Asterisk - The Open Source Telephony Project  GIT-master-0190e70
format_h264.c
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1 /*
2  * Asterisk -- An open source telephony toolkit.
3  *
4  * Copyright (C) 1999 - 2005, Digium, Inc.
5  *
6  * Mark Spencer <markster@digium.com>
7  *
8  * See http://www.asterisk.org for more information about
9  * the Asterisk project. Please do not directly contact
10  * any of the maintainers of this project for assistance;
11  * the project provides a web site, mailing lists and IRC
12  * channels for your use.
13  *
14  * This program is free software, distributed under the terms of
15  * the GNU General Public License Version 2. See the LICENSE file
16  * at the top of the source tree.
17  */
18 
19 /*! \file
20  *
21  * \brief Save to raw, headerless h264 data.
22  * \arg File name extension: h264
23  * \ingroup formats
24  * \arg See \ref AstVideo
25  */
26 
27 /*** MODULEINFO
28  <support_level>core</support_level>
29  ***/
30 
31 #include "asterisk.h"
32 
33 #include "asterisk/mod_format.h"
34 #include "asterisk/module.h"
35 #include "asterisk/endian.h"
36 #include "asterisk/format_cache.h"
37 
38 /* Some Ideas for this code came from makeh264e.c by Jeffrey Chilton */
39 
40 /* Portions of the conversion code are by guido@sienanet.it */
41 /*! \todo Check this buf size estimate, it may be totally wrong for large frame video */
42 
43 #define FRAME_ENDED 0x8000
44 
45 #define BUF_SIZE 4096 /* Two Real h264 Frames */
46 struct h264_desc {
47  unsigned int lastts;
48 };
49 
50 static int h264_open(struct ast_filestream *s)
51 {
52  unsigned int ts;
53  if (fread(&ts, 1, sizeof(ts), s->f) != sizeof(ts)) {
54  ast_log(LOG_WARNING, "Empty file!\n");
55  return -1;
56  }
57  return 0;
58 }
59 
60 static struct ast_frame *h264_read(struct ast_filestream *s, int *whennext)
61 {
62  size_t res;
63  int mark = 0;
64  unsigned short len;
65  unsigned int ts;
66  struct h264_desc *fs = (struct h264_desc *)s->_private;
67 
68  /* Send a frame from the file to the appropriate channel */
69  if ((res = fread(&len, 1, sizeof(len), s->f)) != sizeof(len))
70  return NULL;
71  len = ntohs(len);
72  mark = (len & FRAME_ENDED) ? 1 : 0;
73  len &= 0x7fff;
74  if (len > BUF_SIZE) {
75  ast_log(LOG_WARNING, "Length %d is too long\n", len);
76  len = BUF_SIZE; /* XXX truncate */
77  }
79  if ((res = fread(s->fr.data.ptr, 1, s->fr.datalen, s->f)) != s->fr.datalen) {
80  if (res) {
81  ast_log(LOG_WARNING, "Short read of %s data (expected %d bytes, read %zu): %s\n",
83  strerror(errno));
84  }
85  return NULL;
86  }
87  s->fr.samples = fs->lastts;
88  s->fr.datalen = len;
89  s->fr.subclass.frame_ending = mark;
90  if ((res = fread(&ts, 1, sizeof(ts), s->f)) == sizeof(ts)) {
91  fs->lastts = ntohl(ts);
92  *whennext = fs->lastts * 4/45;
93  } else
94  *whennext = 0;
95  return &s->fr;
96 }
97 
98 static int h264_write(struct ast_filestream *s, struct ast_frame *f)
99 {
100  int res;
101  unsigned int ts;
102  unsigned short len;
103  int mark;
104 
105  mark = f->subclass.frame_ending ? FRAME_ENDED : 0;
106  ts = htonl(f->samples);
107  if ((res = fwrite(&ts, 1, sizeof(ts), s->f)) != sizeof(ts)) {
108  ast_log(LOG_WARNING, "Bad write (%d/4): %s\n", res, strerror(errno));
109  return -1;
110  }
111  len = htons(f->datalen | mark);
112  if ((res = fwrite(&len, 1, sizeof(len), s->f)) != sizeof(len)) {
113  ast_log(LOG_WARNING, "Bad write (%d/2): %s\n", res, strerror(errno));
114  return -1;
115  }
116  if ((res = fwrite(f->data.ptr, 1, f->datalen, s->f)) != f->datalen) {
117  ast_log(LOG_WARNING, "Bad write (%d/%d): %s\n", res, f->datalen, strerror(errno));
118  return -1;
119  }
120  return 0;
121 }
122 
123 static int h264_seek(struct ast_filestream *fs, off_t sample_offset, int whence)
124 {
125  /* No way Jose */
126  return -1;
127 }
128 
129 static int h264_trunc(struct ast_filestream *fs)
130 {
131  int fd;
132  off_t cur;
133 
134  if ((fd = fileno(fs->f)) < 0) {
135  ast_log(AST_LOG_WARNING, "Unable to determine file descriptor for h264 filestream %p: %s\n", fs, strerror(errno));
136  return -1;
137  }
138  if ((cur = ftello(fs->f)) < 0) {
