New HD ConfBridge conferencing application.

Includes a new highly optimized and customizable
ConfBridge application capable of mixing audio at
sample rates ranging from 8khz-192khz.

Review: https://reviewboard.asterisk.org/r/1147/



git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@314598 65c4cc65-6c06-0410-ace0-fbb531ad65f3

include/asterisk/bridging.h

@@ -63,6 +63,7 @@ extern "C" {
 #endif
 
 #include "asterisk/bridging_features.h"
+#include "asterisk/dsp.h"
 
 /*! \brief Capabilities for a bridge technology */
 enum ast_bridge_capability {
@@ -96,6 +97,10 @@ enum ast_bridge_channel_state {
 	AST_BRIDGE_CHANNEL_STATE_FEATURE,
 	/*! Bridged channel is sending a DTMF stream out */
 	AST_BRIDGE_CHANNEL_STATE_DTMF,
+	/*! Bridged channel began talking */
+	AST_BRIDGE_CHANNEL_STATE_START_TALKING,
+	/*! Bridged channel has stopped talking */
+	AST_BRIDGE_CHANNEL_STATE_STOP_TALKING,
 };
 
 /*! \brief Return values for bridge technology write function */
@@ -111,6 +116,22 @@ enum ast_bridge_write_result {
 struct ast_bridge_technology;
 struct ast_bridge;
 
+/*!
+ * \brief Structure specific to bridge technologies capable of
+ * performing talking optimizations.
+ */
+struct ast_bridge_tech_optimizations {
+	/*! The amount of time in ms that talking must be detected before
+	 *  the dsp determines that talking has occurred */
+	unsigned int talking_threshold;
+	/*! The amount of time in ms that silence must be detected before
+	 *  the dsp determines that talking has stopped */
+	unsigned int silence_threshold;
+	/*! Whether or not the bridging technology should drop audio
+	 *  detected as silence from the mix. */
+	unsigned int drop_silence:1;
+};
+
 /*!
  * \brief Structure that contains information regarding a channel in a bridge
  */
@@ -137,6 +158,9 @@ struct ast_bridge_channel {
 	unsigned int suspended:1;
 	/*! Features structure for features that are specific to this channel */
 	struct ast_bridge_features *features;
+	/*! Technology optimization parameters used by bridging technologies capable of
+	 *  optimizing based upon talk detection. */
+	struct ast_bridge_tech_optimizations tech_args;
 	/*! Queue of DTMF digits used for DTMF streaming */
 	char dtmf_stream_q[8];
 	/*! Linked list information */
@@ -149,6 +173,13 @@ struct ast_bridge_channel {
 struct ast_bridge {
 	/*! Number of channels participating in the bridge */
 	int num;
+	/*! The internal sample rate this bridge is mixed at when multiple channels are being mixed.
+	 *  If this value is 0, the bridge technology may auto adjust the internal mixing rate. */
+	unsigned int internal_sample_rate;
+	/*! The mixing interval indicates how quickly the bridges internal mixing should occur
+	 * for bridge technologies that mix audio. When set to 0, the bridge tech must choose a
+	 * default interval for itself. */
+	unsigned int internal_mixing_interval;
 	/*! Bit to indicate that the bridge thread is waiting on channels in the bridge array */
 	unsigned int waiting:1;
 	/*! Bit to indicate the bridge thread should stop */
@@ -236,6 +267,7 @@ int ast_bridge_destroy(struct ast_bridge *bridge);
  * \param chan Channel to join
  * \param swap Channel to swap out if swapping
  * \param features Bridge features structure
+ * \param (Optional) Bridging tech optimization parameters for this channel.
  *
  * \retval state that channel exited the bridge with
  *
@@ -256,7 +288,11 @@ int ast_bridge_destroy(struct ast_bridge *bridge);
  * If channel specific features are enabled a pointer to the features structure
  * can be specified in the features parameter.
  */
-enum ast_bridge_channel_state ast_bridge_join(struct ast_bridge *bridge, struct ast_channel *chan, struct ast_channel *swap, struct ast_bridge_features *features);
+enum ast_bridge_channel_state ast_bridge_join(struct ast_bridge *bridge,
+	struct ast_channel *chan,
+	struct ast_channel *swap,
+	struct ast_bridge_features *features,
+	struct ast_bridge_tech_optimizations *tech_args);
 
 /*! \brief Impart (non-blocking) a channel on a bridge
  *
@@ -419,6 +455,27 @@ int ast_bridge_unsuspend(struct ast_bridge *bridge, struct ast_channel *chan);
  */
 void ast_bridge_change_state(struct ast_bridge_channel *bridge_channel, enum ast_bridge_channel_state new_state);
 
