Multi-party software based channel mixing. More...
#include "asterisk.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/time.h>
#include <signal.h>
#include <errno.h>
#include <unistd.h>
#include "asterisk/module.h"
#include "asterisk/channel.h"
#include "asterisk/bridging.h"
#include "asterisk/bridging_technology.h"
#include "asterisk/frame.h"
#include "asterisk/options.h"
#include "asterisk/logger.h"
#include "asterisk/slinfactory.h"
#include "asterisk/astobj2.h"
#include "asterisk/timing.h"
Go to the source code of this file.
Data Structures | |
struct | softmix_channel |
Define used to turn on 16 kHz audio support. More... | |
Defines | |
#define | SOFTMIX_DATALEN (160 * (SOFTMIX_INTERVAL / 10)) |
Size of the buffer used for sample manipulation. | |
#define | SOFTMIX_INTERVAL 20 |
Interval at which mixing will take place. Valid options are 10, 20, and 40. | |
#define | SOFTMIX_SAMPLES (SOFTMIX_DATALEN / 2) |
Number of samples we are dealing with. | |
Functions | |
AST_MODULE_INFO_STANDARD (ASTERISK_GPL_KEY,"Multi-party software based channel mixing") | |
static int | load_module (void) |
static int | softmix_bridge_create (struct ast_bridge *bridge) |
Function called when a bridge is created. | |
static int | softmix_bridge_destroy (struct ast_bridge *bridge) |
Function called when a bridge is destroyed. | |
static int | softmix_bridge_join (struct ast_bridge *bridge, struct ast_bridge_channel *bridge_channel) |
Function called when a channel is joined into the bridge. | |
static int | softmix_bridge_leave (struct ast_bridge *bridge, struct ast_bridge_channel *bridge_channel) |
Function called when a channel leaves the bridge. | |
static int | softmix_bridge_poke (struct ast_bridge *bridge, struct ast_bridge_channel *bridge_channel) |
Function called when the channel's thread is poked. | |
static int | softmix_bridge_thread (struct ast_bridge *bridge) |
Function which acts as the mixing thread. | |
static enum ast_bridge_write_result | softmix_bridge_write (struct ast_bridge *bridge, struct ast_bridge_channel *bridge_channel, struct ast_frame *frame) |
Function called when a channel writes a frame into the bridge. | |
static int | unload_module (void) |
Variables | |
static struct ast_bridge_technology | softmix_bridge |
Multi-party software based channel mixing.
Definition in file bridge_softmix.c.
#define SOFTMIX_DATALEN (160 * (SOFTMIX_INTERVAL / 10)) |
Size of the buffer used for sample manipulation.
Definition at line 63 of file bridge_softmix.c.
Referenced by softmix_bridge_join(), and softmix_bridge_thread().
#define SOFTMIX_INTERVAL 20 |
Interval at which mixing will take place. Valid options are 10, 20, and 40.
Definition at line 60 of file bridge_softmix.c.
Referenced by softmix_bridge_thread().
#define SOFTMIX_SAMPLES (SOFTMIX_DATALEN / 2) |
Number of samples we are dealing with.
Definition at line 66 of file bridge_softmix.c.
Referenced by softmix_bridge_join(), and softmix_bridge_thread().
AST_MODULE_INFO_STANDARD | ( | ASTERISK_GPL_KEY | , | |
"Multi-party software based channel mixing" | ||||
) |
static int load_module | ( | void | ) | [static] |
Definition at line 317 of file bridge_softmix.c.
References ast_bridge_technology_register.
00318 { 00319 return ast_bridge_technology_register(&softmix_bridge); 00320 }
static int softmix_bridge_create | ( | struct ast_bridge * | bridge | ) | [static] |
Function called when a bridge is created.
Definition at line 90 of file bridge_softmix.c.
References ast_timer_open(), ast_bridge::bridge_pvt, and timer.
00091 { 00092 struct ast_timer *timer; 00093 00094 if (!(timer = ast_timer_open())) { 00095 return -1; 00096 } 00097 00098 bridge->bridge_pvt = timer; 00099 00100 return 0; 00101 }
static int softmix_bridge_destroy | ( | struct ast_bridge * | bridge | ) | [static] |
Function called when a bridge is destroyed.
Definition at line 104 of file bridge_softmix.c.
References ast_timer_close(), and ast_bridge::bridge_pvt.
00105 { 00106 if (!bridge->bridge_pvt) { 00107 return -1; 00108 } 00109 ast_timer_close((struct ast_timer *) bridge->bridge_pvt); 00110 bridge->bridge_pvt = NULL; 00111 return 0; 00112 }
static int softmix_bridge_join | ( | struct ast_bridge * | bridge, | |
struct ast_bridge_channel * | bridge_channel | |||
) | [static] |
Function called when a channel is joined into the bridge.
Definition at line 115 of file bridge_softmix.c.
