FFmpeg  4.4.6
astenc.c
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1 /*
2  * AST muxer
3  * Copyright (c) 2012 James Almer
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 "avformat.h"
23 #include "avio_internal.h"
24 #include "internal.h"
25 #include "ast.h"
26 #include "libavutil/mathematics.h"
27 #include "libavutil/opt.h"
28 
29 typedef struct ASTMuxContext {
30  AVClass *class;
35  int fbs;
37 
38 #define CHECK_LOOP(type) \
39  if (ast->loop ## type > 0) { \
40  ast->loop ## type = av_rescale_rnd(ast->loop ## type, par->sample_rate, 1000, AV_ROUND_DOWN); \
41  if (ast->loop ## type < 0 || ast->loop ## type > UINT_MAX) { \
42  av_log(s, AV_LOG_ERROR, "Invalid loop" #type " value\n"); \
43  return AVERROR(EINVAL); \
44  } \
45  }
46 
48 {
49  ASTMuxContext *ast = s->priv_data;
50  AVIOContext *pb = s->pb;
51  AVCodecParameters *par;
52  unsigned int codec_tag;
53 
54  if (s->nb_streams == 1) {
55  par = s->streams[0]->codecpar;
56  } else {
57  av_log(s, AV_LOG_ERROR, "only one stream is supported\n");
58  return AVERROR(EINVAL);
59  }
60 
61  if (par->codec_id == AV_CODEC_ID_ADPCM_AFC) {
62  av_log(s, AV_LOG_ERROR, "muxing ADPCM AFC is not implemented\n");
63  return AVERROR_PATCHWELCOME;
64  }
65 
66  codec_tag = ff_codec_get_tag(ff_codec_ast_tags, par->codec_id);
67  if (!codec_tag) {
68  av_log(s, AV_LOG_ERROR, "unsupported codec\n");
69  return AVERROR(EINVAL);
70  }
71 
72  if (ast->loopend > 0 && ast->loopstart >= ast->loopend) {
73  av_log(s, AV_LOG_ERROR, "loopend can't be less or equal to loopstart\n");
74  return AVERROR(EINVAL);
75  }
76 
77  /* Convert milliseconds to samples */
78  CHECK_LOOP(start)
79  CHECK_LOOP(end)
80 
81  ffio_wfourcc(pb, "STRM");
82 
83  ast->size = avio_tell(pb);
84  avio_wb32(pb, 0); /* File size minus header */
85  avio_wb16(pb, codec_tag);
86  avio_wb16(pb, 16); /* Bit depth */
87  avio_wb16(pb, par->channels);
88  avio_wb16(pb, 0); /* Loop flag */
89  avio_wb32(pb, par->sample_rate);
90 
91  ast->samples = avio_tell(pb);
92  avio_wb32(pb, 0); /* Number of samples */
93  avio_wb32(pb, 0); /* Loopstart */
94  avio_wb32(pb, 0); /* Loopend */
95  avio_wb32(pb, 0); /* Size of first block */
96 
97  /* Unknown */
98  avio_wb32(pb, 0);
99  avio_wl32(pb, 0x7F);
100  avio_wb64(pb, 0);
101  avio_wb64(pb, 0);
102  avio_wb32(pb, 0);
103 
104  return 0;
105 }
106 
108 {
109  AVIOContext *pb = s->pb;
110  ASTMuxContext *ast = s->priv_data;
111  AVCodecParameters *par = s->streams[0]->codecpar;
112  int size = pkt->size / par->channels;
113 
114  if (s->streams[0]->nb_frames == 0)
115  ast->fbs = size;
116 
117  ffio_wfourcc(pb, "BLCK");
118  avio_wb32(pb, size); /* Block size */
119 
120  /* padding */
121  avio_wb64(pb, 0);
122  avio_wb64(pb, 0);
123  avio_wb64(pb, 0);
124 
125  avio_write(pb, pkt->data, pkt->size);
126 
127  return 0;
128 }
129 
131 {
132  AVIOContext *pb = s->pb;
133  ASTMuxContext *ast = s->priv_data;
134  AVCodecParameters *par = s->streams[0]->codecpar;
135  int64_t file_size = avio_tell(pb);
136  int64_t samples = (file_size - 64 - (32 * s->streams[0]->nb_frames)) / par->block_align; /* PCM_S16BE_PLANAR */
137 
138  av_log(s, AV_LOG_DEBUG, "total samples: %"PRId64"\n", samples);
139 
140  if (s->pb->seekable & AVIO_SEEKABLE_NORMAL) {
141  /* Number of samples */
142  avio_seek(pb, ast->samples, SEEK_SET);
143  avio_wb32(pb, samples);
144 
145  /* Loopstart if provided */
146  if (ast->loopstart > 0) {
147  if (ast->loopstart >= samples) {
148  av_log(s, AV_LOG_WARNING, "Loopstart value is out of range and will be ignored\n");
149  ast->loopstart = -1;
150  avio_skip(pb, 4);
151  } else
152  avio_wb32(pb, ast->loopstart);
153  } else
154  avio_skip(pb, 4);
155 
156  /* Loopend if provided. Otherwise number of samples again */
157  if (ast->loopend && ast->loopstart >= 0) {
158  if (ast->loopend > samples) {
159  av_log(s, AV_LOG_WARNING, "Loopend value is out of range and will be ignored\n");
160  ast->loopend = samples;
161  }
162  avio_wb32(pb, ast->loopend);
163  } else {
164  avio_wb32(pb, samples);
165  }
166 
167  /* Size of first block */
168  avio_wb32(pb, ast->fbs);
169 
170  /* File size minus header */
171  avio_seek(pb, ast->size, SEEK_SET);
172  avio_wb32(pb, file_size - 64);
173 
174  /* Loop flag */
175  if (ast->loopstart >= 0) {
176  avio_skip(pb, 6);
177  avio_wb16(pb, 0xFFFF);
178  }
179 
180  avio_seek(pb, file_size, SEEK_SET);
181  }
182  return 0;
183 }
184 
185 #define OFFSET(obj) offsetof(ASTMuxContext, obj)
186 static const AVOption options[] = {
