FFmpeg
 All Data Structures Namespaces Files Functions Variables Typedefs Enumerations Enumerator Macros Groups Pages
libtwolame.c
Go to the documentation of this file.
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/common.h"
30 #include "libavutil/opt.h"
31 
32 #include "avcodec.h"
33 #include "internal.h"
34 #include "mpegaudio.h"
35 
36 typedef struct TWOLAMEContext {
37  AVClass *class;
38  int mode;
39  int psymodel;
40  int energy;
42  int copyright;
43  int original;
44  int verbosity;
45 
46  twolame_options *glopts;
47  int64_t next_pts;
49 
51 {
52  TWOLAMEContext *s = avctx->priv_data;
53  twolame_close(&s->glopts);
54  return 0;
55 }
56 
58 {
59  TWOLAMEContext *s = avctx->priv_data;
60  int ret;
61 
62  avctx->frame_size = TWOLAME_SAMPLES_PER_FRAME;
63  avctx->initial_padding = 512 - 32 + 1;
64 
65  s->glopts = twolame_init();
66  if (!s->glopts)
67  return AVERROR(ENOMEM);
68 
69  twolame_set_verbosity(s->glopts, s->verbosity);
70  twolame_set_mode(s->glopts, s->mode);
71  twolame_set_psymodel(s->glopts, s->psymodel);
72  twolame_set_energy_levels(s->glopts, s->energy);
73  twolame_set_error_protection(s->glopts, s->error_protection);
74  twolame_set_copyright(s->glopts, s->copyright);
75  twolame_set_original(s->glopts, s->original);
76 
77  twolame_set_num_channels(s->glopts, avctx->channels);
78  twolame_set_in_samplerate(s->glopts, avctx->sample_rate);
79  twolame_set_out_samplerate(s->glopts, avctx->sample_rate);
80 
81  if (!avctx->bit_rate)
82  avctx->bit_rate = avctx->sample_rate < 28000 ? 160000 : 384000;
83 
84  if (avctx->flags & AV_CODEC_FLAG_QSCALE || !avctx->bit_rate) {
85  twolame_set_VBR(s->glopts, TRUE);
86  twolame_set_VBR_level(s->glopts,
87  avctx->global_quality / (float) FF_QP2LAMBDA);
88  av_log(avctx, AV_LOG_WARNING,
89  "VBR in MP2 is a hack, use another codec that supports it.\n");
90  } else {
91  twolame_set_bitrate(s->glopts, avctx->bit_rate / 1000);
92  }
93 
94  ret = twolame_init_params(s->glopts);
95  if (ret) {
96  twolame_encode_close(avctx);
97  return AVERROR_UNKNOWN;
98  }
99 
100  return 0;
101 }
102 
103 static int twolame_encode_frame(AVCodecContext *avctx, AVPacket *avpkt,
104  const AVFrame *frame, int *got_packet_ptr)
105 {
106  TWOLAMEContext *s = avctx->priv_data;
107  int ret;
108 
109  if ((ret = ff_alloc_packet2(avctx, avpkt, MPA_MAX_CODED_FRAME_SIZE, 0)) < 0)
110  return ret;
111 
112  if (frame) {
113  switch (avctx->sample_fmt) {
114  case AV_SAMPLE_FMT_FLT:
115  ret = twolame_encode_buffer_float32_interleaved(s->glopts,
116  (const float *)frame->data[0],
117  frame->nb_samples,
118  avpkt->data,
119  avpkt->size);
120  break;
121  case AV_SAMPLE_FMT_FLTP:
122  ret = twolame_encode_buffer_float32(s->glopts,
123  (const float *)frame->data[0],
124  (const float *)frame->data[1],
125  frame->nb_samples,
126  avpkt->data, avpkt->size);
127  break;
128  case AV_SAMPLE_FMT_S16:
129  ret = twolame_encode_buffer_interleaved(s->glopts,
130  (const short int *)frame->data[0],
131  frame->nb_samples,
132  avpkt->data, avpkt->size);
133  break;
134  case AV_SAMPLE_FMT_S16P:
135  ret = twolame_encode_buffer(s->glopts,
136  (const short int *)frame->data[0],
137  (const short int *)frame->data[1],
138  frame->nb_samples,
139  avpkt->data, avpkt->size);
140  break;
141  default:
142  av_log(avctx, AV_LOG_ERROR,
143  "Unsupported sample format %d.\n", avctx->sample_fmt);
144  return AVERROR_BUG;
145  }
146  } else {
147  ret = twolame_encode_flush(s->glopts, avpkt->data, avpkt->size);
148  }
149 
150  if (!ret) // no bytes written
151  return 0;
152  if (ret < 0) // twolame error
153  return AVERROR_UNKNOWN;
154 
155  if (frame) {
156  avpkt->duration = ff_samples_to_time_base(avctx, frame->nb_samples);
157  if (frame->pts != AV_NOPTS_VALUE)
158  avpkt->pts = frame->pts - ff_samples_to_time_base(avctx, avctx->initial_padding);
159  } else {
160  avpkt->pts = s->next_pts;
161  }
162  // this is for setting pts for flushed packet(s).
