FFmpeg
libshine.c
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1 /*
2  * Interface to libshine for mp3 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 #include <shine/layer3.h>
23 
24 #include "libavutil/intreadwrite.h"
25 #include "audio_frame_queue.h"
26 #include "avcodec.h"
27 #include "internal.h"
28 #include "mpegaudio.h"
29 #include "mpegaudiodecheader.h"
30 
31 #define BUFFER_SIZE (4096 * 20)
32 
33 typedef struct SHINEContext {
34  shine_config_t config;
35  shine_t shine;
39 } SHINEContext;
40 
42 {
43  SHINEContext *s = avctx->priv_data;
44 
45  if (avctx->channels <= 0 || avctx->channels > 2){
46  av_log(avctx, AV_LOG_ERROR, "only mono or stereo is supported\n");
47  return AVERROR(EINVAL);
48  }
49 
50  shine_set_config_mpeg_defaults(&s->config.mpeg);
51  if (avctx->bit_rate)
52  s->config.mpeg.bitr = avctx->bit_rate / 1000;
53  s->config.mpeg.mode = avctx->channels == 2 ? STEREO : MONO;
54  s->config.wave.samplerate = avctx->sample_rate;
55  s->config.wave.channels = avctx->channels == 2 ? PCM_STEREO : PCM_MONO;
56  if (shine_check_config(s->config.wave.samplerate, s->config.mpeg.bitr) < 0) {
57  av_log(avctx, AV_LOG_ERROR, "invalid configuration\n");
58  return AVERROR(EINVAL);
59  }
60  s->shine = shine_initialise(&s->config);
61  if (!s->shine)
62  return AVERROR(ENOMEM);
63  avctx->frame_size = shine_samples_per_pass(s->shine);
64  ff_af_queue_init(avctx, &s->afq);
65  return 0;
66 }
67 
68 static int libshine_encode_frame(AVCodecContext *avctx, AVPacket *avpkt,
69  const AVFrame *frame, int *got_packet_ptr)
70 {
71  SHINEContext *s = avctx->priv_data;
72  MPADecodeHeader hdr;
73  unsigned char *data;
74  int written;
75  int ret, len;
76 
77  if (frame)
78  data = shine_encode_buffer(s->shine, (int16_t **)frame->data, &written);
79  else
80  data = shine_flush(s->shine, &written);
81  if (written < 0)
82  return -1;
83  if (written > 0) {
84  if (s->buffer_index + written > BUFFER_SIZE) {
85  av_log(avctx, AV_LOG_ERROR, "internal buffer too small\n");
86  return AVERROR_BUG;
87  }
88  memcpy(s->buffer + s->buffer_index, data, written);
89  s->buffer_index += written;
90  }
91  if (frame) {
92  if ((ret = ff_af_queue_add(&s->afq, frame)) < 0)
93  return ret;
94  }
95 
96  if (s->buffer_index < 4 || !s->afq.frame_count)
97  return 0;
99  av_log(avctx, AV_LOG_ERROR, "free format output not supported\n");
100  return -1;
101  }
102 
103  len = hdr.frame_size;
104  if (len <= s->buffer_index) {
105  if ((ret = ff_alloc_packet2(avctx, avpkt, len, 0)))
106  return ret;
107  memcpy(avpkt->data, s->buffer, len);
108  s->buffer_index -= len;
109  memmove(s->buffer, s->buffer + len, s->buffer_index);
110 
111  ff_af_queue_remove(&s->afq, avctx->frame_size, &avpkt->pts,
112  &avpkt->duration);
113 
114  avpkt->size = len;
115  *got_packet_ptr = 1;
116  }
117  return 0;
118 }
119 
121 {
122  SHINEContext *s = avctx->priv_data;
123 
124  ff_af_queue_close(&s->afq);
125  shine_close(s->shine);
126  return 0;
127 }
128 
129 static const int libshine_sample_rates[] = {
130  44100, 48000, 32000, 0
131 };
132 
134  .name = "libshine",
135  .long_name = NULL_IF_CONFIG_SMALL("libshine MP3 (MPEG audio layer 3)"),
136  .type = AVMEDIA_TYPE_AUDIO,
137  .id = AV_CODEC_ID_MP3,
138  .priv_data_size = sizeof(SHINEContext),
140  .encode2 = libshine_encode_frame,
141  .close = libshine_encode_close,
142  .capabilities = AV_CODEC_CAP_DELAY,
143  .sample_fmts = (const enum AVSampleFormat[]){ AV_SAMPLE_FMT_S16P,
145  .supported_samplerates = libshine_sample_rates,
146  .channel_layouts = (const uint64_t[]) { AV_CH_LAYOUT_MONO,
148  0 },
149  .wrapper_name = "libshine",
150 };
void ff_af_queue_remove(AudioFrameQueue *afq, int nb_samples, int64_t *pts, int64_t *duration)
Remove frame(s) from the queue.