References ast_calloc, AST_FORMAT_SLINEAR, AST_FORMAT_SLINEAR16, AST_FRAME_VOICE, ast_mutex_init, ast_slinfactory_init(), ast_bridge_channel::bridge_pvt, ast_frame_subclass::codec, ast_frame::data, ast_frame::datalen, softmix_channel::factory, softmix_channel::final_buf, softmix_channel::frame, ast_frame::frametype, softmix_channel::lock, ast_frame::ptr, ast_frame::samples, SOFTMIX_DATALEN, SOFTMIX_SAMPLES, and ast_frame::subclass.
00116 { 00117 struct softmix_channel *sc = NULL; 00118 00119 /* Create a new softmix_channel structure and allocate various things on it */ 00120 if (!(sc = ast_calloc(1, sizeof(*sc)))) { 00121 return -1; 00122 } 00123 00124 /* Can't forget the lock */ 00125 ast_mutex_init(&sc->lock); 00126 00127 /* Setup smoother */ 00128 ast_slinfactory_init(&sc->factory); 00129 00130 /* Setup frame parameters */ 00131 sc->frame.frametype = AST_FRAME_VOICE; 00132 #ifdef SOFTMIX_16_SUPPORT 00133 sc->frame.subclass.codec = AST_FORMAT_SLINEAR16; 00134 #else 00135 sc->frame.subclass.codec = AST_FORMAT_SLINEAR; 00136 #endif 00137 sc->frame.data.ptr = sc->final_buf; 00138 sc->frame.datalen = SOFTMIX_DATALEN; 00139 sc->frame.samples = SOFTMIX_SAMPLES; 00140 00141 /* Can't forget to record our pvt structure within the bridged channel structure */ 00142 bridge_channel->bridge_pvt = sc; 00143 00144 return 0; 00145 }
static int softmix_bridge_leave | ( | struct ast_bridge * | bridge, | |
struct ast_bridge_channel * | bridge_channel | |||
) | [static] |
Function called when a channel leaves the bridge.
Definition at line 148 of file bridge_softmix.c.
References ast_free, ast_mutex_destroy, ast_slinfactory_destroy(), ast_bridge_channel::bridge_pvt, softmix_channel::factory, and softmix_channel::lock.
00149 { 00150 struct softmix_channel *sc = bridge_channel->bridge_pvt; 00151 00152 if (!(bridge_channel->bridge_pvt)) { 00153 return 0; 00154 } 00155 bridge_channel->bridge_pvt = NULL; 00156 00157 /* Drop mutex lock */ 00158 ast_mutex_destroy(&sc->lock); 00159 00160 /* Drop the factory */ 00161 ast_slinfactory_destroy(&sc->factory); 00162 00163 /* Eep! drop ourselves */ 00164 ast_free(sc); 00165 00166 return 0; 00167 }
static int softmix_bridge_poke | ( | struct ast_bridge * | bridge, | |
struct ast_bridge_channel * | bridge_channel | |||
) | [static] |
Function called when the channel's thread is poked.
Definition at line 203 of file bridge_softmix.c.
References ast_mutex_lock, ast_mutex_unlock, ast_write(), ast_bridge_channel::bridge_pvt, ast_bridge_channel::chan, softmix_channel::frame, softmix_channel::have_frame, and softmix_channel::lock.
00204 { 00205 struct softmix_channel *sc = bridge_channel->bridge_pvt; 00206 00207 ast_mutex_lock(&sc->lock); 00208 00209 if (sc->have_frame) { 00210 ast_write(bridge_channel->chan, &sc->frame); 00211 sc->have_frame = 0; 00212 } 00213 00214 ast_mutex_unlock(&sc->lock); 00215 00216 return 0; 00217 }
static int softmix_bridge_thread | ( | struct ast_bridge * | bridge | ) | [static] |
Function which acts as the mixing thread.
Definition at line 220 of file bridge_softmix.c.
References ao2_lock, ao2_unlock, ast_bridge::array_num, AST_LIST_TRAVERSE, ast_log(), ast_mutex_lock, ast_mutex_unlock, ast_slinear_saturated_add(), ast_slinear_saturated_subtract(), ast_slinfactory_available(), ast_slinfactory_read(), ast_timer_ack(), ast_timer_fd(), ast_timer_set_rate(), ast_waitfor_n_fd(), ast_bridge_channel::bridge_pvt, ast_bridge::bridge_pvt, softmix_channel::factory, softmix_channel::final_buf, softmix_channel::have_audio, softmix_channel::have_frame, softmix_channel::lock, LOG_ERROR, softmix_channel::our_buf, ast_bridge::refresh, SOFTMIX_DATALEN, SOFTMIX_INTERVAL, SOFTMIX_SAMPLES, ast_bridge::stop, ast_bridge_channel::thread, and timer.
