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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;
31  int64_t size;
32  int64_t samples;
33  int64_t loopstart;
34  int64_t loopend;
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 */
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  avio_flush(pb);
105 
106  return 0;
107 }
108 
110 {
111  AVIOContext *pb = s->pb;
112  ASTMuxContext *ast = s->priv_data;
113  AVCodecParameters *par = s->streams[0]->codecpar;
114  int size = pkt->size / par->channels;
115 
116  if (s->streams[0]->nb_frames == 0)
117  ast->fbs = size;
118 
119  ffio_wfourcc(pb, "BLCK");
120  avio_wb32(pb, size); /* Block size */
121 
122  /* padding */
123  avio_wb64(pb, 0);
124  avio_wb64(pb, 0);
125  avio_wb64(pb, 0);
126 
127  avio_write(pb, pkt->data, pkt->size);
128 
129  return 0;
130 }
131 
133 {
134  AVIOContext *pb = s->pb;
135  ASTMuxContext *ast = s->priv_data;
136  AVCodecParameters *par = s->streams[0]->codecpar;
137  int64_t file_size = avio_tell(pb);
138  int64_t samples = (file_size - 64 - (32 * s->streams[0]->nb_frames)) / par->block_align; /* PCM_S16BE_PLANAR */
139 
140  av_log(s, AV_LOG_DEBUG, "total samples: %"PRId64"\n", samples);
141 
142  if (s->pb->seekable) {
143  /* Number of samples */
144  avio_seek(pb, ast->samples, SEEK_SET);
145  avio_wb32(pb, samples);
146 
147  /* Loopstart if provided */
148  if (ast->loopstart > 0) {
149  if (ast->loopstart >= samples) {
150  av_log(s, AV_LOG_WARNING, "Loopstart value is out of range and will be ignored\n");
151  ast->loopstart = -1;
152  avio_skip(pb, 4);
153  } else
154  avio_wb32(pb, ast->loopstart);
155  } else
156  avio_skip(pb, 4);
157 
158  /* Loopend if provided. Otherwise number of samples again */
159  if (ast->loopend && ast->loopstart >= 0) {
160  if (ast->loopend > samples) {
161  av_log(s, AV_LOG_WARNING, "Loopend value is out of range and will be ignored\n");
162  ast->loopend = samples;
163  }
164  avio_wb32(pb, ast->loopend);
165  } else {
166  avio_wb32(pb, samples);
167  }
168 
169  /* Size of first block */
170  avio_wb32(pb, ast->fbs);
171 
172  /* File size minus header */
173  avio_seek(pb, ast->size, SEEK_SET);
174  avio_wb32(pb, file_size - 64);
175 
176  /* Loop flag */
177  if (ast->loopstart >= 0) {
178  avio_skip(pb, 6);
179  avio_wb16(pb, 0xFFFF);
180  }
181 
182  avio_seek(pb, file_size, SEEK_SET);
183  avio_flush(pb);
184  }
185  return 0;
186 }
187 
188 #define OFFSET(obj) offsetof(ASTMuxContext, obj)
189 static const AVOption options[] = {
190  { "loopstart", "Loopstart position in milliseconds.", OFFSET(loopstart), AV_OPT_TYPE_INT64, { .i64 = -1 }, -1, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM },
191  { "loopend", "Loopend position in milliseconds.", OFFSET(loopend), AV_OPT_TYPE_INT64, { .i64 = 0 }, 0, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM },
192  { NULL },
193 };
194 
195 static const AVClass ast_muxer_class = {
196  .class_name = "AST muxer",
197  .item_name = av_default_item_name,
198  .option = options,
199  .version = LIBAVUTIL_VERSION_INT,
200 };
201 
203  .name = "ast",
204  .long_name = NULL_IF_CONFIG_SMALL("AST (Audio Stream)"),
205  .extensions = "ast",
206  .priv_data_size = sizeof(ASTMuxContext),
207  .audio_codec = AV_CODEC_ID_PCM_S16BE_PLANAR,
208  .video_codec = AV_CODEC_ID_NONE,
212  .priv_class = &ast_muxer_class,
213  .codec_tag = (const AVCodecTag* const []){ff_codec_ast_tags, 0},
214 };
static int ast_write_packet(AVFormatContext *s, AVPacket *pkt)
Definition: astenc.c:109
void avio_wb64(AVIOContext *s, uint64_t val)
Definition: aviobuf.c:440
#define NULL
Definition: coverity.c:32
const char * s
Definition: avisynth_c.h:768
Bytestream IO Context.