This structure describes decoded (raw) audio or video data.
Definition: frame.h:295
shine_config_t config
Definition: libshine.c:34
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:100
int64_t bit_rate
the average bitrate
Definition: avcodec.h:1621
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
int size
Definition: avcodec.h:1484
#define AV_CH_LAYOUT_STEREO
AVCodec.
Definition: avcodec.h:3495
#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:1012
int ff_alloc_packet2(AVCodecContext *avctx, AVPacket *avpkt, int64_t size, int64_t min_size)
Check AVPacket size and/or allocate data.
Definition: encode.c:32
uint8_t
#define av_cold
Definition: attributes.h:82
av_cold void ff_af_queue_init(AVCodecContext *avctx, AudioFrameQueue *afq)
Initialize AudioFrameQueue.
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: avcodec.h:1501
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_RB32
Definition: bytestream.h:87
static av_cold int libshine_encode_close(AVCodecContext *avctx)
Definition: libshine.c:120
uint8_t * data
Definition: avcodec.h:1483
int avpriv_mpegaudio_decode_header(MPADecodeHeader *s, uint32_t header)
#define av_log(a,...)
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
preferred ID for decoding MPEG audio layer 1, 2 or 3
Definition: avcodec.h:568
const char * name
Name of the codec implementation.
Definition: avcodec.h:3502
int ff_af_queue_add(AudioFrameQueue *afq, const AVFrame *f)
Add a frame to the queue.
uint8_t buffer[BUFFER_SIZE]
Definition: libshine.c:36
static av_cold int libshine_encode_init(AVCodecContext *avctx)
Definition: libshine.c:41
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
#define s(width, name)
Definition: cbs_vp9.c:257
#define BUFFER_SIZE
Definition: libshine.c:31
int frame_size
Number of samples per channel in an audio frame.
Definition: avcodec.h:2251
Libavcodec external API header.
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:58
AVCodec ff_libshine_encoder
Definition: libshine.c:133
int sample_rate
samples per second
Definition: avcodec.h:2231
main external API structure.
Definition: avcodec.h:1571
AudioFrameQueue afq
Definition: libshine.c:38
#define AVERROR_BUG
Internal bug, also see AVERROR_BUG2.
Definition: error.h:50
#define MONO
Definition: cook.c:60
int buffer_index
Definition: libshine.c:37
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:309
MPEG Audio header decoder.
common internal api header.
#define STEREO
Definition: cook.c:61
static const int libshine_sample_rates[]
Definition: libshine.c:129
mpeg audio declarations for both encoder and decoder.
void * priv_data
Definition: avcodec.h:1598
int len
int channels
number of audio channels
Definition: avcodec.h:2232
void ff_af_queue_close(AudioFrameQueue *afq)
Close AudioFrameQueue.
static enum AVSampleFormat sample_fmts[]
Definition: adpcmenc.c:701
static int libshine_encode_frame(AVCodecContext *avctx, AVPacket *avpkt, const AVFrame *frame, int *got_packet_ptr)
Definition: libshine.c:68
signed 16 bits, planar
Definition: samplefmt.h:67
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions
#define AV_CH_LAYOUT_MONO
This structure stores compressed data.
Definition: avcodec.h:1460
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:1476
shine_t shine
Definition: libshine.c:35
GLuint buffer
Definition: opengl_enc.c:101