0,0 → 1,509 |
/* |
* 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 "libavutil/log.h" |
#include "libavutil/opt.h" |
#include "libavutil/dict.h" |
#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); |
|
/** |
* Audio input devices iterator. |
* |
* If d is NULL, returns the first registered input audio/video device, |
* if d is non-NULL, returns the next registered input audio/video device after d |
* or NULL if d is the last one. |
*/ |
AVInputFormat *av_input_audio_device_next(AVInputFormat *d); |
|
/** |
* Video input devices iterator. |
* |
* If d is NULL, returns the first registered input audio/video device, |
* if d is non-NULL, returns the next registered input audio/video device after d |
* or NULL if d is the last one. |
*/ |
AVInputFormat *av_input_video_device_next(AVInputFormat *d); |
|
/** |
* Audio output devices iterator. |
* |
* If d is NULL, returns the first registered output audio/video device, |
* if d is non-NULL, returns the next registered output audio/video device after d |
* or NULL if d is the last one. |
*/ |
AVOutputFormat *av_output_audio_device_next(AVOutputFormat *d); |
|
/** |
* Video output devices iterator. |
* |
* If d is NULL, returns the first registered output audio/video device, |
* if d is non-NULL, returns the next registered output audio/video device after d |
* or NULL if d is the last one. |
*/ |
AVOutputFormat *av_output_video_device_next(AVOutputFormat *d); |
|
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 has to be repainted. |
* |
* 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'), |
|
/** |
* Request pause/play. |
* |
* Application requests pause/unpause playback. |
* Mostly usable with devices that have internal buffer. |
* By default devices are not paused. |
* |
* data: NULL |
*/ |
AV_APP_TO_DEV_PAUSE = MKBETAG('P', 'A', 'U', ' '), |
AV_APP_TO_DEV_PLAY = MKBETAG('P', 'L', 'A', 'Y'), |
AV_APP_TO_DEV_TOGGLE_PAUSE = MKBETAG('P', 'A', 'U', 'T'), |
|
/** |
* Volume control message. |
* |
* Set volume level. It may be device-dependent if volume |
* is changed per stream or system wide. Per stream volume |
* change is expected when possible. |
* |
* data: double: new volume with range of 0.0 - 1.0. |
*/ |
AV_APP_TO_DEV_SET_VOLUME = MKBETAG('S', 'V', 'O', 'L'), |
|
/** |
* Mute control messages. |
* |
* Change mute state. It may be device-dependent if mute status |
* is changed per stream or system wide. Per stream mute status |
* change is expected when possible. |
* |
* data: NULL. |
*/ |
AV_APP_TO_DEV_MUTE = MKBETAG(' ', 'M', 'U', 'T'), |
AV_APP_TO_DEV_UNMUTE = MKBETAG('U', 'M', 'U', 'T'), |
AV_APP_TO_DEV_TOGGLE_MUTE = MKBETAG('T', 'M', 'U', 'T'), |
|
/** |
* Get volume/mute messages. |
* |
* Force the device to send AV_DEV_TO_APP_VOLUME_LEVEL_CHANGED or |
* AV_DEV_TO_APP_MUTE_STATE_CHANGED command respectively. |
* |
* data: NULL. |
*/ |
AV_APP_TO_DEV_GET_VOLUME = MKBETAG('G', 'V', 'O', 'L'), |
AV_APP_TO_DEV_GET_MUTE = MKBETAG('G', 'M', 'U', 'T'), |
}; |
|
/** |
* 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 displayed. |
* 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'), |
|
/** |
* Buffer fullness status messages. |
* |
* Device signals buffer overflow/underflow. |
* |
* data: NULL. |
*/ |
AV_DEV_TO_APP_BUFFER_OVERFLOW = MKBETAG('B','O','F','L'), |
AV_DEV_TO_APP_BUFFER_UNDERFLOW = MKBETAG('B','U','F','L'), |
|
/** |
* Buffer readable/writable. |
* |
* Device informs that buffer is readable/writable. |
* When possible, device informs how many bytes can be read/write. |
* |
* @warning Device may not inform when number of bytes than can be read/write changes. |
* |
* data: int64_t: amount of bytes available to read/write. |
* NULL: amount of bytes available to read/write is not known. |
*/ |
AV_DEV_TO_APP_BUFFER_READABLE = MKBETAG('B','R','D',' '), |
AV_DEV_TO_APP_BUFFER_WRITABLE = MKBETAG('B','W','R',' '), |
|
/** |
* Mute state change message. |
* |
* Device informs that mute state has changed. |
* |
* data: int: 0 for not muted state, non-zero for muted state. |
*/ |
AV_DEV_TO_APP_MUTE_STATE_CHANGED = MKBETAG('C','M','U','T'), |
|
/** |
* Volume level change message. |
* |
* Device informs that volume level has changed. |
* |
* data: double: new volume with range of 0.0 - 1.0. |
*/ |
AV_DEV_TO_APP_VOLUME_LEVEL_CHANGED = MKBETAG('C','V','O','L'), |
}; |
|
/** |
* 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); |
|
/** |
* Following API allows user to probe device capabilities (supported codecs, |
* pixel formats, sample formats, resolutions, channel counts, etc). |
* It is build on top op AVOption API. |
* Queried capabilities make it possible to set up converters of video or audio |
* parameters that fit to the device. |
* |
* List of capabilities that can be queried: |
* - Capabilities valid for both audio and video devices: |
* - codec: supported audio/video codecs. |
* type: AV_OPT_TYPE_INT (AVCodecID value) |
* - Capabilities valid for audio devices: |
* - sample_format: supported sample formats. |
* type: AV_OPT_TYPE_INT (AVSampleFormat value) |
* - sample_rate: supported sample rates. |
* type: AV_OPT_TYPE_INT |
* - channels: supported number of channels. |
* type: AV_OPT_TYPE_INT |
* - channel_layout: supported channel layouts. |
