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FFmpeg/libavdevice/avdevice.h
Diederick Niehorster a8a530331f avdevice: add info about media types(s) to AVDeviceInfo
An avdevice, regardless of whether its category says its an audio or
video device, may provide access to devices providing different media
types, or even single devices providing multiple media types. Also, some
devices may provide no media types. dshow is an example encompassing all
of these cases. Users should be provided with this information, so
AVDeviceInfo is extended to provide it.

Bump avdevice version

Signed-off-by: Diederick Niehorster <dcnieho@gmail.com>
Reviewed-by: Roger Pack <rogerdpack2@gmail.com>
2021-12-24 14:06:45 +05:30

522 lines
18 KiB
C

/*
* 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 libavdevice
* 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 xcbgrab 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.
*/
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.
*/
const AVInputFormat *av_input_audio_device_next(const 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.
*/
const AVInputFormat *av_input_video_device_next(const 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.
*/
const AVOutputFormat *av_output_audio_device_next(const 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.
*/
const AVOutputFormat *av_output_video_device_next(const 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);
#if FF_API_DEVICE_CAPABILITIES
/**
* 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.
*/
attribute_deprecated
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.
*/
attribute_deprecated
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.
*/
attribute_deprecated
void avdevice_capabilities_free(AVDeviceCapabilitiesQuery **caps, AVFormatContext *s);
#endif
/**
* 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 */
enum AVMediaType *media_types; /**< array indicating what media types(s), if any, a device can provide. If null, cannot provide any */
int nb_media_types; /**< length of media_types array, 0 if device cannot provide any media types */
} 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(const AVInputFormat *device, const char *device_name,
AVDictionary *device_options, AVDeviceInfoList **device_list);
int avdevice_list_output_sinks(const AVOutputFormat *device, const char *device_name,
AVDictionary *device_options, AVDeviceInfoList **device_list);
/**
* @}
*/
#endif /* AVDEVICE_AVDEVICE_H */