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libvlc.h定义了libvlc的外部api，引用这个头文件就可以把VLC嵌入到我们的程序里面了。
/*****************************************************************************
* libvlc.h: libvlc external API
*****************************************************************************
* Copyright (C) 1998-2009 VLC authors and VideoLAN
* $Id: b12d900469fa6438c41421f2ac7697b93ffc8a35 $
*
* Authors: Clément Stenac <[email protected]>
* Jean-Paul Saman <[email protected]>
* Pierre d'Herbemont <[email protected]>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation; either version 2.1 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
*****************************************************************************/
/**
* \defgroup libvlc LibVLC
* LibVLC is the external programming interface of the VLC media player.
* It is used to embed VLC into other applications or frameworks.
* @{
* \file
* LibVLC core external API
*/
#ifndef VLC_LIBVLC_H
#define VLC_LIBVLC_H 1
#if defined (_WIN32) && defined (DLL_EXPORT)
# define LIBVLC_API __declspec(dllexport)
#elif defined (__GNUC__) && (__GNUC__ >= 4)
# define LIBVLC_API __attribute__((visibility("default")))
#else
# define LIBVLC_API
#endif
#ifdef __LIBVLC__
/* Avoid unhelpful warnings from libvlc with our deprecated APIs */
# define LIBVLC_DEPRECATED
#elif defined(__GNUC__) && \
(__GNUC__ > 3 || __GNUC__ == 3 && __GNUC_MINOR__ > 0)
# define LIBVLC_DEPRECATED __attribute__((deprecated))
#else
# define LIBVLC_DEPRECATED
#endif
#include <stdio.h>
#include <stdarg.h>
#include <stdint.h>
# ifdef __cplusplus
extern "C" {
# endif
/** \defgroup libvlc_core LibVLC core
* \ingroup libvlc
* Before it can do anything useful, LibVLC must be initialized.
* You can create one (or more) instance(s) of LibVLC in a given process,
* with libvlc_new() and destroy them with libvlc_release().
*
* \version Unless otherwise stated, these functions are available
* from LibVLC versions numbered 1.1.0 or more.
* Earlier versions (0.9.x and 1.0.x) are <b>not</b> compatible.
* @{
*/
/** This structure is opaque. It represents a libvlc instance */
typedef struct libvlc_instance_t libvlc_instance_t;
typedef int64_t libvlc_time_t;
/** \defgroup libvlc_error LibVLC error handling
* @{
*/
/**
* A human-readable error message for the last LibVLC error in the calling
* thread. The resulting string is valid until another error occurs (at least
* until the next LibVLC call).
*
* @warning
* This will be NULL if there was no error.
*/
LIBVLC_API const char *libvlc_errmsg (void);
/**
* Clears the LibVLC error status for the current thread. This is optional.
* By default, the error status is automatically overridden when a new error
* occurs, and destroyed when the thread exits.
*/
LIBVLC_API void libvlc_clearerr (void);
/**
* Sets the LibVLC error status and message for the current thread.
* Any previous error is overridden.
* \param fmt the format string
* \param ap the arguments
* \return a nul terminated string in any case
*/
LIBVLC_API const char *libvlc_vprinterr (const char *fmt, va_list ap);
/**
* Sets the LibVLC error status and message for the current thread.
* Any previous error is overridden.
* \param fmt the format string
* \param args the arguments
* \return a nul terminated string in any case
*/
LIBVLC_API const char *libvlc_printerr (const char *fmt, ...);
/**@} */
/**
* Create and initialize a libvlc instance.
* This functions accept a list of "command line" arguments similar to the
* main(). These arguments affect the LibVLC instance default configuration.
*
* \note
* LibVLC may create threads. Therefore, any thread-unsafe process
* initialization must be performed before calling libvlc_new(). In particular
* and where applicable:
* - setlocale() and textdomain(),
* - setenv(), unsetenv() and putenv(),
* - with the X11 display system, XInitThreads()
* (see also libvlc_media_player_set_xwindow()) and
* - on Microsoft Windows, SetErrorMode().
* - sigprocmask() shall never be invoked; pthread_sigmask() can be used.
*
* On POSIX systems, the SIGCHLD signal <b>must not</b> be ignored, i.e. the
* signal handler must set to SIG_DFL or a function pointer, not SIG_IGN.
* Also while LibVLC is active, the wait() function shall not be called, and
* any call to waitpid() shall use a strictly positive value for the first
* parameter (i.e. the PID). Failure to follow those rules may lead to a
* deadlock or a busy loop.
