libavcodec/libtwolame.c

   1 /*
   2  * Interface to libtwolame for mp2 encoding
   3  * Copyright (c) 2012 Paul B Mahol
   4  *
   5  * This file is part of FFmpeg.
   6  *
   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.
  11  *
  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.
  16  *
  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
  20  */
  21
  22 /**
  23  * @file
  24  * Interface to libtwolame for mp2 encoding.
  25  */
  26
  27 #include <twolame.h>
  28
  29 #include "libavutil/channel_layout.h"
  30 #include "libavutil/common.h"
  31 #include "libavutil/opt.h"
  32
  33 #include "avcodec.h"
  34 #include "codec_internal.h"
  35 #include "encode.h"
  36 #include "mpegaudio.h"
  37
  38 typedef struct TWOLAMEContext {
  39     AVClass *class;
  40     int mode;
  41     int psymodel;
  42     int energy;
  43     int error_protection;
  44     int copyright;
  45     int original;
  46     int verbosity;
  47
  48     twolame_options *glopts;
  49     int64_t next_pts;
  50 } TWOLAMEContext;
  51
  52 static av_cold int twolame_encode_close(AVCodecContext *avctx)
  53 {
  54     TWOLAMEContext *s = avctx->priv_data;
  55     twolame_close(&s->glopts);
  56     return 0;
  57 }
  58
  59 static av_cold int twolame_encode_init(AVCodecContext *avctx)
  60 {
  61     TWOLAMEContext *s = avctx->priv_data;
  62     int ret;
  63
  64     avctx->frame_size = TWOLAME_SAMPLES_PER_FRAME;
  65     avctx->initial_padding = 512 - 32 + 1;
  66
  67     s->glopts = twolame_init();
  68     if (!s->glopts)
  69         return AVERROR(ENOMEM);
  70
  71     twolame_set_verbosity(s->glopts, s->verbosity);
  72     twolame_set_mode(s->glopts, s->mode);
  73     twolame_set_psymodel(s->glopts, s->psymodel);
  74     twolame_set_energy_levels(s->glopts, s->energy);
  75     twolame_set_error_protection(s->glopts, s->error_protection);
  76     twolame_set_copyright(s->glopts, s->copyright);
  77     twolame_set_original(s->glopts, s->original);
  78
  79     twolame_set_num_channels(s->glopts, avctx->ch_layout.nb_channels);
  80     twolame_set_in_samplerate(s->glopts, avctx->sample_rate);
  81     twolame_set_out_samplerate(s->glopts, avctx->sample_rate);
  82
  83     if (!avctx->bit_rate) {
  84         if ((s->mode == TWOLAME_AUTO_MODE && avctx->ch_layout.nb_channels == 1) || s->mode == TWOLAME_MONO)
  85             avctx->bit_rate = avctx->sample_rate < 28000 ? 80000 : 192000;
  86         else
  87             avctx->bit_rate = avctx->sample_rate < 28000 ? 160000 : 384000;
  88     }
  89
  90     if (avctx->flags & AV_CODEC_FLAG_QSCALE || !avctx->bit_rate) {
  91         twolame_set_VBR(s->glopts, TRUE);
  92         twolame_set_VBR_level(s->glopts,
  93                               avctx->global_quality / (float) FF_QP2LAMBDA);
  94         av_log(avctx, AV_LOG_WARNING,
  95                "VBR in MP2 is a hack, use another codec that supports it.\n");
  96     } else {
  97         twolame_set_bitrate(s->glopts, avctx->bit_rate / 1000);
  98     }
  99
 100     ret = twolame_init_params(s->glopts);
 101     if (ret) {
 102         twolame_encode_close(avctx);
 103         return AVERROR_UNKNOWN;
 104     }
 105
 106     return 0;
 107 }
 108
 109 static int twolame_encode_frame(AVCodecContext *avctx, AVPacket *avpkt,
 110                                 const AVFrame *frame, int *got_packet_ptr)
 111 {
 112     TWOLAMEContext *s = avctx->priv_data;
 113     int ret;
 114
 115     if ((ret = ff_alloc_packet(avctx, avpkt, MPA_MAX_CODED_FRAME_SIZE)) < 0)
 116         return ret;
 117
 118     if (frame) {
 119         switch (avctx->sample_fmt) {
 120         case AV_SAMPLE_FMT_FLT:
 121             ret = twolame_encode_buffer_float32_interleaved(s->glopts,
 122                                                             (const float *)frame->data[0],
 123                                                             frame->nb_samples,
 124                                                             avpkt->data,
 125                                                             avpkt->size);
 126             break;
 127         case AV_SAMPLE_FMT_FLTP:
 128             ret = twolame_encode_buffer_float32(s->glopts,
 129                                                 (const float *)frame->data[0],
 130                                                 (const float *)frame->data[1],
 131                                                 frame->nb_samples,
 132                                                 avpkt->data, avpkt->size);
 133             break;
 134         case AV_SAMPLE_FMT_S16:
 135             ret = twolame_encode_buffer_interleaved(s->glopts,
 136                                                     (const short int *)frame->data[0],
 137                                                     frame->nb_samples,
 138                                                     avpkt->data, avpkt->size);
 139             break;
 140         case AV_SAMPLE_FMT_S16P:
 141             ret = twolame_encode_buffer(s->glopts,
 142                                         (const short int *)frame->data[0],
 143                                         (const short int *)frame->data[1],
 144                                         frame->nb_samples,
 145                                         avpkt->data, avpkt->size);
 146             break;
 147         default:
 148             av_log(avctx, AV_LOG_ERROR,
 149                    "Unsupported sample format %d.\n", avctx->sample_fmt);
 150             return AVERROR_BUG;
 151         }
 152     } else {
 153         ret = twolame_encode_flush(s->glopts, avpkt->data, avpkt->size);
 154     }
 155
 156     if (!ret)     // no bytes written
 157         return 0;
 158     if (ret < 0)  // twolame error
 159         return AVERROR_UNKNOWN;
 160
 161     if (frame) {
 162         avpkt->duration = ff_samples_to_time_base(avctx, frame->nb_samples);
 163         if (frame->pts != AV_NOPTS_VALUE)
 164             avpkt->pts = frame->pts - ff_samples_to_time_base(avctx, avctx->initial_padding);
 165     } else {
 166         avpkt->pts = s->next_pts;
 167     }
 168     // this is for setting pts for flushed packet(s).