Definition: avio.h:147
AVOption.
Definition: opt.h:245
static const AVOption options[]
Definition: astenc.c:189
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
#define LIBAVUTIL_VERSION_INT
Definition: version.h:70
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3953
int size
Definition: avcodec.h:1591
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:230
#define CHECK_LOOP(type)
Definition: astenc.c:38
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:304
unsigned int ff_codec_get_tag(const AVCodecTag *tags, enum AVCodecID id)
Definition: utils.c:2949
static AVPacket pkt
This struct describes the properties of an encoded stream.
Definition: avcodec.h:3945
Format I/O context.
Definition: avformat.h:1327
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
void avio_wl32(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:346
AVOptions.
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:90
AVOutputFormat ff_ast_muxer
Definition: astenc.c:202
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1395
uint8_t * data
Definition: avcodec.h:1590
ptrdiff_t size
Definition: opengl_enc.c:101
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:511
void avio_write(AVIOContext *s, const unsigned char *buf, int size)
Definition: aviobuf.c:204
static av_always_inline void ffio_wfourcc(AVIOContext *pb, const uint8_t *s)
Definition: avio_internal.h:66
#define av_log(a,...)
#define AV_OPT_FLAG_ENCODING_PARAM
a generic parameter which can be set by the user for muxing or encoding
Definition: opt.h:275
#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
static int ast_write_trailer(AVFormatContext *s)
Definition: astenc.c:132
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:176
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:197
unsigned int nb_streams
Number of elements in AVFormatContext.streams.
Definition: avformat.h:1383
int block_align
Audio only.
Definition: avcodec.h:4070
int seekable
A combination of AVIO_SEEKABLE_ flags or 0 when the stream is not seekable.
Definition: avio.h:243
int void avio_flush(AVIOContext *s)
Force flushing of buffered data.
Definition: aviobuf.c:224
static int write_trailer(AVFormatContext *s1)
Definition: v4l2enc.c:94
const char * name
Definition: avformat.h:524
int64_t samples
Definition: astenc.c:32
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:62
AVIOContext * pb
I/O context.
Definition: avformat.h:1369
Describe the class of an AVClass context structure.
Definition: log.h:67
void avio_wb16(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:452
int sample_rate
Audio only.
Definition: avcodec.h:4063
Main libavformat public API header.
static int ast_write_header(AVFormatContext *s)
Definition: astenc.c:47
int64_t loopstart
Definition: astenc.c:33
int64_t nb_frames
number of frames in this stream if known or 0
Definition: avformat.h:934
#define OFFSET(obj)
Definition: astenc.c:188
const AVCodecTag ff_codec_ast_tags[]
Definition: ast.c:25
void * priv_data
Format private data.
Definition: avformat.h:1355
static void write_header(FFV1Context *f)
Definition: ffv1enc.c:344
int64_t size
Definition: astenc.c:31
int channels
Audio only.
Definition: avcodec.h:4059
int64_t loopend
Definition: astenc.c:34
void avio_wb32(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:354
void INT64 start
Definition: avisynth_c.h:690
AVCodecParameters * codecpar
Definition: avformat.h:1230
This structure stores compressed data.
Definition: avcodec.h:1567
static int write_packet(AVFormatContext *s1, AVPacket *pkt)
Definition: v4l2enc.c:86
static const AVClass ast_muxer_class
Definition: astenc.c:195