* Also on POSIX systems, it is recommended that the SIGPIPE signal be blocked,
* even if it is not, in principles, necessary, e.g.:
* @code
sigset_t set;
signal(SIGCHLD, SIG_DFL);
sigemptyset(&set);
sigaddset(&set, SIGPIPE);
pthread_sigmask(SIG_BLOCK, &set, NULL);
* @endcode
*
* On Microsoft Windows Vista/2008, the process error mode
* SEM_FAILCRITICALERRORS flag <b>must</b> be set before using LibVLC.
* On later versions, that is optional and unnecessary.
* Also on Microsoft Windows (Vista and any later version), setting the default
* DLL directories to SYSTEM32 exclusively is strongly recommended for
* security reasons:
* @code
SetErrorMode(SEM_FAILCRITICALERRORS);
SetDefaultDllDirectories(LOAD_LIBRARY_SEARCH_SYSTEM32);
* @endcode
*
* \version
* Arguments are meant to be passed from the command line to LibVLC, just like
* VLC media player does. The list of valid arguments depends on the LibVLC
* version, the operating system and platform, and set of available LibVLC
* plugins. Invalid or unsupported arguments will cause the function to fail
* (i.e. return NULL). Also, some arguments may alter the behaviour or
* otherwise interfere with other LibVLC functions.
*
* \warning
* There is absolutely no warranty or promise of forward, backward and
* cross-platform compatibility with regards to libvlc_new() arguments.
* We recommend that you do not use them, other than when debugging.
*
* \param argc the number of arguments (should be 0)
* \param argv list of arguments (should be NULL)
* \return the libvlc instance or NULL in case of error
*/
LIBVLC_API libvlc_instance_t *
libvlc_new( int argc , const char *const *argv );
/**
* Decrement the reference count of a libvlc instance, and destroy it
* if it reaches zero.
*
* \param p_instance the instance to destroy
*/
LIBVLC_API void libvlc_release( libvlc_instance_t *p_instance );
/**
* Increments the reference count of a libvlc instance.
* The initial reference count is 1 after libvlc_new() returns.
*
* \param p_instance the instance to reference
*/
LIBVLC_API void libvlc_retain( libvlc_instance_t *p_instance );
/**
* Try to start a user interface for the libvlc instance.
*
* \param p_instance the instance
* \param name interface name, or NULL for default
* \return 0 on success, -1 on error.
*/
LIBVLC_API
int libvlc_add_intf( libvlc_instance_t *p_instance, const char *name );
/**
* Registers a callback for the LibVLC exit event. This is mostly useful if
* the VLC playlist and/or at least one interface are started with
* libvlc_playlist_play() or libvlc_add_intf() respectively.
* Typically, this function will wake up your application main loop (from
* another thread).
*
* \note This function should be called before the playlist or interface are
* started. Otherwise, there is a small race condition: the exit event could
* be raised before the handler is registered.
*
* \param p_instance LibVLC instance
* \param cb callback to invoke when LibVLC wants to exit,
* or NULL to disable the exit handler (as by default)
* \param opaque data pointer for the callback
* \warning This function and libvlc_wait() cannot be used at the same time.
*/
LIBVLC_API
void libvlc_set_exit_handler( libvlc_instance_t *p_instance,
void (*cb) (void *), void *opaque );
/**
* Sets the application name. LibVLC passes this as the user agent string
* when a protocol requires it.
*
* \param p_instance LibVLC instance
* \param name human-readable application name, e.g. "FooBar player 1.2.3"
* \param http HTTP User Agent, e.g. "FooBar/1.2.3 Python/2.6.0"
* \version LibVLC 1.1.1 or later
*/
LIBVLC_API
void libvlc_set_user_agent( libvlc_instance_t *p_instance,
const char *name, const char *http );
/**
* Sets some meta-information about the application.
* See also libvlc_set_user_agent().
*
* \param p_instance LibVLC instance
* \param id Java-style application identifier, e.g. "com.acme.foobar"
* \param version application version numbers, e.g. "1.2.3"
* \param icon application icon name, e.g. "foobar"
* \version LibVLC 2.1.0 or later.
*/
LIBVLC_API
void libvlc_set_app_id( libvlc_instance_t *p_instance, const char *id,
const char *version, const char *icon );
/**
* Retrieve libvlc version.