+/*! \brief Adjust the internal mixing sample rate of a bridge used during
+ *         multimix mode.
+ *
+ * \param bridge_channel Channel to change the sample rate on.
+ * \param sample rate, the sample rate to change to. If a
+ *        value of 0 is passed here, the bridge will be free to pick
+ *        what ever sample rate it chooses.
+ *
+ */
+void ast_bridge_set_internal_sample_rate(struct ast_bridge *bridge, unsigned int sample_rate);
+
+/*! \brief Adjust the internal mixing interval of a bridge used during
+ *         multimix mode.
+ *
+ * \param bridge_channel Channel to change the sample rate on.
+ * \param mixing_interval, the sample rate to change to.  If 0 is set
+ * the bridge tech is free to choose any mixing interval it uses by default.
+ */
+void ast_bridge_set_mixing_interval(struct ast_bridge *bridge, unsigned int mixing_interval);
+
+
 #if defined(__cplusplus) || defined(c_plusplus)
 }
 #endif

include/asterisk/bridging_features.h

@@ -63,6 +63,31 @@ struct ast_bridge_channel;
  */
 typedef int (*ast_bridge_features_hook_callback)(struct ast_bridge *bridge, struct ast_bridge_channel *bridge_channel, void *hook_pvt);
 
+/*!
+ * \brief Features hook pvt destructor callback
+ *
+ * \param hook_pvt Private data passed in when the hook was create to destroy
+ */
+typedef void (*ast_bridge_features_hook_pvt_destructor)(void *hook_pvt);
+
+/*!
+ * \brief Talking indicator callback
+ *
+ * \details This callback can be registered with the bridge in order
+ * to receive updates on when a bridge_channel has started and stopped
+ * talking
+ *
+ * \param bridge The bridge that the channel is part of
+ * \param bridge_channel Channel executing the feature
+ *
+ * \retval 0 success
+ * \retval -1 failure
+ */
+typedef void (*ast_bridge_talking_indicate_callback)(struct ast_bridge *bridge, struct ast_bridge_channel *bridge_channel, void *pvt_data);
+
+
+typedef void (*ast_bridge_talking_indicate_destructor)(void *pvt_data);
+
 /*!
  * \brief Maximum length of a DTMF feature string
  */
@@ -76,6 +101,8 @@ struct ast_bridge_features_hook {
 	char dtmf[MAXIMUM_DTMF_FEATURE_STRING];
 	/*! Callback that is called when DTMF string is matched */
 	ast_bridge_features_hook_callback callback;
+	/*! Callback to destroy hook_pvt data right before destruction. */
+	ast_bridge_features_hook_pvt_destructor destructor;
 	/*! Unique data that was passed into us */
 	void *hook_pvt;
 	/*! Linked list information */
@@ -88,12 +115,21 @@ struct ast_bridge_features_hook {
 struct ast_bridge_features {
 	/*! Attached DTMF based feature hooks */
 	AST_LIST_HEAD_NOLOCK(, ast_bridge_features_hook) hooks;
+	/*! Callback to indicate when a bridge channel has started and stopped talking */
+	ast_bridge_talking_indicate_callback talker_cb;
+	/*! Callback to destroy any pvt data stored for the talker. */
+	ast_bridge_talking_indicate_destructor talker_destructor_cb;
+	/*! Talker callback pvt data */
+	void *talker_pvt_data;
 	/*! Feature flags that are enabled */
 	struct ast_flags feature_flags;
-	/*! Bit to indicate that this structure is useful and should be considered when looking for features */
+	/*! Bit to indicate that the hook list is useful and should be considered when looking for DTMF features */
 	unsigned int usable:1;
 	/*! Bit to indicate whether the channel/bridge is muted or not */
 	unsigned int mute:1;
+	/*! Bit to indicate whether DTMF should be passed into the bridge tech or not.  */
+	unsigned int dtmf_passthrough:1;
+
 };
 
