FFmpeg: libavcodec/libtwolame.c Source File

FFmpeg
libtwolame.c
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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/opt.h"
30 #include "avcodec.h"
31 #include "internal.h"
32 #include "mpegaudio.h"
33 
34  typedef struct TWOLAMEContext {
35   AVClass *class;
36   int mode;
37   int psymodel;
38   int energy;
39   int error_protection;
40   int copyright;
41   int original;
42 
43   twolame_options *glopts;
44   int64_t next_pts;
45 } TWOLAMEContext;
46 
47  static av_cold int twolame_encode_close(AVCodecContext *avctx)
48 {
49  TWOLAMEContext *s = avctx->priv_data;
50  twolame_close(&s->glopts);
51  return 0;
52 }
53 
54  static av_cold int twolame_encode_init(AVCodecContext *avctx)
55 {
56  TWOLAMEContext *s = avctx->priv_data;
57  int ret;
58 
59  avctx->frame_size = TWOLAME_SAMPLES_PER_FRAME;
60 
61  s->glopts = twolame_init();
62  if (!s->glopts)
63  return AVERROR(ENOMEM);
64 
65  twolame_set_verbosity(s->glopts, 0);
66  twolame_set_mode(s->glopts, s->mode);
67  twolame_set_psymodel(s->glopts, s->psymodel);
68  twolame_set_energy_levels(s->glopts, s->energy);
69  twolame_set_error_protection(s->glopts, s->error_protection);
70  twolame_set_copyright(s->glopts, s->copyright);
71  twolame_set_original(s->glopts, s->original);
72 
73  twolame_set_num_channels(s->glopts, avctx->channels);
74  twolame_set_in_samplerate(s->glopts, avctx->sample_rate);
75  twolame_set_out_samplerate(s->glopts, avctx->sample_rate);
76  if (avctx->flags & CODEC_FLAG_QSCALE || !avctx->bit_rate) {
77  twolame_set_VBR(s->glopts, TRUE);
78  twolame_set_VBR_level(s->glopts, avctx->global_quality);
79  av_log(avctx, AV_LOG_WARNING, "VBR mode is experimental!\n");
80  } else {
81  twolame_set_bitrate(s->glopts, avctx->bit_rate / 1000);
82  }
83 
84  if ((ret = twolame_init_params(s->glopts)))
85  goto error;
86 
87  return 0;
88 error:
89  twolame_encode_close(avctx);
90  return ret;
91 }
92 
93  static int twolame_encode_frame(AVCodecContext *avctx, AVPacket *avpkt,
94  const AVFrame *frame, int *got_packet_ptr)
95 {
96  TWOLAMEContext *s = avctx->priv_data;
97  int ret;
98 
99  if ((ret = ff_alloc_packet2(avctx, avpkt, MPA_MAX_CODED_FRAME_SIZE)) < 0)
100  return ret;
101 
102  if (frame) {
103  switch (avctx->sample_fmt) {
104  case AV_SAMPLE_FMT_FLT:
105  ret = twolame_encode_buffer_float32_interleaved(s->glopts,
106  frame->data[0],
107  frame->nb_samples,
108  avpkt->data, avpkt->size);
109  break;
110  case AV_SAMPLE_FMT_FLTP:
111  ret = twolame_encode_buffer_float32(s->glopts,
112  frame->data[0], frame->data[1],
113  frame->nb_samples,
114  avpkt->data, avpkt->size);
115  break;
116  case AV_SAMPLE_FMT_S16:
117  ret = twolame_encode_buffer_interleaved(s->glopts,
118  frame->data[0],
119  frame->nb_samples,
120  avpkt->data, avpkt->size);
121  break;
122  case AV_SAMPLE_FMT_S16P:
123  ret = twolame_encode_buffer(s->glopts,
124  frame->data[0], frame->data[1],
125  frame->nb_samples,
126  avpkt->data, avpkt->size);
127  break;
128  default:
129  return AVERROR_BUG;
130  }
131  } else {
132  ret = twolame_encode_flush(s->glopts, avpkt->data, avpkt->size);
133  }
134 
135  if (ret > 0) {
136  avpkt->duration = ff_samples_to_time_base(avctx, avctx->frame_size);
137  if (frame) {
138  if (frame->pts != AV_NOPTS_VALUE)
139  avpkt->pts = frame->pts;
140  } else {
141  avpkt->pts = s->next_pts;
142  }
143  if (avpkt->pts != AV_NOPTS_VALUE)
144  s->next_pts = avpkt->pts + avpkt->duration;
145 
146  avpkt->size = ret;
147  *got_packet_ptr = 1;
148  return 0;
149  }
150 
151  return ret;
152 }
153 
154  #define OFFSET(x) offsetof(TWOLAMEContext, x)
155  #define AE AV_OPT_FLAG_AUDIO_PARAM | AV_OPT_FLAG_ENCODING_PARAM
156  static const AVOption options[] = {
157  { "mode", "Mpeg Mode", OFFSET(mode), AV_OPT_TYPE_INT, { .i64 = TWOLAME_AUTO_MODE }, TWOLAME_AUTO_MODE, TWOLAME_MONO, AE, "mode"},
158  { "auto", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = TWOLAME_AUTO_MODE }, 0, 0, AE, "mode" },
159  { "stereo", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = TWOLAME_STEREO }, 0, 0, AE, "mode" },
160  { "joint_stereo", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = TWOLAME_JOINT_STEREO }, 0, 0, AE, "mode" },
161  { "dual_channel", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = TWOLAME_DUAL_CHANNEL }, 0, 0, AE, "mode" },
162  { "mono", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = TWOLAME_MONO }, 0, 0, AE, "mode" },
163  { "psymodel", "Psychoacoustic Model", OFFSET(psymodel), AV_OPT_TYPE_INT, { .i64 = 3 }, -1, 4, AE},
164  { "energy_levels","enable energy levels", OFFSET(energy), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, AE},
165  { "error_protection","enable CRC error protection", OFFSET(error_protection), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, AE},
166  { "copyright", "set MPEG Audio Copyright flag", OFFSET(copyright), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, AE},
167  { "original", "set MPEG Audio Original flag", OFFSET(original), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, AE},
168  { NULL },
169 };
170 
171  static const AVClass libtwolame_class = {
172  .class_name = "libtwolame encoder",
173  .item_name = av_default_item_name,
174  .option = options,
175  .version = LIBAVUTIL_VERSION_INT,
176 };
177 
178  AVCodec ff_libtwolame_encoder = {
179  .name = "libtwolame",
180  .type = AVMEDIA_TYPE_AUDIO,
181  .id = AV_CODEC_ID_MP2,
182  .priv_data_size = sizeof(TWOLAMEContext),
183  .init = twolame_encode_init,
184  .encode2 = twolame_encode_frame,
185  .close = twolame_encode_close,
186  .capabilities = CODEC_CAP_DELAY,
187  .sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLT,
188  AV_SAMPLE_FMT_FLTP,
189  AV_SAMPLE_FMT_S16,
190  AV_SAMPLE_FMT_S16P,
191  AV_SAMPLE_FMT_NONE },
192  .channel_layouts = (const uint64_t[]) { AV_CH_LAYOUT_MONO,
193  AV_CH_LAYOUT_STEREO,
194  0 },
195  .supported_samplerates = (const int[]){ 16000, 22050, 24000, 32000, 44100, 48000, 0 },
196  .long_name = NULL_IF_CONFIG_SMALL("libtwolame MP2 (MPEG audio layer 2)"),
197  .priv_class = &libtwolame_class,
198 };
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