*
* Example: "1.1.0-git The Luggage"
*
* \return a string containing the libvlc version
*/
LIBVLC_API const char * libvlc_get_version(void);
/**
* Retrieve libvlc compiler version.
*
* Example: "gcc version 4.2.3 (Ubuntu 4.2.3-2ubuntu6)"
*
* \return a string containing the libvlc compiler version
*/
LIBVLC_API const char * libvlc_get_compiler(void);
/**
* Retrieve libvlc changeset.
*
* Example: "aa9bce0bc4"
*
* \return a string containing the libvlc changeset
*/
LIBVLC_API const char * libvlc_get_changeset(void);
/**
* Frees an heap allocation returned by a LibVLC function.
* If you know you're using the same underlying C run-time as the LibVLC
* implementation, then you can call ANSI C free() directly instead.
*
* \param ptr the pointer
*/
LIBVLC_API void libvlc_free( void *ptr );
/** \defgroup libvlc_event LibVLC asynchronous events
* LibVLC emits asynchronous events.
*
* Several LibVLC objects (such @ref libvlc_instance_t as
* @ref libvlc_media_player_t) generate events asynchronously. Each of them
* provides @ref libvlc_event_manager_t event manager. You can subscribe to
* events with libvlc_event_attach() and unsubscribe with
* libvlc_event_detach().
* @{
*/
/**
* Event manager that belongs to a libvlc object, and from whom events can
* be received.
*/
typedef struct libvlc_event_manager_t libvlc_event_manager_t;
struct libvlc_event_t;
/**
* Type of a LibVLC event.
*/
typedef int libvlc_event_type_t;
/**
* Callback function notification
* \param p_event the event triggering the callback
*/
typedef void ( *libvlc_callback_t )( const struct libvlc_event_t *p_event, void *p_data );
/**
* Register for an event notification.
*
* \param p_event_manager the event manager to which you want to attach to.
* Generally it is obtained by vlc_my_object_event_manager() where
* my_object is the object you want to listen to.
* \param i_event_type the desired event to which we want to listen
* \param f_callback the function to call when i_event_type occurs
* \param user_data user provided data to carry with the event
* \return 0 on success, ENOMEM on error
*/
LIBVLC_API int libvlc_event_attach( libvlc_event_manager_t *p_event_manager,
libvlc_event_type_t i_event_type,
libvlc_callback_t f_callback,
void *user_data );
/**
* Unregister an event notification.
*
* \param p_event_manager the event manager
* \param i_event_type the desired event to which we want to unregister
* \param f_callback the function to call when i_event_type occurs
* \param p_user_data user provided data to carry with the event
*/
LIBVLC_API void libvlc_event_detach( libvlc_event_manager_t *p_event_manager,
libvlc_event_type_t i_event_type,
libvlc_callback_t f_callback,
void *p_user_data );
/**
* Get an event's type name.
*
* \param event_type the desired event
*/
LIBVLC_API const char * libvlc_event_type_name( libvlc_event_type_t event_type );
/** @} */
/** \defgroup libvlc_log LibVLC logging
* libvlc_log_* functions provide access to the LibVLC messages log.
* This is used for logging and debugging.
* @{
*/
/**
* Logging messages level.
* \note Future LibVLC versions may define new levels.
*/
enum libvlc_log_level
{
LIBVLC_DEBUG=0, /**< Debug message */
LIBVLC_NOTICE=2, /**< Important informational message */
LIBVLC_WARNING=3, /**< Warning (potential error) message */
LIBVLC_ERROR=4 /**< Error message */
};
typedef struct vlc_log_t libvlc_log_t;
/**
* Gets log message debug infos.
*
* This function retrieves self-debug information about a log message:
* - the name of the VLC module emitting the message,
* - the name of the source code module (i.e. file) and
* - the line number within the source code module.
*
* The returned module name and file name will be NULL if unknown.
* The returned line number will similarly be zero if unknown.
*
* \param ctx message context (as passed to the @ref libvlc_log_cb callback)
* \param module module name storage (or NULL) [OUT]
* \param file source code file name storage (or NULL) [OUT]
* \param line source code file line number storage (or NULL) [OUT]
* \warning The returned module name and source code file name, if non-NULL,
* are only valid until the logging callback returns.
*
* \version LibVLC 2.1.0 or later
*/
LIBVLC_API void libvlc_log_get_context(const libvlc_log_t *ctx,
const char **module, const char **file, unsigned *line);
/**
* Gets log message info.