 /*!
@@ -161,6 +197,7 @@ int ast_bridge_features_unregister(enum ast_bridge_builtin_feature feature);
  * \param dtmf DTMF string to be activated upon
  * \param callback Function to execute upon activation
  * \param hook_pvt Unique data
+ * \param Optional destructor callback for hook_pvt data
  *
  * \retval 0 on success
  * \retval -1 on failure
@@ -170,7 +207,7 @@ int ast_bridge_features_unregister(enum ast_bridge_builtin_feature feature);
  * \code
  * struct ast_bridge_features features;
  * ast_bridge_features_init(&features);
- * ast_bridge_features_hook(&features, "#", pound_callback, NULL);
+ * ast_bridge_features_hook(&features, "#", pound_callback, NULL, NULL);
  * \endcode
  *
  * This makes the bridging core call pound_callback if a channel that has this
@@ -180,7 +217,26 @@ int ast_bridge_features_unregister(enum ast_bridge_builtin_feature feature);
  * \note It is important that the callback set the bridge channel state back to
  *       AST_BRIDGE_CHANNEL_STATE_WAIT or the bridge thread will not service the channel.
  */
-int ast_bridge_features_hook(struct ast_bridge_features *features, const char *dtmf, ast_bridge_features_hook_callback callback, void *hook_pvt);
+int ast_bridge_features_hook(struct ast_bridge_features *features,
+	const char *dtmf,
+	ast_bridge_features_hook_callback callback,
+	void *hook_pvt,
+	ast_bridge_features_hook_pvt_destructor destructor);
+
+/*! \brief Set a callback on the features structure to receive talking notifications on.
+ *
+ * \param features Bridge features structure
+ * \param talker_cb, Callback function to execute when talking events occur in the bridge core.
+ * \param pvt_data Optional unique data that will be passed with the talking events.
+ * \param Optional destructor callback for pvt data.
+ *
+ * \retval 0, success
+ * \retval -1, failure
+ */
+int ast_bridge_features_set_talk_detector(struct ast_bridge_features *features,
+	ast_bridge_talking_indicate_callback talker_cb,
+	ast_bridge_talking_indicate_destructor talker_destructor,
+	void *pvt_data);
 
 /*! \brief Enable a built in feature on a bridge features structure
  *

include/asterisk/bridging_technology.h

@@ -143,6 +143,21 @@ int ast_bridge_technology_unregister(struct ast_bridge_technology *technology);
  */
 void ast_bridge_handle_trip(struct ast_bridge *bridge, struct ast_bridge_channel *bridge_channel, struct ast_channel *chan, int outfd);
 
+/*! \brief Lets the bridging indicate when a bridge channel has stopped or started talking.
+ *
+ * \note All DSP functionality on the bridge has been pushed down to the lowest possible
+ * layer, which in this case is the specific bridging technology being used. Since it
+ * is necessary for the knowledge of which channels are talking to make its way up to the
+ * application, this function has been created to allow the bridging technology to communicate
+ * that information with the bridging core.
+ *
+ * \param bridge The bridge that the channel is a part of.
+ * \param bridge_channel The bridge channel that has either started or stopped talking.
+ * \param started_talking, set to 1 when this indicates the channel has started talking, set to 0
+ * when this indicates the channel has stopped talking.
+ */
+void ast_bridge_notify_talking(struct ast_bridge *bridge, struct ast_bridge_channel *bridge_channel, int started_talking);
+
 /*! \brief Suspend a bridge technology from consideration
  *
  * \param technology The bridge technology to suspend

include/asterisk/channel.h

@@ -178,6 +178,7 @@ typedef unsigned long long ast_group_t;
 */
 struct ast_generator {
 	void *(*alloc)(struct ast_channel *chan, void *params);
+	/*! Channel is locked during this function callback. */
 	void (*release)(struct ast_channel *chan, void *data);
 	/*! This function gets called with the channel unlocked, but is called in
 	 *  the context of the channel thread so we know the channel is not going
@@ -186,6 +187,9 @@ struct ast_generator {
 	int (*generate)(struct ast_channel *chan, void *data, int len, int samples);
 	/*! This gets called when DTMF_END frames are read from the channel */
 	void (*digit)(struct ast_channel *chan, char digit);
+	/*! This gets called when the write format on a channel is changed while
+	 * generating. The channel is locked during this callback. */
+	void (*write_format_change)(struct ast_channel *chan, void *data);
 };
 
 /*! Party name character set enumeration values (values from Q.SIG) */

include/asterisk/dsp.h

@@ -73,9 +73,19 @@ enum threshold {
 	THRESHOLD_MAX = 1,
 };
 
+/*! \brief Allocates a new dsp with a specific internal sample rate used
+ * during processing. */
+struct ast_dsp *ast_dsp_new_with_rate(unsigned int sample_rate);
+
+/*! \brief Allocates a new dsp, assumes 8khz for internal sample rate */
 struct ast_dsp *ast_dsp_new(void);
+
 void ast_dsp_free(struct ast_dsp *dsp);
 
+/*! \brief Retrieve the sample rate this DSP structure was
+ * created with */
+unsigned int ast_dsp_get_sample_rate(const struct ast_dsp *dsp);
+
 /*! \brief Set threshold value for silence */
 void ast_dsp_set_threshold(struct ast_dsp *dsp, int threshold);