* fast gain codes enabled = no */
yading@10:     put_bits(&s->pb, 1, 0);                         /* dba syntax enabled = no */
yading@10:     put_bits(&s->pb, 1, 0);                         /* skip field syntax enabled = no */
yading@10:     put_bits(&s->pb, 1, 0);                         /* spx enabled = no */
yading@10:     /* coupling strategy use flags */
yading@10:     if (s->channel_mode > AC3_CHMODE_MONO) {
yading@10:         put_bits(&s->pb, 1, s->blocks[0].cpl_in_use);
yading@10:         for (blk = 1; blk < s->num_blocks; blk++) {
yading@10:             AC3Block *block = &s->blocks[blk];
yading@10:             put_bits(&s->pb, 1, block->new_cpl_strategy);
yading@10:             if (block->new_cpl_strategy)
yading@10:                 put_bits(&s->pb, 1, block->cpl_in_use);
yading@10:         }
yading@10:     }
yading@10:     /* exponent strategy */
yading@10:     if (s->use_frame_exp_strategy) {
yading@10:         for (ch = !s->cpl_on; ch <= s->fbw_channels; ch++)
yading@10:             put_bits(&s->pb, 5, s->frame_exp_strategy[ch]);
yading@10:     } else {
yading@10:         for (blk = 0; blk < s->num_blocks; blk++)
yading@10:             for (ch = !s->blocks[blk].cpl_in_use; ch <= s->fbw_channels; ch++)
yading@10:                 put_bits(&s->pb, 2, s->exp_strategy[ch][blk]);
yading@10:     }
yading@10:     if (s->lfe_on) {
yading@10:         for (blk = 0; blk < s->num_blocks; blk++)
yading@10:             put_bits(&s->pb, 1, s->exp_strategy[s->lfe_channel][blk]);
yading@10:     }
yading@10:     /* E-AC-3 to AC-3 converter exponent strategy (not optional when num blocks == 6) */
yading@10:     if (s->num_blocks != 6) {
yading@10:         put_bits(&s->pb, 1, 0);
yading@10:     } else {
yading@10:     for (ch = 1; ch <= s->fbw_channels; ch++) {
yading@10:         if (s->use_frame_exp_strategy)
yading@10:             put_bits(&s->pb, 5, s->frame_exp_strategy[ch]);
yading@10:         else
yading@10:             put_bits(&s->pb, 5, 0);
yading@10:     }
yading@10:     }
yading@10:     /* snr offsets */
yading@10:     put_bits(&s->pb, 6, s->coarse_snr_offset);
yading@10:     put_bits(&s->pb, 4, s->fine_snr_offset[1]);
yading@10:     /* block start info */
yading@10:     if (s->num_blocks > 1)
yading@10:         put_bits(&s->pb, 1, 0);
yading@10: }
yading@10: 
yading@10: 
yading@10: #if CONFIG_EAC3_ENCODER
yading@10: AVCodec ff_eac3_encoder = {
yading@10:     .name            = "eac3",
yading@10:     .type            = AVMEDIA_TYPE_AUDIO,
yading@10:     .id              = AV_CODEC_ID_EAC3,
yading@10:     .priv_data_size  = sizeof(AC3EncodeContext),
yading@10:     .init            = ff_ac3_encode_init,
yading@10:     .encode2         = ff_ac3_float_encode_frame,
yading@10:     .close           = ff_ac3_encode_close,
yading@10:     .sample_fmts     = (const enum AVSampleFormat[]){ AV_SAMPLE_FMT_FLTP,
yading@10:                                                       AV_SAMPLE_FMT_NONE },
yading@10:     .long_name       = NULL_IF_CONFIG_SMALL("ATSC A/52 E-AC-3"),
yading@10:     .priv_class      = &eac3enc_class,
yading@10:     .channel_layouts = ff_ac3_channel_layouts,
yading@10:     .defaults        = ac3_defaults,
yading@10: };
yading@10: #endif