187  { "loopstart", "Loopstart position in milliseconds.", OFFSET(loopstart), AV_OPT_TYPE_INT64, { .i64 = -1 }, -1, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM },
188  { "loopend", "Loopend position in milliseconds.", OFFSET(loopend), AV_OPT_TYPE_INT64, { .i64 = 0 }, 0, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM },
189  { NULL },
190 };
191 
192 static const AVClass ast_muxer_class = {
193  .class_name = "AST muxer",
194  .item_name = av_default_item_name,
195  .option = options,
196  .version = LIBAVUTIL_VERSION_INT,
197 };
198 
200  .name = "ast",
201  .long_name = NULL_IF_CONFIG_SMALL("AST (Audio Stream)"),
202  .extensions = "ast",
203  .priv_data_size = sizeof(ASTMuxContext),
204  .audio_codec = AV_CODEC_ID_PCM_S16BE_PLANAR,
205  .video_codec = AV_CODEC_ID_NONE,
209  .priv_class = &ast_muxer_class,
210  .codec_tag = ff_ast_codec_tags_list,
211 };
const AVCodecTag ff_codec_ast_tags[]
Definition: ast.c:26
const AVCodecTag *const ff_ast_codec_tags_list[]
Definition: ast.c:32
static const AVOption options[]
Definition: astenc.c:186
static int ast_write_trailer(AVFormatContext *s)
Definition: astenc.c:130
#define OFFSET(obj)
Definition: astenc.c:185
static int ast_write_packet(AVFormatContext *s, AVPacket *pkt)
Definition: astenc.c:107
AVOutputFormat ff_ast_muxer
Definition: astenc.c:199
static const AVClass ast_muxer_class
Definition: astenc.c:192
static int ast_write_header(AVFormatContext *s)
Definition: astenc.c:47
#define CHECK_LOOP(type)
Definition: astenc.c:38
Main libavformat public API header.
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:253
#define AVIO_SEEKABLE_NORMAL
Seeking works like for a local file.
Definition: avio.h:40
void avio_wl32(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:375
void avio_wb32(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:383
void avio_wb16(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:461
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:557
void avio_wb64(AVIOContext *s, uint64_t val)
Definition: aviobuf.c:449
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:337
void avio_write(AVIOContext *s, const unsigned char *buf, int size)
Definition: aviobuf.c:225
static av_always_inline void ffio_wfourcc(AVIOContext *pb, const uint8_t *s)
Definition: avio_internal.h:58
#define s(width, name)
Definition: cbs_vp9.c:257
#define NULL
Definition: coverity.c:32
long long int64_t
Definition: coverity.c:34
static void write_packet(OutputFile *of, AVPacket *pkt, OutputStream *ost, int unqueue)
Definition: ffmpeg.c:730
static void write_header(FFV1Context *f)
Definition: ffv1enc.c:346
@ AV_OPT_TYPE_INT64
Definition: opt.h:226
@ AV_CODEC_ID_PCM_S16BE_PLANAR
Definition: codec_id.h:343
@ AV_CODEC_ID_NONE
Definition: codec_id.h:47
@ AV_CODEC_ID_ADPCM_AFC
Definition: codec_id.h:385
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:62
#define AVERROR(e)
Definition: error.h:43
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:215
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:200
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:194
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:235
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
unsigned int ff_codec_get_tag(const AVCodecTag *tags, enum AVCodecID id)
Definition: utils.c:3121
common internal API header
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
AVOptions.
#define AV_OPT_FLAG_ENCODING_PARAM
a generic parameter which can be set by the user for muxing or encoding
Definition: opt.h:278
int64_t samples
Definition: astenc.c:32
int64_t size
Definition: astenc.c:31
int64_t loopstart
Definition: astenc.c:33
int64_t loopend
Definition: astenc.c:34
Describe the class of an AVClass context structure.
Definition: log.h:67
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
This struct describes the properties of an encoded stream.
Definition: codec_par.h:52
int channels
Audio only.
Definition: codec_par.h:166
int block_align
Audio only.
Definition: codec_par.h:177
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
int sample_rate
Audio only.
Definition: codec_par.h:170
Format I/O context.
Definition: avformat.h:1232
Bytestream IO Context.
Definition: avio.h:161
AVOption.
Definition: opt.h:248
const char * name
Definition: avformat.h:491
This structure stores compressed data.
Definition: packet.h:346
int size
Definition: packet.h:370
uint8_t * data
Definition: packet.h:369
#define av_log(a,...)
AVPacket * pkt
Definition: movenc.c:59
int size
static int write_trailer(AVFormatContext *s1)
Definition: v4l2enc.c:98