struct pjmedia_frame *output);} pjmedia_codec_op;/* * Forward declaration for pjmedia_codec_factory. */typedef struct pjmedia_codec_factory pjmedia_codec_factory;/** * This structure describes a codec instance.  */struct pjmedia_codec{    /** Entries to put this codec instance in codec factory's list. */    PJ_DECL_LIST_MEMBER(struct pjmedia_codec);    /** Codec's private data. */    void		    *codec_data;    /** Codec factory where this codec was allocated. */    pjmedia_codec_factory   *factory;    /** Operations to codec. */    pjmedia_codec_op	    *op;};/** * This structure describes operations that must be supported by codec  * factories. */typedef struct pjmedia_codec_factory_op{    /**      * Check whether the factory can create codec with the specified      * codec info.     *     * @param factory	The codec factory.     * @param info	The codec info.     *     * @return		PJ_SUCCESS if this factory is able to create an     *			instance of codec with the specified info.     */    pj_status_t	(*test_alloc)(pjmedia_codec_factory *factory, 			      const pjmedia_codec_info *info );    /**      * Create default attributes for the specified codec ID. This function     * can be called by application to get the capability of the codec.     *     * @param factory	The codec factory.     * @param info	The codec info.     * @param attr	The attribute to be initialized.     *     * @return		PJ_SUCCESS if success.     */    pj_status_t (*default_attr)(pjmedia_codec_factory *factory,     				const pjmedia_codec_info *info,    				pjmedia_codec_param *attr );    /**      * Enumerate supported codecs that can be created using this factory.     *      *  @param factory	The codec factory.     *  @param count	On input, specifies the number of elements in     *			the array. On output, the value will be set to     *			the number of elements that have been initialized     *			by this function.     *  @param info	The codec info array, which contents will be      *			initialized upon return.     *     *  @return		PJ_SUCCESS on success.     */    pj_status_t (*enum_info)(pjmedia_codec_factory *factory, 			     unsigned *count, 			     pjmedia_codec_info codecs[]);    /**      * Create one instance of the codec with the specified codec info.     *     * @param factory	The codec factory.     * @param info	The codec info.     * @param p_codec	Pointer to receive the codec instance.     *     * @return		PJ_SUCCESS on success.     */    pj_status_t (*alloc_codec)(pjmedia_codec_factory *factory, 			       const pjmedia_codec_info *info,			       pjmedia_codec **p_codec);    /**      * This function is called by codec manager to return a particular      * instance of codec back to the codec factory.     *     * @param factory	The codec factory.     * @param codec	The codec instance to be returned.     *     * @return		PJ_SUCCESS on success.     */    pj_status_t (*dealloc_codec)(pjmedia_codec_factory *factory, 				 pjmedia_codec *codec );} pjmedia_codec_factory_op;/** * Codec factory describes a module that is able to create codec with specific * capabilities. These capabilities can be queried by codec manager to create * instances of codec. */struct pjmedia_codec_factory{    /** Entries to put this structure in the codec manager list. */    PJ_DECL_LIST_MEMBER(struct pjmedia_codec_factory);    /** The factory's private data. */    void		     *factory_data;    /** Operations to the factory. */    pjmedia_codec_factory_op *op;};/** * Declare maximum codecs */#define PJMEDIA_CODEC_MGR_MAX_CODECS	    32/** * Specify these values to set the codec priority, by calling * #pjmedia_codec_mgr_set_codec_priority(). */typedef enum pjmedia_codec_priority{    /**     * This priority makes the codec the highest in the order.     * The last codec specified with this priority will get the     * highest place in the order, and will change the priority     * of previously highest priority codec to NEXT_HIGHER.     */    PJMEDIA_CODEC_PRIO_HIGHEST = 255,    /**     * This priority will put the codec as the next codec after     * codecs with this same priority.     */    PJMEDIA_CODEC_PRIO_NEXT_HIGHER = 254,    /**     * This is the initial codec priority when it is registered to     * codec manager by codec factory.     */    PJMEDIA_CODEC_PRIO_NORMAL = 128,    /**     * This priority makes the codec the lowest in the order.     * The last codec specified with this priority will be put     * in the last place in the order.     */    PJMEDIA_CODEC_PRIO_LOWEST = 1,    /**     * This priority will prevent the codec from being listed in the     * SDP created by media endpoint, thus should prevent the codec     * from being used in the sessions. However, the codec will still     * be listed by #pjmedia_codec_mgr_enum_codecs() and other codec     * query functions.     */    PJMEDIA_CODEC_PRIO_DISABLED = 0} pjmedia_codec_priority;/**  * Codec identification (e.g. "pcmu/8000/1"). * See @ref codec_ident for more info. */typedef char pjmedia_codec_id[32];/**  * Codec manager maintains array of these structs for each supported * codec. */struct pjmedia_codec_desc{    pjmedia_codec_info	    info;	/**< Codec info.	    */    pjmedia_codec_id	    id;		/**< Fully qualified name   */    pjmedia_codec_priority  prio;	/**< Priority.		    */    pjmedia_codec_factory  *factory;	/**< The factory.	    */};/** * The declaration for codec manager. Application doesn't normally need * to see this declaration, but nevertheless this declaration is needed * by media endpoint to instantiate the codec manager. */typedef struct pjmedia_codec_mgr{    /** List of codec factories registered to codec manager. */    pjmedia_codec_factory	factory_list;    /** Number of supported codesc. */    unsigned			codec_cnt;    /** Array of codec descriptor. */    struct pjmedia_codec_desc	codec_desc[PJMEDIA_CODEC_MGR_MAX_CODECS];} pjmedia_codec_mgr;/** * Initialize codec manager. Normally this function is called by pjmedia * endpoint's initialization code. * * @param mgr	    Codec manager instance. * * @return	    PJ_SUCCESS on success. */PJ_DECL(pj_status_t) pjmedia_codec_mgr_init(pjmedia_codec_mgr *mgr);/**  * Register codec factory to codec manager. This will also register * all supported codecs in the factory to the codec manager. * * @param mgr	    The codec manager instance. Application can get the *		    instance by calling #pjmedia_endpt_get_codec_mgr(). * @param factory   The codec factory to be registered. * * @return	    PJ_SUCCESS on success. */PJ_DECL(pj_status_t) pjmedia_codec_mgr_register_factory( pjmedia_codec_mgr *mgr,				    pjmedia_codec_factory *factory);/** * Unregister codec factory from the codec manager. This will also * remove all the codecs registered by the codec factory from the * codec manager's list of supported codecs. * * @param mgr	    The codec manager instance. Application can get the *		    instance by calling #pjmedia_endpt_get_codec_mgr(). * @param factory   The codec factory to be unregistered. * * @return	    PJ_SUCCESS on success. */PJ_DECL(pj_status_t) pjmedia_codec_mgr_unregister_factory( pjmedia_codec_mgr *mgr, 				      pjmedia_codec_factory *factory);/** * Enumerate all supported codecs that have been registered to the * codec manager by codec factories. * * @param mgr	    The codec manager instance. Application can get the *		    instance by calling #pjmedia_endpt_get_codec_mgr(). * @param count	    On input, specifies the number of elements in *		    the array. On output, the value will be set to *		    the number of elements that have been initialized *		    by this function. * @param info	    The codec info array, which contents will be  *		    initialized upon return. * @param prio	    Optional pointer to receive array of codec priorities. * * @return	    PJ_SUCCESS on success. */PJ_DECL(pj_status_t) pjmedia_codec_mgr_enum_codecs( pjmedia_codec_mgr *mgr, 						    unsigned *count, 						    pjmedia_codec_info info[],						    unsigned *prio);/** * Get codec info for the specified static payload type. Note that * this can only find codec with static payload types. This function can * be used to find codec info for a payload type inside SDP which doesn't * have the corresponding rtpmap attribute. * * @param mgr	    The codec manager instance. Application can get the *		    instance by calling #pjmedia_endpt_get_codec_mgr(). * @param pt	    Static payload type/number. * @param inf	    Pointer to receive codec info. * * @return	    PJ_SUCCESS on success. */PJ_DECL(pj_status_t) pjmedia_codec_mgr_get_codec_info( pjmedia_codec_mgr *mgr,				  unsigned pt,				  const pjmedia_codec_info **inf);/** * Convert codec info struct into a unique codec identifier. * A codec identifier looks something like "L16/44100/2". * * @param info	    The codec info * @param id	    Buffer to put the codec info string. * @param max_len   The length of the buffer. * * @return	    The null terminated codec info string, or NULL if *		    the buffer is not long enough. */PJ_DECL(char*) pjmedia_codec_info_to_id(const pjmedia_codec_info *info,				        char *id, unsigned max_len );/** * Find codecs by the unique codec identifier. This function will find * all codecs that match the codec identifier prefix. For example, if * "L16" is specified, then it will find "L16/8000/1", "L16/16000/1", * and so on, up to the maximum count specified in the argument. * * @param mgr	    The codec manager instance. Application can get the *		    instance by calling #pjmedia_endpt_get_codec_mgr(). * @param codec_id  The full codec ID or codec ID prefix. If an empty *		    string is given, it will match all codecs. * @param count	    Maximum number of codecs to find. On return, it *		    contains the actual number of codecs found. * @param p_info    Array of pointer to codec info to be filled. This *		    argument may be NULL, which in this case, only *		    codec count will be returned. * @param prio	    Optional array of codec priorities. * * @return	    PJ_SUCCESS if at least one codec info is found. */PJ_DECL(pj_status_t) pjmedia_codec_mgr_find_codecs_by_id( pjmedia_codec_mgr *mgr,				     const pj_str_t *codec_id,				     unsigned *count,				     const pjmedia_codec_info *p_info[],				     unsigned prio[]);/** * Set codec priority. The codec priority determines the order of * the codec in the SDP created by the endpoint. If more than one codecs * are found with the same codec_id prefix, then the function sets the * priorities of all those codecs. * * @param mgr	    The codec manager instance. Application can get the *		    instance by calling #pjmedia_endpt_get_codec_mgr(). * @param codec_id  The full codec ID or codec ID prefix. If an empty *		    string is given, it will match all codecs. * @param prio	    Priority to be set. The priority can have any value *		    between 1 to 255. When the priority is set to zero, *		    the codec will be disabled. * * @return	    PJ_SUCCESS if at least one codec info is found. */PJ_DECL(pj_status_t)pjmedia_codec_mgr_set_codec_priority(pjmedia_codec_mgr *mgr, 				     const pj_str_t *codec_id,				     pj_uint8_t prio);/** * Get default codec param for the specified codec info. * * @param mgr	    The codec manager instance. Application can get the *		    instance by calling #pjmedia_endpt_get_codec_mgr(). * @param info	    The codec info, which default parameter's is being *		    queried. * @param param	    On return, will be filled with the default codec *		    parameter. * * @return	    PJ_SUCCESS on success. */PJ_DECL(pj_status_t) pjmedia_codec_mgr_get_default_param( pjmedia_codec_mgr *mgr,				     const pjmedia_codec_info *info,				     pjmedia_codec_param *param );/** * Request the codec manager to allocate one instance of codec with the * specified codec info. The codec will enumerate all codec factories * until it finds factory that is able to create the specified codec. * * @param mgr	    The codec manager instance. Application can get the *		    instance by calling #pjmedia_endpt_get_codec_mgr(). * @param info	    The information about the codec to be created. * @param p_codec   Pointer to receive the codec instance. * * @return	    PJ_SUCCESS on success. */PJ_DECL(pj_status_t) pjmedia_codec_mgr_alloc_codec( pjmedia_codec_mgr *mgr, 			       const pjmedia_codec_info *info,			       pjmedia_codec **p_codec);/** * Deallocate the specified codec instance. The codec manager will return * the instance of the codec back to its factory. * * @param mgr	    The codec manager instance. Application can get the *		    instance by calling #pjmedia_endpt_get_codec_mgr(). * @param codec	    The codec instance. * * @return	    PJ_SUCESS on success. */PJ_DECL(pj_status_t) pjmedia_codec_mgr_dealloc_codec(pjmedia_codec_mgr *mgr, 						     pjmedia_codec *codec);/** * @} */PJ_END_DECL#endif	/* __PJMEDIA_CODEC_H__ */