*
* This function retrieves meta-information about a log message:
* - the type name of the VLC object emitting the message,
* - the object header if any, and
* - a temporaly-unique object identifier.
*
* This information is mainly meant for <b>manual</b> troubleshooting.
*
* The returned type name may be "generic" if unknown, but it cannot be NULL.
* The returned header will be NULL if unset; in current versions, the header
* is used to distinguish for VLM inputs.
* The returned object ID will be zero if the message is not associated with
* any VLC object.
*
* \param ctx message context (as passed to the @ref libvlc_log_cb callback)
* \param name object name storage (or NULL) [OUT]
* \param header object header (or NULL) [OUT]
* \param line source code file line number storage (or NULL) [OUT]
* \warning The returned module name and source code file name, if non-NULL,
* are only valid until the logging callback returns.
*
* \version LibVLC 2.1.0 or later
*/
LIBVLC_API void libvlc_log_get_object(const libvlc_log_t *ctx,
const char **name, const char **header, uintptr_t *id);
/**
* Callback prototype for LibVLC log message handler.
*
* \param data data pointer as given to libvlc_log_set()
* \param level message level (@ref libvlc_log_level)
* \param ctx message context (meta-information about the message)
* \param fmt printf() format string (as defined by ISO C11)
* \param args variable argument list for the format
* \note Log message handlers <b>must</b> be thread-safe.
* \warning The message context pointer, the format string parameters and the
* variable arguments are only valid until the callback returns.
*/
typedef void (*libvlc_log_cb)(void *data, int level, const libvlc_log_t *ctx,
const char *fmt, va_list args);
/**
* Unsets the logging callback.
*
* This function deregisters the logging callback for a LibVLC instance.
* This is rarely needed as the callback is implicitly unset when the instance
* is destroyed.
*
* \note This function will wait for any pending callbacks invocation to
* complete (causing a deadlock if called from within the callback).
*
* \param p_instance libvlc instance
* \version LibVLC 2.1.0 or later
*/
LIBVLC_API void libvlc_log_unset( libvlc_instance_t *p_instance );
/**
* Sets the logging callback for a LibVLC instance.
*
* This function is thread-safe: it will wait for any pending callbacks
* invocation to complete.
*
* \param cb callback function pointer
* \param data opaque data pointer for the callback function
*
* \note Some log messages (especially debug) are emitted by LibVLC while
* is being initialized. These messages cannot be captured with this interface.
*
* \warning A deadlock may occur if this function is called from the callback.
*
* \param p_instance libvlc instance
* \version LibVLC 2.1.0 or later
*/
LIBVLC_API void libvlc_log_set( libvlc_instance_t *p_instance,
libvlc_log_cb cb, void *data );
/**
* Sets up logging to a file.
* \param p_instance libvlc instance
* \param stream FILE pointer opened for writing
* (the FILE pointer must remain valid until libvlc_log_unset())
* \version LibVLC 2.1.0 or later
*/
LIBVLC_API void libvlc_log_set_file( libvlc_instance_t *p_instance, FILE *stream );
/** @} */
/**
* Description of a module.
*/
typedef struct libvlc_module_description_t
{
char *psz_name;
char *psz_shortname;
char *psz_longname;
char *psz_help;
struct libvlc_module_description_t *p_next;
} libvlc_module_description_t;
/**
* Release a list of module descriptions.
*
* \param p_list the list to be released
*/
LIBVLC_API
void libvlc_module_description_list_release( libvlc_module_description_t *p_list );
/**
* Returns a list of audio filters that are available.
*
* \param p_instance libvlc instance
*
* \return a list of module descriptions. It should be freed with libvlc_module_description_list_release().
* In case of an error, NULL is returned.
*
* \see libvlc_module_description_t
* \see libvlc_module_description_list_release
*/
LIBVLC_API
libvlc_module_description_t *libvlc_audio_filter_list_get( libvlc_instance_t *p_instance );
/**
* Returns a list of video filters that are available.
*
* \param p_instance libvlc instance
*
* \return a list of module descriptions. It should be freed with libvlc_module_description_list_release().
* In case of an error, NULL is returned.
*
* \see libvlc_module_description_t
* \see libvlc_module_description_list_release
*/
LIBVLC_API
libvlc_module_description_t *libvlc_video_filter_list_get( libvlc_instance_t *p_instance );
/** @} */
/** \defgroup libvlc_clock LibVLC time
* These functions provide access to the LibVLC time/clock.
