kenmirrors/asterisk
1
0
Fork 0
mirror of https://github.com/asterisk/asterisk.git synced 2025-10-12 15:45:18 +00:00
Code Issues Packages Projects Releases Wiki Activity

Update support for SILK format.

Browse Source 
This commit adds scaffolding in order to support the SILK audio format
on calls. Roughly, this is what is added:

* Cached silk formats. One for each possible sample rate.
* ast_codec structures for each possible sample rate.
* RTP payload mappings for "SILK".

In addition, this change overhauls the res_format_attr_silk file in the
following ways:

* The "samplerate" attribute is scrapped. That's native to the format.
* There are far more checks to ensure that attributes have been
  allocated before attempting to reference them.
* We do not SDP fmtp lines for attributes set to 0.

These changes make way to be able to install a codec_silk module and
have it actually work. It also should allow for passthrough silk calls
in Asterisk.

Change-Id: Ieeb39c95a9fecc9246bcfd3c45a6c9b51c59380e
This commit is contained in:
Mark Michelson
2016-06-30 15:58:53 -05:00
parent 3cf33dd4e7
commit 273052f404
5 changed files with 134 additions and 31 deletions
Download Patch File Download Diff File Expand all files Collapse all files

64
res/res_format_attr_silk.c
View File

@@ -40,7 +40,6 @@ ASTERISK_REGISTER_FILE()
* \note The only attribute that affects compatibility here is the sample rate.
*/
struct silk_attr {
unsigned int samplerate;
unsigned int maxbitrate;
unsigned int dtx;
unsigned int fec;
@@ -54,10 +53,15 @@ static void silk_destroy(struct ast_format *format)
ast_free(attr);
}
static void attr_init(struct silk_attr *attr)
{
memset(attr, 0, sizeof(*attr));
}
static int silk_clone(const struct ast_format *src, struct ast_format *dst)
{
struct silk_attr *original = ast_format_get_attribute_data(src);
struct silk_attr *attr = ast_calloc(1, sizeof(*attr));
struct silk_attr *attr = ast_malloc(sizeof(*attr));
if (!attr) {
return -1;
@@ -65,6 +69,8 @@ static int silk_clone(const struct ast_format *src, struct ast_format *dst)
if (original) {
*attr = *original;
} else {
attr_init(attr);
}
ast_format_set_attribute_data(dst, attr);
@@ -109,17 +115,17 @@ static void silk_generate_sdp_fmtp(const struct ast_format *format, unsigned int
ast_str_append(str, 0, "a=fmtp:%u maxaveragebitrate=%u\r\n", payload, attr->maxbitrate);
}
ast_str_append(str, 0, "a=fmtp:%u usedtx=%u\r\n", payload, attr->dtx);
ast_str_append(str, 0, "a=fmtp:%u useinbandfec=%u\r\n", payload, attr->fec);
if (attr->dtx) {
ast_str_append(str, 0, "a=fmtp:%u usedtx=%u\r\n", payload, attr->dtx);
}
if (attr->fec) {
ast_str_append(str, 0, "a=fmtp:%u useinbandfec=%u\r\n", payload, attr->fec);
}
}
static enum ast_format_cmp_res silk_cmp(const struct ast_format *format1, const struct ast_format *format2)
{
struct silk_attr *attr1 = ast_format_get_attribute_data(format1);
struct silk_attr *attr2 = ast_format_get_attribute_data(format2);
if (((!attr1 || !attr1->samplerate) && (!attr2 || !attr2->samplerate)) ||
(attr1->samplerate == attr2->samplerate)) {
if (ast_format_get_sample_rate(format1) == ast_format_get_sample_rate(format2)) {
return AST_FORMAT_CMP_EQUAL;
}
@@ -130,13 +136,10 @@ static struct ast_format *silk_getjoint(const struct ast_format *format1, const
{
struct silk_attr *attr1 = ast_format_get_attribute_data(format1);
struct silk_attr *attr2 = ast_format_get_attribute_data(format2);
unsigned int samplerate;
struct ast_format *jointformat;
struct silk_attr *attr_res;
samplerate = attr1->samplerate & attr2->samplerate;
/* sample rate is the only attribute that has any bearing on if joint capabilities exist or not */
if (samplerate) {
if (ast_format_get_sample_rate(format1) != ast_format_get_sample_rate(format2)) {
return NULL;
}
@@ -145,22 +148,25 @@ static struct ast_format *silk_getjoint(const struct ast_format *format1, const
return NULL;
}
attr_res = ast_format_get_attribute_data(jointformat);
attr_res->samplerate = samplerate;
/* Take the lowest max bitrate */
attr_res->maxbitrate = MIN(attr1->maxbitrate, attr2->maxbitrate);
if (!attr1 || !attr2) {
attr_init(attr_res);
} else {
/* Take the lowest max bitrate */
attr_res->maxbitrate = MIN(attr1->maxbitrate, attr2->maxbitrate);
/* Only do dtx if both sides want it. DTX is a trade off between
* computational complexity and bandwidth. */
attr_res->dtx = attr1->dtx && attr2->dtx ? 1 : 0;
/* Only do dtx if both sides want it. DTX is a trade off between
* computational complexity and bandwidth. */
attr_res->dtx = attr1->dtx && attr2->dtx ? 1 : 0;
/* Only do FEC if both sides want it. If a peer specifically requests not
* to receive with FEC, it may be a waste of bandwidth. */
attr_res->fec = attr1->fec && attr2->fec ? 1 : 0;
/* Only do FEC if both sides want it. If a peer specifically requests not
* to receive with FEC, it may be a waste of bandwidth. */
attr_res->fec = attr1->fec && attr2->fec ? 1 : 0;
/* Use the maximum packetloss percentage between the two attributes. This affects how
* much redundancy is used in the FEC. */
attr_res->packetloss_percentage = MAX(attr1->packetloss_percentage, attr2->packetloss_percentage);
/* Use the maximum packetloss percentage between the two attributes. This affects how
* much redundancy is used in the FEC. */
attr_res->packetloss_percentage = MAX(attr1->packetloss_percentage, attr2->packetloss_percentage);
}
return jointformat;
}
@@ -183,9 +189,7 @@ static struct ast_format *silk_set(const struct ast_format *format, const char *
}
attr = ast_format_get_attribute_data(cloned);
if (!strcasecmp(name, "sample_rate")) {
attr->samplerate = val;
} else if (!strcasecmp(name, "max_bitrate")) {
if (!strcasecmp(name, "max_bitrate")) {
attr->maxbitrate = val;
} else if (!strcasecmp(name, "dtx")) {
attr->dtx = val;
@@ -205,9 +209,7 @@ static const void *silk_get(const struct ast_format *format, const char *name)
struct silk_attr *attr = ast_format_get_attribute_data(format);
unsigned int *val;
if (!strcasecmp(name, "sample_rate")) {
val = &attr->samplerate;
} else if (!strcasecmp(name, "max_bitrate")) {
if (!strcasecmp(name, "max_bitrate")) {
val = &attr->maxbitrate;
} else if (!strcasecmp(name, "dtx")) {
val = &attr->dtx;