163  if (avpkt->pts != AV_NOPTS_VALUE)
164  s->next_pts = avpkt->pts + avpkt->duration;
165 
166  av_shrink_packet(avpkt, ret);
167  *got_packet_ptr = 1;
168  return 0;
169 }
170 
171 #define OFFSET(x) offsetof(TWOLAMEContext, x)
172 #define AE AV_OPT_FLAG_AUDIO_PARAM | AV_OPT_FLAG_ENCODING_PARAM
173 static const AVOption options[] = {
174  { "mode", "Mpeg Mode", OFFSET(mode), AV_OPT_TYPE_INT, { .i64 = TWOLAME_AUTO_MODE }, TWOLAME_AUTO_MODE, TWOLAME_MONO, AE, "mode"},
175  { "auto", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = TWOLAME_AUTO_MODE }, 0, 0, AE, "mode" },
176  { "stereo", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = TWOLAME_STEREO }, 0, 0, AE, "mode" },
177  { "joint_stereo", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = TWOLAME_JOINT_STEREO }, 0, 0, AE, "mode" },
178  { "dual_channel", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = TWOLAME_DUAL_CHANNEL }, 0, 0, AE, "mode" },
179  { "mono", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = TWOLAME_MONO }, 0, 0, AE, "mode" },
180  { "psymodel", "Psychoacoustic Model", OFFSET(psymodel), AV_OPT_TYPE_INT, { .i64 = 3 }, -1, 4, AE},
181  { "energy_levels","enable energy levels", OFFSET(energy), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, AE},
182  { "error_protection","enable CRC error protection", OFFSET(error_protection), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, AE},
183  { "copyright", "set MPEG Audio Copyright flag", OFFSET(copyright), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, AE},
184  { "original", "set MPEG Audio Original flag", OFFSET(original), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, AE},
185  { "verbosity", "set library optput level (0-10)", OFFSET(verbosity), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 10, AE},
186  { NULL },
187 };
188 
189 static const AVClass twolame_class = {
190  .class_name = "libtwolame encoder",
191  .item_name = av_default_item_name,
192  .option = options,
193  .version = LIBAVUTIL_VERSION_INT,
194 };
195 
197  { "b", "0" },
198  { NULL },
199 };
200 
201 static const int twolame_samplerates[] = {
202  16000, 22050, 24000, 32000, 44100, 48000, 0
203 };
204 
206  .name = "libtwolame",
207  .long_name = NULL_IF_CONFIG_SMALL("libtwolame MP2 (MPEG audio layer 2)"),
208  .type = AVMEDIA_TYPE_AUDIO,
209  .id = AV_CODEC_ID_MP2,
210  .priv_data_size = sizeof(TWOLAMEContext),
212  .encode2 = twolame_encode_frame,
213  .close = twolame_encode_close,
214  .capabilities = AV_CODEC_CAP_DELAY,
215  .defaults = twolame_defaults,
216  .priv_class = &twolame_class,
217  .sample_fmts = (const enum AVSampleFormat[]) {
223  },
224  .channel_layouts = (const uint64_t[]) {
227  0 },
228  .supported_samplerates = twolame_samplerates,
229 };
#define MPA_MAX_CODED_FRAME_SIZE
Definition: mpegaudio.h:39
float, planar
Definition: samplefmt.h:69
#define NULL
Definition: coverity.c:32
const char * s
Definition: avisynth_c.h:768
This structure describes decoded (raw) audio or video data.
Definition: frame.h:184
static av_cold int twolame_encode_init(AVCodecContext *avctx)
Definition: libtwolame.c:57
AVOption.