* @{
*/
/**
* Return the current time as defined by LibVLC. The unit is the microsecond.
* Time increases monotonically (regardless of time zone changes and RTC
* adjustements).
* The origin is arbitrary but consistent across the whole system
* (e.g. the system uptim, the time since the system was booted).
* \note On systems that support it, the POSIX monotonic clock is used.
*/
LIBVLC_API
int64_t libvlc_clock(void);
/**
* Return the delay (in microseconds) until a certain timestamp.
* \param pts timestamp
* \return negative if timestamp is in the past,
* positive if it is in the future
*/
static inline int64_t libvlc_delay(int64_t pts)
{
return pts - libvlc_clock();
}
/** @} */
# ifdef __cplusplus
}
# endif
#endif /** @} */
libvlc的对象必须先被初始化之后才能被使用。
libvlc core
| libvlc_new() | 用于初始化一个libvlc的实例，argc表示参数的个数，argv表示参数，返回创建的实例若当发生错误时返回NULL |
| libvlc_release() | 用于销毁一个libvlc的实例 |
libvlc error handing
| libvlc_errmsg() | 返回的是在当前线程中产生的最新的libvlc错误，这个错误信息至少在另外一个错误发生之前（至少再调用一次libvlc）都是有效的，当没有任何错误的时候返回的是NULL |
| libvlc_clearerr() | 用于清除当前线程的libvlc的错误状态.此操作是可选的,默认情况下,错误状态是会在新的错误发生时被覆盖. |
| libvlc_vprinterr | 用于设置当前线程的libvlc的错误状态和消息.无论何时都返回一个nul字符 |
| libvlc_printerr() | 源码里的注释和上一个一模一样 |
| libvlc_retain() | 增加libvlc的引用计数,任何新的libvlc实例的引用计数为1 |
| libvlc_add_intf() | 尝试启动libvlc实例的用户接口,p_instance表示要启动的实例,name为接口名,NULL表示默认,返回0表示成功-1表示发生错误 |
| libvlc_set_exits_handler() | 此函数用于为一个已存在的libvlc事件注册一个回调.此方法在你用libvlc_add_intf()开启了至少一个接口时非常有用.典型的,这个函数将唤醒你的程序主循环(从其他线程).参数p_instance 表示libvlc实例,cb表示当libvlc要退出时要调用的回调.opaque表示回调的数据指针.警告:此函数不能同libvlc_wait()同时调用. |
| libvlc_wait() | 等待到有一个接口引发实例的推出动作.必须先用libvlc_add_intf()开启至少一个接口. |
| libvlc_set_user_agent() | 设置应用程序名,当有协议要求的时候,libvlc将把这个名字作为用户代理串传递给它.参数name应该是一个可读的应用程序名,例如"FooBar player 1.2.3"，http参数为HTTP User Agent。例如"FooBar/1.2.3 Python/2.6.0。 |
| libvlc_get_Version() | 返回libvlc的版本号 |
| libvlc_get_compiler() | 返回编译libvlc的编译器的版本。 |
| libvlc_get_changeset() | 返回libvlc的 changeset |
libvlc asynchronous events libvlc 发出不同步事件
许多libvlc对象，如libvlc_instance_t libvlc_media_player_t不同步的产生时间，它们中的每一个都提供了libvlc_event_manager_t事件管理器。你可以通过libvlc_event_attach（）来订阅这些事件以及用libvlc_event_detach（）来退订事件。
| libvlc_event_manager_t | 是属于libvlc对象的事件管理器 |
| libvlc_event_type_t | 表示libvlc的事件 |
| libvlc_callback_t | 回调函数通知(call back function notification翻译不准确）,参数p_event为触发回调的时间. |
| libvlc_event_attach() | 注册一个event notification。参数p_event_manager 想要绑定的事件管理器.通常来说它是由vlc_my_object_event_manager()处获得的,此处的my_object是你想要监听的对象,i_event_type是想要监听的事件，f_callback是当i_event_type发生时要调用的函数。user_data是用户提供的伴随事件而传递的数据。成功时此函数返回0，发生错误时返回ENOMEM |
| libvlc_event_detach() | 退订一个event notification |
