diff options
Diffstat (limited to 'trunk/formats/format_g726.c')
-rw-r--r-- | trunk/formats/format_g726.c | 261 |
1 files changed, 261 insertions, 0 deletions
diff --git a/trunk/formats/format_g726.c b/trunk/formats/format_g726.c new file mode 100644 index 000000000..e27476fed --- /dev/null +++ b/trunk/formats/format_g726.c @@ -0,0 +1,261 @@ +/* + * Asterisk -- An open source telephony toolkit. + * + * Copyright (c) 2004 - 2005, inAccess Networks + * + * Michael Manousos <manousos@inaccessnetworks.com> + * + * See http://www.asterisk.org for more information about + * the Asterisk project. Please do not directly contact + * any of the maintainers of this project for assistance; + * the project provides a web site, mailing lists and IRC + * channels for your use. + * + * This program is free software, distributed under the terms of + * the GNU General Public License Version 2. See the LICENSE file + * at the top of the source tree. + */ + +/*!\file + * + * \brief Headerless G.726 (16/24/32/40kbps) data format for Asterisk. + * + * File name extensions: + * \arg 40 kbps: g726-40 + * \arg 32 kbps: g726-32 + * \arg 24 kbps: g726-24 + * \arg 16 kbps: g726-16 + * \ingroup formats + */ + +#include "asterisk.h" + +ASTERISK_FILE_VERSION(__FILE__, "$Revision$") + +#include "asterisk/mod_format.h" +#include "asterisk/module.h" +#include "asterisk/endian.h" + +#define RATE_40 0 +#define RATE_32 1 +#define RATE_24 2 +#define RATE_16 3 + +/* We can only read/write chunks of FRAME_TIME ms G.726 data */ +#define FRAME_TIME 10 /* 10 ms size */ + +#define BUF_SIZE (5*FRAME_TIME) /* max frame size in bytes ? */ +/* Frame sizes in bytes */ +static int frame_size[4] = { + FRAME_TIME * 5, + FRAME_TIME * 4, + FRAME_TIME * 3, + FRAME_TIME * 2 +}; + +struct g726_desc { + int rate; /* RATE_* defines */ +}; + +/* + * Rate dependant format functions (open, rewrite) + */ +static int g726_open(struct ast_filestream *tmp, int rate) +{ + struct g726_desc *s = (struct g726_desc *)tmp->_private; + s->rate = rate; + ast_debug(1, "Created filestream G.726-%dk.\n", 40 - s->rate * 8); + return 0; +} + +static int g726_40_open(struct ast_filestream *s) +{ + return g726_open(s, RATE_40); +} + +static int g726_32_open(struct ast_filestream *s) +{ + return g726_open(s, RATE_32); +} + +static int g726_24_open(struct ast_filestream *s) +{ + return g726_open(s, RATE_24); +} + +static int g726_16_open(struct ast_filestream *s) +{ + return g726_open(s, RATE_16); +} + +static int g726_40_rewrite(struct ast_filestream *s, const char *comment) +{ + return g726_open(s, RATE_40); +} + +static int g726_32_rewrite(struct ast_filestream *s, const char *comment) +{ + return g726_open(s, RATE_32); +} + +static int g726_24_rewrite(struct ast_filestream *s, const char *comment) +{ + return g726_open(s, RATE_24); +} + +static int g726_16_rewrite(struct ast_filestream *s, const char *comment) +{ + return g726_open(s, RATE_16); +} + +/* + * Rate independent format functions (read, write) + */ + +static struct ast_frame *g726_read(struct ast_filestream *s, int *whennext) +{ + int res; + struct g726_desc *fs = (struct g726_desc *)s->_private; + + /* Send a frame from the file to the appropriate channel */ + s->fr.frametype = AST_FRAME_VOICE; + s->fr.subclass = AST_FORMAT_G726; + s->fr.mallocd = 0; + AST_FRAME_SET_BUFFER(&s->fr, s->buf, AST_FRIENDLY_OFFSET, frame_size[fs->rate]); + s->fr.samples = 8 * FRAME_TIME; + if ((res = fread(s->fr.data, 1, s->fr.datalen, s->f)) != s->fr.datalen) { + if (res) + ast_log(LOG_WARNING, "Short read (%d) (%s)!