139  ast_log(AST_LOG_WARNING, "Unable to determine current position in h264 filestream %p: %s\n", fs, strerror(errno));
140  return -1;
141  }
142  /* Truncate file to current length */
143  return ftruncate(fd, cur);
144 }
145 
146 static off_t h264_tell(struct ast_filestream *fs)
147 {
148  off_t offset = ftell(fs->f);
149  return offset; /* XXX totally bogus, needs fixing */
150 }
151 
152 static struct ast_format_def h264_f = {
153  .name = "h264",
154  .exts = "h264",
155  .open = h264_open,
156  .write = h264_write,
157  .seek = h264_seek,
158  .trunc = h264_trunc,
159  .tell = h264_tell,
160  .read = h264_read,
161  .buf_size = BUF_SIZE + AST_FRIENDLY_OFFSET,
162  .desc_size = sizeof(struct h264_desc),
163 };
164 
165 static int load_module(void)
166 {
167  h264_f.format = ast_format_h264;
168  if (ast_format_def_register(&h264_f))
171 }
172 
173 static int unload_module(void)
174 {
175  return ast_format_def_unregister(h264_f.name);
176 }
177 
179  .support_level = AST_MODULE_SUPPORT_CORE,
180  .load = load_module,
181  .unload = unload_module,
182  .load_pri = AST_MODPRI_APP_DEPEND
183 );
Asterisk main include file. File version handling, generic pbx functions.
#define BUF_SIZE
Definition: format_h264.c:45
#define LOG_WARNING
Definition: logger.h:274
union ast_frame::@257 data
static struct ast_frame * h264_read(struct ast_filestream *s, int *whennext)
Definition: format_h264.c:60
#define AST_LOG_WARNING
Definition: logger.h:279
static int load_module(void)
Definition: format_h264.c:165
if(!yyg->yy_init)
Definition: ast_expr2f.c:868
static int unload_module(void)
Definition: format_h264.c:173
const char * ast_format_get_name(const struct ast_format *format)
Get the name associated with a format.
Definition: format.c:334
static off_t h264_tell(struct ast_filestream *fs)
Definition: format_h264.c:146
#define NULL
Definition: resample.c:96
Each supported file format is described by the following structure.
Definition: mod_format.h:43
struct ast_frame_subclass subclass
Header for providers of file and format handling routines. Clients of these routines should include "...
int ast_format_def_unregister(const char *name)
Unregisters a file format.
Definition: file.c:162
#define ast_log
Definition: astobj2.c:42
#define AST_FRIENDLY_OFFSET
Offset into a frame&#39;s data buffer.
Asterisk architecture endianess compatibility definitions.
#define ast_format_def_register(f)
Definition: mod_format.h:136
struct ast_frame fr
frame produced by read, typically
Definition: mod_format.h:122
#define FRAME_ENDED
Definition: format_h264.c:43
struct ast_format * format
Definition: mod_format.h:48
static int h264_open(struct ast_filestream *s)
Definition: format_h264.c:50
void * _private
Definition: mod_format.h:124
#define AST_FRAME_SET_BUFFER(fr, _base, _ofs, _datalen)
static int len(struct ast_channel *chan, const char *cmd, char *data, char *buf, size_t buflen)
int errno
struct ast_format * ast_format_h264
Built-in cached h264 format.
Definition: format_cache.c:181
char name[80]
Definition: mod_format.h:44
static int h264_write(struct ast_filestream *s, struct ast_frame *f)
Definition: format_h264.c:98
unsigned int lastts
Definition: format_h264.c:47
Module has failed to load, may be in an inconsistent state.
Definition: module.h:78
AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_GLOBAL_SYMBOLS|AST_MODFLAG_LOAD_ORDER, "HTTP Phone Provisioning",.support_level=AST_MODULE_SUPPORT_EXTENDED,.load=load_module,.unload=unload_module,.reload=reload,.load_pri=AST_MODPRI_CHANNEL_DEPEND,.requires="http",)
This structure is allocated by file.c in one chunk, together with buf_size and desc_size bytes of mem...
Definition: mod_format.h:101
static int h264_seek(struct ast_filestream *fs, off_t sample_offset, int whence)
Definition: format_h264.c:123
Data structure associated with a single frame of data.
struct ast_format * format
#define ASTERISK_GPL_KEY
The text the key() function should return.
Definition: module.h:46
static struct ast_format_def h264_f
Definition: format_h264.c:152
Asterisk module definitions.
static int h264_trunc(struct ast_filestream *fs)
Definition: format_h264.c:129
Media Format Cache API.