00221 { 00222 struct ast_timer *timer = (struct ast_timer *) bridge->bridge_pvt; 00223 int timingfd = ast_timer_fd(timer); 00224 00225 ast_timer_set_rate(timer, (1000 / SOFTMIX_INTERVAL)); 00226 00227 while (!bridge->stop && !bridge->refresh && bridge->array_num) { 00228 struct ast_bridge_channel *bridge_channel = NULL; 00229 short buf[SOFTMIX_DATALEN] = {0, }; 00230 int timeout = -1; 00231 00232 /* Go through pulling audio from each factory that has it available */ 00233 AST_LIST_TRAVERSE(&bridge->channels, bridge_channel, entry) { 00234 struct softmix_channel *sc = bridge_channel->bridge_pvt; 00235 00236 ast_mutex_lock(&sc->lock); 00237 00238 /* Try to get audio from the factory if available */ 00239 if (ast_slinfactory_available(&sc->factory) >= SOFTMIX_SAMPLES && ast_slinfactory_read(&sc->factory, sc->our_buf, SOFTMIX_SAMPLES)) { 00240 short *data1, *data2; 00241 int i; 00242 00243 /* Put into the local final buffer */ 00244 for (i = 0, data1 = buf, data2 = sc->our_buf; i < SOFTMIX_DATALEN; i++, data1++, data2++) 00245 ast_slinear_saturated_add(data1, data2); 00246 /* Yay we have our own audio */ 00247 sc->have_audio = 1; 00248 } else { 00249 /* Awww we don't have audio ;( */ 00250 sc->have_audio = 0; 00251 } 00252 ast_mutex_unlock(&sc->lock); 00253 } 00254 00255 /* Next step go through removing the channel's own audio and creating a good frame... */ 00256 AST_LIST_TRAVERSE(&bridge->channels, bridge_channel, entry) { 00257 struct softmix_channel *sc = bridge_channel->bridge_pvt; 00258 int i = 0; 00259 00260 /* Copy from local final buffer to our final buffer */ 00261 memcpy(sc->final_buf, buf, sizeof(sc->final_buf)); 00262 00263 /* If we provided audio then take it out */ 00264 if (sc->have_audio) { 00265 for (i = 0; i < SOFTMIX_DATALEN; i++) { 00266 ast_slinear_saturated_subtract(&sc->final_buf[i], &sc->our_buf[i]); 00267 } 00268 } 00269 00270 /* The frame is now ready for use... */ 00271 sc->have_frame = 1; 00272 00273 /* Poke bridged channel thread just in case */ 00274 pthread_kill(bridge_channel->thread, SIGURG); 00275 } 00276 00277 ao2_unlock(bridge); 00278 00279 /* Wait for the timing source to tell us to wake up and get things done */ 00280 ast_waitfor_n_fd(&timingfd, 1, &timeout, NULL); 00281 00282 if (ast_timer_ack(timer, 1) < 0) { 00283 ast_log(LOG_ERROR, "Failed to acknowledge timer in softmix bridge\n"); 00284 ao2_lock(bridge); 00285 break; 00286 } 00287 00288 ao2_lock(bridge); 00289 } 00290 00291 return 0; 00292 }
static enum ast_bridge_write_result softmix_bridge_write | ( | struct ast_bridge * | bridge, | |
struct ast_bridge_channel * | bridge_channel, | |||
struct ast_frame * | frame | |||
) | [static] |
Function called when a channel writes a frame into the bridge.
Definition at line 170 of file bridge_softmix.c.
References AST_BRIDGE_WRITE_SUCCESS, AST_BRIDGE_WRITE_UNSUPPORTED, AST_FORMAT_SLINEAR, AST_FORMAT_SLINEAR16, AST_FRAME_VOICE, ast_mutex_lock, ast_mutex_unlock, ast_slinfactory_feed(), ast_write(), ast_bridge_channel::bridge_pvt, ast_bridge_channel::chan, ast_frame_subclass::codec, softmix_channel::factory, softmix_channel::frame, ast_frame::frametype, softmix_channel::have_frame, softmix_channel::lock, and ast_frame::subclass.
00171 { 00172 struct softmix_channel *sc = bridge_channel->bridge_pvt; 00173 00174 /* Only accept audio frames, all others are unsupported */ 00175 if (frame->frametype != AST_FRAME_VOICE) { 00176 return AST_BRIDGE_WRITE_UNSUPPORTED; 00177 } 00178 00179 ast_mutex_lock(&sc->lock); 00180 00181 /* If a frame was provided add it to the smoother */ 00182 #ifdef SOFTMIX_16_SUPPORT 00183 if (frame->frametype == AST_FRAME_VOICE && frame->subclass.codec == AST_FORMAT_SLINEAR16) { 00184 #else 00185 if (frame->frametype == AST_FRAME_VOICE && frame->subclass.codec == AST_FORMAT_SLINEAR) { 00186 #endif 00187 ast_slinfactory_feed(&sc->factory, frame); 00188 } 00189 00190 /* If a frame is ready to be written out, do so */ 00191 if (sc->have_frame) { 00192 ast_write(bridge_channel->chan, &sc->frame); 00193 sc->have_frame = 0; 00194 } 00195 00196 /* Alllll done */ 00197 ast_mutex_unlock(&sc->lock); 00198 00199 return AST_BRIDGE_WRITE_SUCCESS; 00200 }
static int unload_module | ( | void | ) | [static] |
Definition at line 312 of file bridge_softmix.c.
References ast_bridge_technology_unregister().
00313 { 00314 return ast_bridge_technology_unregister(&softmix_bridge); 00315 }
struct ast_bridge_technology softmix_bridge [static] |
Definition at line 294 of file bridge_softmix.c.