FFmpeg
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 "mux.h"
27 #include "libavutil/mathematics.h"
28 #include "libavutil/opt.h"
29 
30 typedef struct ASTMuxContext {
31  AVClass *class;
32  int64_t size;
33  int64_t samples;
34  int64_t loopstart;
35  int64_t loopend;
36  int fbs;
38 
39 #define CHECK_LOOP(type) \
40  if (ast->loop ## type > 0) { \
41  ast->loop ## type = av_rescale_rnd(ast->loop ## type, par->sample_rate, 1000, AV_ROUND_DOWN); \
42  if (ast->loop ## type < 0 || ast->loop ## type > UINT_MAX) { \
43  av_log(s, AV_LOG_ERROR, "Invalid loop" #type " value\n"); \
44  return AVERROR(EINVAL); \
45  } \
46  }
47 
49 {
50  ASTMuxContext *ast = s->priv_data;
51  AVIOContext *pb = s->pb;
52  AVCodecParameters *par = s->streams[0]->codecpar;
53  unsigned int codec_tag;
54 
55  if (par->codec_id == AV_CODEC_ID_ADPCM_AFC) {
56  av_log(s, AV_LOG_ERROR, "muxing ADPCM AFC is not implemented\n");
57  return AVERROR_PATCHWELCOME;
58  }
59 
60  codec_tag = ff_codec_get_tag(ff_codec_ast_tags, par->codec_id);
61  if (!codec_tag) {
62  av_log(s, AV_LOG_ERROR, "unsupported codec\n");
63  return AVERROR(EINVAL);
64  }
65 
66  if (ast->loopend > 0 && ast->loopstart >= ast->loopend) {
67  av_log(s, AV_LOG_ERROR, "loopend can't be less or equal to loopstart\n");
68  return AVERROR(EINVAL);
69  }
70 
71  /* Convert milliseconds to samples */
72  CHECK_LOOP(start)
73  CHECK_LOOP(end)
74 
75  ffio_wfourcc(pb, "STRM");
76 
77  ast->size = avio_tell(pb);
78  avio_wb32(pb, 0); /* File size minus header */
79  avio_wb16(pb, codec_tag);
80  avio_wb16(pb, 16); /* Bit depth */
82  avio_wb16(pb, 0); /* Loop flag */
83  avio_wb32(pb, par->sample_rate);
84 
85  ast->samples = avio_tell(pb);
86  avio_wb32(pb, 0); /* Number of samples */
87  avio_wb32(pb, 0); /* Loopstart */
88  avio_wb32(pb, 0); /* Loopend */
89  avio_wb32(pb, 0); /* Size of first block */
90 
91  /* Unknown */
92  avio_wb32(pb, 0);
93  avio_wl32(pb, 0x7F);
94  avio_wb64(pb, 0);
95  avio_wb64(pb, 0);
96  avio_wb32(pb, 0);
97 
98  return 0;
99 }
100 
102 {
103  AVIOContext *pb = s->pb;
104  ASTMuxContext *ast = s->priv_data;
105  AVCodecParameters *par = s->streams[0]->codecpar;
106  int size = pkt->size / par->ch_layout.nb_channels;
107 
108  if (s->streams[0]->nb_frames == 0)
109  ast->fbs = size;
110 
111  ffio_wfourcc(pb, "BLCK");
112  avio_wb32(pb, size); /* Block size */
113 
114  /* padding */
115  ffio_fill(pb, 0, 24);
116 
117  avio_write(pb, pkt->data, pkt->size);
118 
119  return 0;
120 }
121 
123 {
124  AVIOContext *pb = s->pb;
125  ASTMuxContext *ast = s->priv_data;
126  AVCodecParameters *par = s->streams[0]->codecpar;
127  int64_t file_size = avio_tell(pb);
128  int64_t samples = (file_size - 64 - (32 * s->streams[0]->nb_frames)) / par->block_align; /* PCM_S16BE_PLANAR */
129 
130  av_log(s, AV_LOG_DEBUG, "total samples: %"PRId64"\n", samples);
131 
132  if (s->pb->seekable & AVIO_SEEKABLE_NORMAL) {
133  /* Number of samples */
134  avio_seek(pb, ast->samples, SEEK_SET);
135  avio_wb32(pb, samples);
136 
137  /* Loopstart if provided */
138  if (ast->loopstart > 0) {
139  if (ast->loopstart >= samples) {