| libvlc_event_type_name() | 获得一个事件的类型名 |
libvlc_log LibVLC loggingvlc_log系列函数提供了访问libvlc消息日志的方法。这些函数仅用于高级用户或调试之用。
| libvlc_get_log_verbosity() | 获得VLC消息的详细级别 |
| libvlc_set_log_verbosity() | 设置VLC消息的详细级别 |
| libvlc_log_open() | 开启VLC消息日志实例(从一个libvlc实例中获得其消息日志实例) |
| libvlc_log_close() | 关闭VLC消息日志实例 |
| libvlc_log_count() | 返回日志中消息条数 |
| libvlc_log_clear() | 清除日志实例.将把实例中的所有消息删除,为了防止消息阻塞,应该经常清除. |
| libvlc_log_get_iterator() | 定位并返回一个日志中记录的iterator |
| libvlc_log_iterator_free() | 释放一个先前定位好的iterator |
| libvlc_log_itereator_next() | 返回下一条日志消息,当接下来为空的时候返回NULL,否则返回下一个消息对象 |
libvlc_media.h libvlc_media_t 是一个可播放的媒体的抽象表达，它包含了这个媒体的位置以及各种可选的元数据。
| libvlc_state_t | 此枚举类型的循序必须严格保证和源码一致 |
| libvlc_media_stats_t | Libvlc的媒体统计信息 |
| libvlc_media_track_info_t | 没有注释，主要是fourcc和docec的其他信息。 |
| libvlc_media_new_location() | 使用一个给定的媒体资源路径来建立一个libvlc_media对象.参数psz_mrl为要读取的MRL(Media Resource Location).此函数返回新建的对象或NULL. |
| libvlc_media_new_path() | 从本地文件系统路径新建,其他参照上一条 |
| libvlc_media_new_as_node() | 使用给定的名称创建一个libvlc_media_t并将其作为一个空的节点 |
| libvlc_media_add_option() | 添加一个选项到已有的libvlc_media_t,这个选项将被用于决定media_player如何读取媒体。这样一来就可以在每个媒体上指定各自的VLC的高级reading/streaming选项。 |
| libvlc_media_add_option_flag() | 添加一个带有可配置标记的选贤到已有的libvlc_media_t.其他同上一条. |
| libvlc_media_retain() | 保留一个引用到一个媒体描述对象(libvlc_media_t.使用libvlc_media_release()来减少一个媒体描述对象的引用计数 |
| libvlc_media_release() | 减少一个libvlc_media_t的引用计数,如果减少到0时,此此函数将释放此对象(销毁).它将发送一个libvlc_MediaFreed事件到所有的监听者那里。如果一个libvlc_media_t被释放了，它就再也不能使用了。 |
| libvlc_media_get_mrl() | 从一个媒体描述对象处获得它的mrl |
| libvlc_media_duplicate | 镜像一份媒体描述对象 |
| libvlc_media_get_meta() | 读取媒体的元数据。如果媒体还没被解析，则返回NULL，这个方法会自动调用libvlc_media_parse_async()，因此，在调用此方法以后，你可以接收到一个libvlc_MediaMetaChanged事件。如果你希望使用一个同步的版本，请确保你在调用get_meta()之前调用了libvlc_media_parse(); |
| libvlc_media_set_meta() | 设置媒体的元数据,此方法不会保存数据,还需要调用libvlc_media_save_meta()来保存. |
| libvlc_media_get_state() | 获取当前媒体描述对象的状态.可能的状态被定义在livblc_structures.c中. |
| libvlc_media_subitems() | 获得一个媒体描述对象的子项目.此方法将增加媒体描述对象的引用计数,使用libvlc_media_list_release()减少引用计数. |
| libvlc_media_event_manager() | 获得一个媒体描述对象的事件管理器. |
| libvlc_media_get_duration | 获得一个媒体描述对象的持续时间.发生错误时返回-1. |
| libvlc_media_parse() | 解析一个本地媒体的元数据和轨道信息,此方法是同步的. |
| libvlc_media_parse_async() | 同上,此方法不同步,你可以监听libvlc_MediaParsedChanged事件来追踪他，如果已经被解析过了则此事件不会被触发。 |
| libvlc_media_is_parsed() | 获得一个媒体描述对象的分析状态。当分析过了返回true。 |
| libvlc_media_set_user_data() | 设置媒体描述符的用户数据,此数据仅被host程序访问,VLC.framework将它作为一个指向一个引用了一个libvlc_media_t指针的本地对象的指针来使用 |
| libvlc_media_get_tracks-info() | 获得媒体描述符的基本流信息.注意你必须使用--sout="#description"播放媒体恰好一次，否则将得到一个空的数组。而多次播放则会导致多个重复数据。 |