Definition: opt.h:245
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
int64_t bit_rate
the average bitrate
Definition: avcodec.h:1740
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
void av_shrink_packet(AVPacket *pkt, int size)
Reduce packet size, correctly zeroing padding.
Definition: avpacket.c:101
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
int size
Definition: avcodec.h:1601
#define AE
Definition: libtwolame.c:172
#define AV_CH_LAYOUT_STEREO
AVCodec.
Definition: avcodec.h:3599
const char * class_name
The name of the class; usually it is the same name as the context structure type to which the AVClass...
Definition: log.h:72
#define AV_CODEC_CAP_DELAY
Encoder or decoder requires flushing with NULL input at the end in order to give the complete and cor...
Definition: avcodec.h:983
AVCodec ff_libtwolame_encoder
Definition: libtwolame.c:205
static const AVCodecDefault twolame_defaults[]
Definition: libtwolame.c:196
enum AVSampleFormat sample_fmt
audio sample format
Definition: avcodec.h:2445
#define av_cold
Definition: attributes.h:82
mode
Definition: f_perms.c:27
AVOptions.
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: avcodec.h:1618
int64_t pts
Presentation timestamp in time_base units (time when frame should be shown to user).
Definition: frame.h:268
static AVFrame * frame
uint8_t * data
Definition: avcodec.h:1600
static const int twolame_samplerates[]
Definition: libtwolame.c:201
#define av_log(a,...)
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
av_default_item_name
#define AVERROR(e)
Definition: error.h:43
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:176
int initial_padding
Audio only.
Definition: avcodec.h:3365
int flags
AV_CODEC_FLAG_*.
Definition: avcodec.h:1770
const char * name
Name of the codec implementation.
Definition: avcodec.h:3606
static const AVOption options[]
Definition: libtwolame.c:173
#define AV_CODEC_FLAG_QSCALE
Use fixed qscale.
Definition: avcodec.h:832
#define TRUE
Definition: windows2linux.h:33
twolame_options * glopts
Definition: libtwolame.c:46
int error_protection
Definition: libtwolame.c:41
int frame_size
Number of samples per channel in an audio frame.
Definition: avcodec.h:2457
Libavcodec external API header.
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:58
int sample_rate
samples per second
Definition: avcodec.h:2437
#define OFFSET(x)
Definition: libtwolame.c:171
main external API structure.
Definition: avcodec.h:1675
#define AVERROR_BUG
Internal bug, also see AVERROR_BUG2.
Definition: error.h:50
Describe the class of an AVClass context structure.
Definition: log.h:67
static const AVClass twolame_class
Definition: libtwolame.c:189
int ff_alloc_packet2(AVCodecContext *avctx, AVPacket *avpkt, int64_t size, int64_t min_size)
Check AVPacket size and/or allocate data.
Definition: utils.c:1710
int global_quality
Global quality for codecs which cannot change it per frame.
Definition: avcodec.h:1756
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:198
int64_t next_pts
Definition: libtwolame.c:47
common internal api header.
common internal and external API header
static int twolame_encode_frame(AVCodecContext *avctx, AVPacket *avpkt, const AVFrame *frame, int *got_packet_ptr)
Definition: libtwolame.c:103
static av_cold int twolame_encode_close(AVCodecContext *avctx)
Definition: libtwolame.c:50
signed 16 bits
Definition: samplefmt.h:61
mpeg audio declarations for both encoder and decoder.
#define AVERROR_UNKNOWN
Unknown error, typically from an external library.
Definition: error.h:71
void * priv_data
Definition: avcodec.h:1717
int channels
number of audio channels
Definition: avcodec.h:2438
#define FF_QP2LAMBDA
factor to convert from H.263 QP to lambda
Definition: avutil.h:221
static enum AVSampleFormat sample_fmts[]
Definition: adpcmenc.c:701
signed 16 bits, planar
Definition: samplefmt.h:67
static av_always_inline int64_t ff_samples_to_time_base(AVCodecContext *avctx, int64_t samples)
Rescale from sample rate to AVCodecContext.time_base.
Definition: internal.h:248
static const AVCodecDefault defaults[]
Definition: dcaenc.c:975
#define AV_CH_LAYOUT_MONO
This structure stores compressed data.
Definition: avcodec.h:1577
int nb_samples
number of audio samples (per channel) described by this frame
Definition: frame.h:241
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:1593
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:242