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26 #include "libavutil/ffversion.h"
29 #if FF_API_DEVICE_CAPABILITIES
43 return FFMPEG_CONFIGURATION;
48 #define LICENSE_PREFIX "libavdevice license: "
53 void *
data,
size_t data_size)
55 if (!
s->oformat || !
s->oformat->control_message)
57 return s->oformat->control_message(
s,
type,
data, data_size);
61 void *
data,
size_t data_size)
63 if (!
s->control_message_cb)
65 return s->control_message_cb(
s,
type,
data, data_size);
68 #if FF_API_DEVICE_CAPABILITIES
87 if ((
s->oformat && !
s->oformat->get_device_list) ||
88 (
s->iformat && !
s->iformat->get_device_list)) {
96 (*device_list)->default_device = -1;
98 ret =
s->oformat->get_device_list(
s, *device_list);
100 ret =
s->iformat->get_device_list(
s, *device_list);
155 for (
i = 0;
i <
list->nb_devices;
i++) {
156 dev =
list->devices[
i];
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later. That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another. Frame references ownership and permissions
#define LIBAVDEVICE_VERSION_INT
char * device_name
device name, format depends on device
Following API allows user to probe device capabilities (supported codecs, pixel formats,...
int avdevice_list_devices(AVFormatContext *s, AVDeviceInfoList **device_list)
List devices.
const AVOption av_device_capabilities[]
AVOption table used by devices to implement device capabilities API.
int avdevice_capabilities_create(AVDeviceCapabilitiesQuery **caps, AVFormatContext *s, AVDictionary **device_options)
Initialize capabilities probing API based on AVOption API.
AVAppToDevMessageType
Message types used by avdevice_app_to_dev_control_message().
int avdevice_dev_to_app_control_message(struct AVFormatContext *s, enum AVDevToAppMessageType type, void *data, size_t data_size)
Send control message from device to application.
#define LIBAVDEVICE_VERSION_MICRO
int avdevice_list_output_sinks(const AVOutputFormat *device, const char *device_name, AVDictionary *device_options, AVDeviceInfoList **device_list)
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf type
int avdevice_list_input_sources(const AVInputFormat *device, const char *device_name, AVDictionary *device_options, AVDeviceInfoList **device_list)
List devices.
#define av_assert0(cond)
assert() equivalent, that is always enabled.
const char * avdevice_license(void)
Return the libavdevice license.
enum AVMediaType * media_types
array indicating what media types(s), if any, a device can provide.
static int list_devices_for_context(AVFormatContext *s, AVDictionary *options, AVDeviceInfoList **device_list)
const char * avdevice_configuration(void)
Return the libavdevice build-time configuration.
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining list
void avdevice_capabilities_free(AVDeviceCapabilitiesQuery **caps, AVFormatContext *s)
Free resources created by avdevice_capabilities_create()
const OptionDef options[]
Structure describes basic parameters of the device.
void avdevice_free_list_devices(AVDeviceInfoList **device_list)
Convenient function to free result of avdevice_list_devices().
#define AV_OPT_SEARCH_CHILDREN
Search in possible children of the given object first.
const char av_device_ffversion[]
int av_opt_set_dict2(void *obj, AVDictionary **options, int search_flags)
Set all the options from a given dictionary on an object.
void av_dict_free(AVDictionary **pm)
Free all the memory allocated for an AVDictionary struct and all keys and values.
AVDevToAppMessageType
Message types used by avdevice_dev_to_app_control_message().
char * device_description
human friendly name
unsigned avdevice_version(void)
Return the LIBAVDEVICE_VERSION_INT constant.
#define i(width, name, range_min, range_max)
void * av_mallocz(size_t size)
Allocate a memory block with alignment suitable for all memory accesses (including vectors if availab...
av_warn_unused_result int ff_alloc_input_device_context(struct AVFormatContext **avctx, const AVInputFormat *iformat, const char *format)
void avformat_free_context(AVFormatContext *s)
Free an AVFormatContext and all its streams.
int avdevice_app_to_dev_control_message(struct AVFormatContext *s, enum AVAppToDevMessageType type, void *data, size_t data_size)
Send control message from application to device.
int av_dict_copy(AVDictionary **dst, const AVDictionary *src, int flags)
Copy entries from one AVDictionary struct into another.