 169     if (avpkt->pts != AV_NOPTS_VALUE)
 170         s->next_pts = avpkt->pts + avpkt->duration;
 171
 172     av_shrink_packet(avpkt, ret);
 173     *got_packet_ptr = 1;
 174     return 0;
 175 }
 176
 177 #define OFFSET(x) offsetof(TWOLAMEContext, x)
 178 #define AE AV_OPT_FLAG_AUDIO_PARAM | AV_OPT_FLAG_ENCODING_PARAM
 179 static const AVOption options[] = {
 180     { "mode", "Mpeg Mode", OFFSET(mode), AV_OPT_TYPE_INT, { .i64 = TWOLAME_AUTO_MODE }, TWOLAME_AUTO_MODE, TWOLAME_MONO, AE, .unit = "mode"},
 181         { "auto", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = TWOLAME_AUTO_MODE }, 0, 0, AE, .unit = "mode" },
 182         { "stereo", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = TWOLAME_STEREO }, 0, 0, AE, .unit = "mode" },
 183         { "joint_stereo", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = TWOLAME_JOINT_STEREO }, 0, 0, AE, .unit = "mode" },
 184         { "dual_channel", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = TWOLAME_DUAL_CHANNEL }, 0, 0, AE, .unit = "mode" },
 185         { "mono", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = TWOLAME_MONO }, 0, 0, AE, .unit = "mode" },
 186     { "psymodel", "Psychoacoustic Model", OFFSET(psymodel), AV_OPT_TYPE_INT, { .i64 = 3 }, -1, 4, AE},
 187     { "energy_levels","enable energy levels", OFFSET(energy), AV_OPT_TYPE_INT, { .i64 = 0 },  0, 1, AE},
 188     { "error_protection","enable CRC error protection", OFFSET(error_protection), AV_OPT_TYPE_INT, { .i64 = 0 },  0, 1, AE},
 189     { "copyright", "set MPEG Audio Copyright flag", OFFSET(copyright), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, AE},
 190     { "original", "set MPEG Audio Original flag", OFFSET(original), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, AE},
 191     { "verbosity", "set library optput level (0-10)", OFFSET(verbosity), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 10, AE},
 192     { NULL },
 193 };
 194
 195 static const AVClass twolame_class = {
 196     .class_name = "libtwolame encoder",
 197     .item_name  = av_default_item_name,
 198     .option     = options,
 199     .version    = LIBAVUTIL_VERSION_INT,
 200 };
 201
 202 static const FFCodecDefault twolame_defaults[] = {
 203     { "b", "0" },
 204     { NULL },
 205 };
 206
 207 static const int twolame_samplerates[] = {
 208     16000, 22050, 24000, 32000, 44100, 48000, 0
 209 };
 210
 211 const FFCodec ff_libtwolame_encoder = {
 212     .p.name         = "libtwolame",
 213     CODEC_LONG_NAME("libtwolame MP2 (MPEG audio layer 2)"),
 214     .p.type         = AVMEDIA_TYPE_AUDIO,
 215     .p.id           = AV_CODEC_ID_MP2,
 216     .p.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_DELAY,
 217     .caps_internal  = FF_CODEC_CAP_NOT_INIT_THREADSAFE,
 218     .priv_data_size = sizeof(TWOLAMEContext),
 219     .init           = twolame_encode_init,
 220     FF_CODEC_ENCODE_CB(twolame_encode_frame),
 221     .close          = twolame_encode_close,
 222     .defaults       = twolame_defaults,
 223     .p.priv_class   = &twolame_class,
 224     .p.sample_fmts  = (const enum AVSampleFormat[]) {
 225         AV_SAMPLE_FMT_FLT,
 226         AV_SAMPLE_FMT_FLTP,
 227         AV_SAMPLE_FMT_S16,
 228         AV_SAMPLE_FMT_S16P,
 229         AV_SAMPLE_FMT_NONE
 230     },
 231     .p.ch_layouts    = (const AVChannelLayout[]) {
 232         AV_CHANNEL_LAYOUT_MONO,
 233         AV_CHANNEL_LAYOUT_STEREO,
 234         { 0 },
 235     },
 236     .p.supported_samplerates = twolame_samplerates,
 237     .p.wrapper_name = "libtwolame",
 238 };