\n", res, strerror(errno)); + return NULL; + } + *whennext = s->fr.samples; + return &s->fr; +} + +static int g726_write(struct ast_filestream *s, struct ast_frame *f) +{ + int res; + struct g726_desc *fs = (struct g726_desc *)s->_private; + + if (f->frametype != AST_FRAME_VOICE) { + ast_log(LOG_WARNING, "Asked to write non-voice frame!\n"); + return -1; + } + if (f->subclass != AST_FORMAT_G726) { + ast_log(LOG_WARNING, "Asked to write non-G726 frame (%d)!\n", + f->subclass); + return -1; + } + if (f->datalen % frame_size[fs->rate]) { + ast_log(LOG_WARNING, "Invalid data length %d, should be multiple of %d\n", + f->datalen, frame_size[fs->rate]); + return -1; + } + if ((res = fwrite(f->data, 1, f->datalen, s->f)) != f->datalen) { + ast_log(LOG_WARNING, "Bad write (%d/%d): %s\n", + res, frame_size[fs->rate], strerror(errno)); + return -1; + } + return 0; +} + +static int g726_seek(struct ast_filestream *fs, off_t sample_offset, int whence) +{ + return -1; +} + +static int g726_trunc(struct ast_filestream *fs) +{ + return -1; +} + +static off_t g726_tell(struct ast_filestream *fs) +{ + return -1; +} + +static const struct ast_format f[] = { + { + .name = "g726-40", + .exts = "g726-40", + .format = AST_FORMAT_G726, + .open = g726_40_open, + .rewrite = g726_40_rewrite, + .write = g726_write, + .seek = g726_seek, + .trunc = g726_trunc, + .tell = g726_tell, + .read = g726_read, + .buf_size = BUF_SIZE + AST_FRIENDLY_OFFSET, + .desc_size = sizeof(struct g726_desc), + }, + { + .name = "g726-32", + .exts = "g726-32", + .format = AST_FORMAT_G726, + .open = g726_32_open, + .rewrite = g726_32_rewrite, + .write = g726_write, + .seek = g726_seek, + .trunc = g726_trunc, + .tell = g726_tell, + .read = g726_read, + .buf_size = BUF_SIZE + AST_FRIENDLY_OFFSET, + .desc_size = sizeof(struct g726_desc), + }, + { + .name = "g726-24", + .exts = "g726-24", + .format = AST_FORMAT_G726, + .open = g726_24_open, + .rewrite = g726_24_rewrite, + .write = g726_write, + .seek = g726_seek, + .trunc = g726_trunc, + .tell = g726_tell, + .read = g726_read, + .buf_size = BUF_SIZE + AST_FRIENDLY_OFFSET, + .desc_size = sizeof(struct g726_desc), + }, + { + .name = "g726-16", + .exts = "g726-16", + .format = AST_FORMAT_G726, + .open = g726_16_open, + .rewrite = g726_16_rewrite, + .write = g726_write, + .seek = g726_seek, + .trunc = g726_trunc, + .tell = g726_tell, + .read = g726_read, + .buf_size = BUF_SIZE + AST_FRIENDLY_OFFSET, + .desc_size = sizeof(struct g726_desc), + }, + { .format = 0 } /* terminator */ +}; + +static int load_module(void) +{ + int i; + + for (i = 0; f[i].format ; i++) { + if (ast_format_register(&f[i])) { /* errors are fatal */ + ast_log(LOG_WARNING, "Failed to register format %s.\n", f[i].name); + return AST_MODULE_LOAD_FAILURE; + } + } + return AST_MODULE_LOAD_SUCCESS; +} + +static int unload_module(void) +{ + int i; + + for (i = 0; f[i].format ; i++) { + if (ast_format_unregister(f[i].name)) + ast_log(LOG_WARNING, "Failed to unregister format %s.\n", f[i].name); + } + return(0); +} + +AST_MODULE_INFO_STANDARD(ASTERISK_GPL_KEY, "Raw G.726 (16/24/32/40kbps) data"); |