* type: AV_OPT_TYPE_INT64 |
* - Capabilities valid for video devices: |
* - pixel_format: supported pixel formats. |
* type: AV_OPT_TYPE_INT (AVPixelFormat value) |
* - window_size: supported window sizes (describes size of the window size presented to the user). |
* type: AV_OPT_TYPE_IMAGE_SIZE |
* - frame_size: supported frame sizes (describes size of provided video frames). |
* type: AV_OPT_TYPE_IMAGE_SIZE |
* - fps: supported fps values |
* type: AV_OPT_TYPE_RATIONAL |
* |
* Value of the capability may be set by user using av_opt_set() function |
* and AVDeviceCapabilitiesQuery object. Following queries will |
* limit results to the values matching already set capabilities. |
* For example, setting a codec may impact number of formats or fps values |
* returned during next query. Setting invalid value may limit results to zero. |
* |
* Example of the usage basing on opengl output device: |
* |
* @code |
* AVFormatContext *oc = NULL; |
* AVDeviceCapabilitiesQuery *caps = NULL; |
* AVOptionRanges *ranges; |
* int ret; |
* |
* if ((ret = avformat_alloc_output_context2(&oc, NULL, "opengl", NULL)) < 0) |
* goto fail; |
* if (avdevice_capabilities_create(&caps, oc, NULL) < 0) |
* goto fail; |
* |
* //query codecs |
* if (av_opt_query_ranges(&ranges, caps, "codec", AV_OPT_MULTI_COMPONENT_RANGE)) < 0) |
* goto fail; |
* //pick codec here and set it |
* av_opt_set(caps, "codec", AV_CODEC_ID_RAWVIDEO, 0); |
* |
* //query format |
* if (av_opt_query_ranges(&ranges, caps, "pixel_format", AV_OPT_MULTI_COMPONENT_RANGE)) < 0) |
* goto fail; |
* //pick format here and set it |
* av_opt_set(caps, "pixel_format", AV_PIX_FMT_YUV420P, 0); |
* |
* //query and set more capabilities |
* |
* fail: |
* //clean up code |
* avdevice_capabilities_free(&query, oc); |
* avformat_free_context(oc); |
* @endcode |
*/ |
|
/** |
* Structure describes device capabilities. |
* |
* It is used by devices in conjunction with av_device_capabilities AVOption table |
* to implement capabilities probing API based on AVOption API. Should not be used directly. |
*/ |
typedef struct AVDeviceCapabilitiesQuery { |
const AVClass *av_class; |
AVFormatContext *device_context; |
enum AVCodecID codec; |
enum AVSampleFormat sample_format; |
enum AVPixelFormat pixel_format; |
int sample_rate; |
int channels; |
int64_t channel_layout; |
int window_width; |
int window_height; |
int frame_width; |
int frame_height; |
AVRational fps; |
} AVDeviceCapabilitiesQuery; |
|
/** |
* AVOption table used by devices to implement device capabilities API. Should not be used by a user. |
*/ |
extern const AVOption av_device_capabilities[]; |
|
/** |
* Initialize capabilities probing API based on AVOption API. |
* |
* avdevice_capabilities_free() must be called when query capabilities API is |
* not used anymore. |
* |
* @param[out] caps Device capabilities data. Pointer to a NULL pointer must be passed. |
* @param s Context of the device. |
* @param device_options An AVDictionary filled with device-private options. |
* On return this parameter will be destroyed and replaced with a dict |
* containing options that were not found. May be NULL. |
* The same options must be passed later to avformat_write_header() for output |
* devices or avformat_open_input() for input devices, or at any other place |
* that affects device-private options. |
* |
* @return >= 0 on success, negative otherwise. |
*/ |
int avdevice_capabilities_create(AVDeviceCapabilitiesQuery **caps, AVFormatContext *s, |
AVDictionary **device_options); |
|
/** |
* Free resources created by avdevice_capabilities_create() |
* |
* @param caps Device capabilities data to be freed. |
* @param s Context of the device. |
*/ |
void avdevice_capabilities_free(AVDeviceCapabilitiesQuery **caps, AVFormatContext *s); |
|
/** |
* 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); |
|
/** |
* Convenient function to free result of avdevice_list_devices(). |
* |
* @param devices device list to be freed. |
*/ |
void avdevice_free_list_devices(AVDeviceInfoList **device_list); |
|
/** |
* List devices. |
* |
* Returns available device names and their parameters. |
* These are convinient wrappers for avdevice_list_devices(). |
* Device context is allocated and deallocated internally. |
* |
* @param device device format. May be NULL if device name is set. |
* @param device_name device name. May be NULL if device format is set. |
* @param device_options An AVDictionary filled with device-private options. May be NULL. |
* The same options must be passed later to avformat_write_header() for output |
* devices or avformat_open_input() for input devices, or at any other place |
* that affects device-private options. |
* @param[out] device_list list of autodetected devices |
* @return count of autodetected devices, negative on error. |
* @note device argument takes precedence over device_name when both are set. |
*/ |
int avdevice_list_input_sources(struct AVInputFormat *device, const char *device_name, |
AVDictionary *device_options, AVDeviceInfoList **device_list); |
int avdevice_list_output_sinks(struct AVOutputFormat *device, const char *device_name, |
AVDictionary *device_options, AVDeviceInfoList **device_list); |
|
#endif /* AVDEVICE_AVDEVICE_H */ |