140  av_log(s, AV_LOG_WARNING, "Loopstart value is out of range and will be ignored\n");
141  ast->loopstart = -1;
142  avio_skip(pb, 4);
143  } else {
144  avio_wb32(pb, ast->loopstart);
145  }
146  } else {
147  avio_skip(pb, 4);
148  }
149 
150  /* Loopend if provided. Otherwise number of samples again */
151  if (ast->loopend && ast->loopstart >= 0) {
152  if (ast->loopend > samples) {
153  av_log(s, AV_LOG_WARNING, "Loopend value is out of range and will be ignored\n");
154  ast->loopend = samples;
155  }
156  avio_wb32(pb, ast->loopend);
157  } else {
158  avio_wb32(pb, samples);
159  }
160 
161  /* Size of first block */
162  avio_wb32(pb, ast->fbs);
163 
164  /* File size minus header */
165  avio_seek(pb, ast->size, SEEK_SET);
166  avio_wb32(pb, file_size - 64);
167 
168  /* Loop flag */
169  if (ast->loopstart >= 0) {
170  avio_skip(pb, 6);
171  avio_wb16(pb, 0xFFFF);
172  }
173 
174  avio_seek(pb, file_size, SEEK_SET);
175  }
176  return 0;
177 }
178 
179 #define OFFSET(obj) offsetof(ASTMuxContext, obj)
180 static const AVOption options[] = {
181  { "loopstart", "Loopstart position in milliseconds.", OFFSET(loopstart), AV_OPT_TYPE_INT64, { .i64 = -1 }, -1, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM },
182  { "loopend", "Loopend position in milliseconds.", OFFSET(loopend), AV_OPT_TYPE_INT64, { .i64 = 0 }, 0, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM },
183  { NULL },
184 };
185 
186 static const AVClass ast_muxer_class = {
187  .class_name = "AST muxer",
188  .item_name = av_default_item_name,
189  .option = options,
190  .version = LIBAVUTIL_VERSION_INT,
191 };
192 
194  .p.name = "ast",
195  .p.long_name = NULL_IF_CONFIG_SMALL("AST (Audio Stream)"),
196  .p.extensions = "ast",
197  .priv_data_size = sizeof(ASTMuxContext),
198  .p.audio_codec = AV_CODEC_ID_PCM_S16BE_PLANAR,
199  .p.video_codec = AV_CODEC_ID_NONE,
200  .p.subtitle_codec = AV_CODEC_ID_NONE,
201  .flags_internal = FF_OFMT_FLAG_MAX_ONE_OF_EACH,
202  .write_header = ast_write_header,
203  .write_packet = ast_write_packet,
204  .write_trailer = ast_write_trailer,
205  .p.priv_class = &ast_muxer_class,
206  .p.codec_tag = ff_ast_codec_tags_list,
207 };
OFFSET
#define OFFSET(obj)
Definition: astenc.c:179
AV_LOG_WARNING
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:186
AVOutputFormat::name
const char * name
Definition: avformat.h:510
AVERROR
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
opt.h
ffio_wfourcc
static av_always_inline void ffio_wfourcc(AVIOContext *pb, const uint8_t *s)
Definition: avio_internal.h:124
ASTMuxContext::fbs
int fbs
Definition: astenc.c:36
ast_write_trailer
static int ast_write_trailer(AVFormatContext *s)
Definition: astenc.c:122
AVCodecParameters
This struct describes the properties of an encoded stream.
Definition: codec_par.h:47
ASTMuxContext::size
int64_t size
Definition: astenc.c:32
AVPacket::data
uint8_t * data
Definition: packet.h:524
AV_CODEC_ID_PCM_S16BE_PLANAR
@ AV_CODEC_ID_PCM_S16BE_PLANAR
Definition: codec_id.h:358
AVOption
AVOption.
Definition: opt.h:357
mathematics.h
AVChannelLayout::nb_channels
int nb_channels
Number of channels in this layout.
