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/*
* This file is part of FFmpeg.
*
* FFmpeg 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.
*
* FFmpeg 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 FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef AVDEVICE_AVDEVICE_H
#define AVDEVICE_AVDEVICE_H
#include "version.h"
/**
* @file
* @ingroup lavd
* Main libavdevice API header
*/
/**
* @defgroup lavd Special devices muxing/demuxing library
* @{
* Libavdevice is a complementary library to @ref libavf "libavformat". It
* provides various "special" platform-specific muxers and demuxers, e.g. for
* grabbing devices, audio capture and playback etc. As a consequence, the
* (de)muxers in libavdevice are of the AVFMT_NOFILE type (they use their own
* I/O functions). The filename passed to avformat_open_input() often does not
* refer to an actually existing file, but has some special device-specific
* meaning - e.g. for x11grab it is the display name.
*
* To use libavdevice, simply call avdevice_register_all() to register all
* compiled muxers and demuxers. They all use standard libavformat API.
* @}
*/
#include "libavformat/avformat.h"
/**
* Return the LIBAVDEVICE_VERSION_INT constant.
*/
unsigned avdevice_version(void);
/**
* Return the libavdevice build-time configuration.
*/
const char *avdevice_configuration(void);
/**
* Return the libavdevice license.
*/
const char *avdevice_license(void);
/**
* Initialize libavdevice and register all the input and output devices.
* @warning This function is not thread safe.
*/
void avdevice_register_all(void);
typedef struct AVDeviceRect {
int x; /**< x coordinate of top left corner */
int y; /**< y coordinate of top left corner */
int width; /**< width */
int height; /**< height */
} AVDeviceRect;
/**
* Message types used by avdevice_app_to_dev_control_message().
*/
enum AVAppToDevMessageType {
/**
* Dummy message.
*/
AV_APP_TO_DEV_NONE = MKBETAG('N','O','N','E'),
/**
* Window size change message.
*
* Message is sent to the device every time the application changes the size
* of the window device renders to.
* Message should also be sent right after window is created.
*
* data: AVDeviceRect: new window size.
*/
AV_APP_TO_DEV_WINDOW_SIZE = MKBETAG('G','E','O','M'),
/**
* Repaint request message.
*
* Message is sent to the device when window have to be rapainted.
*
* data: AVDeviceRect: area required to be repainted.
* NULL: whole area is required to be repainted.
*/
AV_APP_TO_DEV_WINDOW_REPAINT = MKBETAG('R','E','P','A')
};
/**
* Message types used by avdevice_dev_to_app_control_message().
*/
enum AVDevToAppMessageType {
/**
* Dummy message.
*/
AV_DEV_TO_APP_NONE = MKBETAG('N','O','N','E'),
/**
* Create window buffer message.
*
* Device requests to create a window buffer. Exact meaning is device-
* and application-dependent. Message is sent before rendering first
* frame and all one-shot initializations should be done here.
* Application is allowed to ignore preferred window buffer size.
*
* @note: Application is obligated to inform about window buffer size
* with AV_APP_TO_DEV_WINDOW_SIZE message.
*
* data: AVDeviceRect: preferred size of the window buffer.
* NULL: no preferred size of the window buffer.
*/
AV_DEV_TO_APP_CREATE_WINDOW_BUFFER = MKBETAG('B','C','R','E'),
/**
* Prepare window buffer message.
*
* Device requests to prepare a window buffer for rendering.
* Exact meaning is device- and application-dependent.
* Message is sent before rendering of each frame.
*
* data: NULL.
*/
AV_DEV_TO_APP_PREPARE_WINDOW_BUFFER = MKBETAG('B','P','R','E'),
/**
* Display window buffer message.
*
* Device requests to display a window buffer.
* Message is sent when new frame is ready to be displyed.
* Usually buffers need to be swapped in handler of this message.
*
* data: NULL.
*/
AV_DEV_TO_APP_DISPLAY_WINDOW_BUFFER = MKBETAG('B','D','I','S'),
/**
* Destroy window buffer message.
*
* Device requests to destroy a window buffer.
* Message is sent when device is about to be destroyed and window
* buffer is not required anymore.
*
* data: NULL.
*/
AV_DEV_TO_APP_DESTROY_WINDOW_BUFFER = MKBETAG('B','D','E','S')
};
/**
* Send control message from application to device.
*
* @param s device context.
* @param type message type.
* @param data message data. Exact type depends on message type.
* @param data_size size of message data.
* @return >= 0 on success, negative on error.
* AVERROR(ENOSYS) when device doesn't implement handler of the message.
*/
int avdevice_app_to_dev_control_message(struct AVFormatContext *s,
enum AVAppToDevMessageType type,
void *data, size_t data_size);
/**
* Send control message from device to application.
*
* @param s device context.
* @param type message type.
* @param data message data. Can be NULL.
* @param data_size size of message data.
* @return >= 0 on success, negative on error.
* AVERROR(ENOSYS) when application doesn't implement handler of the message.
*/
int avdevice_dev_to_app_control_message(struct AVFormatContext *s,
enum AVDevToAppMessageType type,
void *data, size_t data_size);
/**
* Structure describes basic parameters of the device.
*/
typedef struct AVDeviceInfo {
char *device_name; /**< device name, format depends on device */
char *device_description; /**< human friendly name */
} AVDeviceInfo;
/**
* List of devices.
*/
typedef struct AVDeviceInfoList {
AVDeviceInfo **devices; /**< list of autodetected devices */
int nb_devices; /**< number of autodetected devices */
int default_device; /**< index of default device or -1 if no default */
} AVDeviceInfoList;
/**
* List devices.
*
* Returns available device names and their parameters.
*
* @note: Some devices may accept system-dependent device names that cannot be
* autodetected. The list returned by this function cannot be assumed to
* be always completed.
*
* @param s device context.
* @param[out] device_list list of autodetected devices.
* @return count of autodetected devices, negative on error.
*/
int avdevice_list_devices(struct AVFormatContext *s, AVDeviceInfoList **device_list);
/**
* Convinient function to free result of avdevice_list_devices().
*
* @param devices device list to be freed.
*/
void avdevice_free_list_devices(AVDeviceInfoList **device_list);
#endif /* AVDEVICE_AVDEVICE_H */
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