Definition: channel_layout.h:313
FFOutputFormat::p
AVOutputFormat p
The public AVOutputFormat.
Definition: mux.h:65
ast.h
avio_tell
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:494
pkt
AVPacket * pkt
Definition: movenc.c:60
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
ast_muxer_class
static const AVClass ast_muxer_class
Definition: astenc.c:186
s
#define s(width, name)
Definition: cbs_vp9.c:198
AV_CODEC_ID_ADPCM_AFC
@ AV_CODEC_ID_ADPCM_AFC
Definition: codec_id.h:398
ff_codec_ast_tags
const AVCodecTag ff_codec_ast_tags[]
Definition: ast.c:26
AV_OPT_TYPE_INT64
@ AV_OPT_TYPE_INT64
Definition: opt.h:246
AV_LOG_DEBUG
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:201
ASTMuxContext::loopstart
int64_t loopstart
Definition: astenc.c:34
options
static const AVOption options[]
Definition: astenc.c:180
AVFormatContext
Format I/O context.
Definition: avformat.h:1255
internal.h
LIBAVUTIL_VERSION_INT
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
NULL
#define NULL
Definition: coverity.c:32
AVERROR_PATCHWELCOME
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:64
av_default_item_name
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:237
ASTMuxContext::samples
int64_t samples
Definition: astenc.c:33
FFOutputFormat
Definition: mux.h:61
ffio_fill
void ffio_fill(AVIOContext *s, int b, int64_t count)
Definition: aviobuf.c:187
AVCodecParameters::ch_layout
AVChannelLayout ch_layout
Audio only.
Definition: codec_par.h:180
AV_OPT_FLAG_ENCODING_PARAM
#define AV_OPT_FLAG_ENCODING_PARAM
A generic parameter which can be set by the user for muxing or encoding.
Definition: opt.h:280
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:184
ASTMuxContext::loopend
int64_t loopend
Definition: astenc.c:35
AVIOContext
Bytestream IO Context.
Definition: avio.h:160
AVPacket::size
int size
Definition: packet.h:525
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:94
size
int size
Definition: twinvq_data.h:10344
avio_write
void avio_write(AVIOContext *s, const unsigned char *buf, int size)
Definition: aviobuf.c:201
avio_wb32
void avio_wb32(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:365
avio_wl32
void avio_wl32(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:357
ff_ast_muxer
const FFOutputFormat ff_ast_muxer
Definition: astenc.c:193
AV_CODEC_ID_NONE
@ AV_CODEC_ID_NONE
Definition: codec_id.h:50
avio_internal.h
AVCodecParameters::block_align
int block_align
Audio only.
Definition: codec_par.h:191
FF_OFMT_FLAG_MAX_ONE_OF_EACH
#define FF_OFMT_FLAG_MAX_ONE_OF_EACH
If this flag is set, it indicates that for each codec type whose corresponding default codec (i....
Definition: mux.h:50
ff_ast_codec_tags_list
const AVCodecTag *const ff_ast_codec_tags_list[]
Definition: ast.c:32
avio_seek
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:231
AVClass::class_name
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:71
avformat.h
AVIO_SEEKABLE_NORMAL
#define AVIO_SEEKABLE_NORMAL
Seeking works like for a local file.
Definition: avio.h:41
ff_codec_get_tag
unsigned int ff_codec_get_tag(const AVCodecTag *tags, enum AVCodecID id)
Definition: utils.c:123
samples
Filter the word “frame” indicates either a video frame or a group of audio samples
Definition: filter_design.txt:8
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:318
avio_wb64
void avio_wb64(AVIOContext *s, uint64_t val)
Definition: aviobuf.c:431
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:55
AVPacket
This structure stores compressed data.
Definition: packet.h:501
avio_wb16
void avio_wb16(AVIOContext *s, unsigned int val)
Definition: aviobuf.c:443
ast_write_header
static int ast_write_header(AVFormatContext *s)
Definition: astenc.c:48
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
ast_write_packet
static int ast_write_packet(AVFormatContext *s, AVPacket *pkt)
Definition: astenc.c:101
CHECK_LOOP
#define CHECK_LOOP(type)
Definition: astenc.c:39
mux.h
ASTMuxContext
Definition: astenc.c:30