DeepStream Metadata Extension

Detailed Description

Defines an API for managing GStreamer DeepStream metadata.

DeepStream Metadata is attached to a buffer with gst_buffer_add_nvds_meta(). Its metadata type is set to NVDS_BATCH_GST_META.

Multiple groups of metadata may be attached by different elements. gst_buffer_get_nvds_meta() gets the last added NvDsMeta.

The NvDsMeta::meta_data structure member must be cast to a meaningful structure pointer based on the meta_type. For example, for meta_type = NVDS_BATCH_GST_META, meta_data must be cast as (NvDsBatchMeta *).

Data Structures
struct	_NvDsMeta
	Holds DeepSteam metadata. More...

Macros
#define	NVDS_META_API_TYPE   (nvds_meta_api_get_type())
#define	NVDS_META_INFO   (nvds_meta_get_info())
#define	NVDS_META_STRING   "nvdsmeta"

Typedefs
typedef struct _NvDsMeta	NvDsMeta
	Holds DeepSteam metadata. More...

Enumerations
enum	GstNvDsMetaType {   NVDS_GST_INVALID_META =-1,   NVDS_BATCH_GST_META = NVDS_GST_CUSTOM_META + 1,   NVDS_DECODER_GST_META,   NVDS_DEWARPER_GST_META,   NVDS_BUFFER_GST_AS_FRAME_USER_META,   NVDS_RESERVED_GST_META = NVDS_GST_CUSTOM_META + 4096,   NVDS_GST_META_FORCE32 = 0x7FFFFFFF }
	Defines the type of metadata. More...

Functions
GType	nvds_meta_api_get_type (void)
const GstMetaInfo *	nvds_meta_get_info (void)
NvDsMeta *	gst_buffer_add_nvds_meta (GstBuffer *buffer, gpointer meta_data, gpointer user_data, NvDsMetaCopyFunc copy_func, NvDsMetaReleaseFunc release_func)
	Adds GstMeta of type NvDsMeta to the GstBuffer and sets the meta_data member of NvDsMeta. More...
NvDsMeta *	gst_buffer_get_nvds_meta (GstBuffer *buffer)
	Gets the NvDsMeta last added to a GstBuffer. More...
NvDsBatchMeta *	gst_buffer_get_nvds_batch_meta (GstBuffer *buffer)
	Gets the NvDsBatchMeta added to a GstBuffer. More...
void	nvds_copy_gst_meta_to_frame_meta (GstBuffer *src_gst_buffer, NvDsBatchMeta *batch_meta, NvDsFrameMeta *frame_meta)
	Copies all GstMeta objects on src_gst_buffer to the batched buffer's NvDsBatchMeta The GstMeta objects are copied into the user_meta_list within NvDsFrameMeta. More...
void	nvds_copy_gst_meta_to_audio_frame_meta (GstBuffer *src_gst_buffer, NvDsBatchMeta *batch_meta, NvDsAudioFrameMeta *frame_meta)
	Copies all GstMeta objects on src_gst_buffer to the batched buffer's NvDsBatchMeta The GstMeta objects are copied into the user_meta_list within NvDsAudioFrameMeta. More...

Macro Definition Documentation

NVDS_META_API_TYPE

#define NVDS_META_API_TYPE   (nvds_meta_api_get_type())

Definition at line 56 of file gstnvdsmeta.h.

NVDS_META_INFO

#define NVDS_META_INFO   (nvds_meta_get_info())

Definition at line 60 of file gstnvdsmeta.h.

NVDS_META_STRING

#define NVDS_META_STRING   "nvdsmeta"

Definition at line 62 of file gstnvdsmeta.h.

Typedef Documentation

NvDsMeta

typedef struct _NvDsMeta NvDsMeta

Holds DeepSteam metadata.

Enumeration Type Documentation

GstNvDsMetaType

enum GstNvDsMetaType

Defines the type of metadata.

NVIDIA-defined GstNvDsMetaType values are in the range from NVDS_BATCH_GST_META to NVDS_START_USER_META.

Enumerator
NVDS_GST_INVALID_META
NVDS_BATCH_GST_META
NVDS_DECODER_GST_META
NVDS_DEWARPER_GST_META
NVDS_BUFFER_GST_AS_FRAME_USER_META
NVDS_RESERVED_GST_META
NVDS_GST_META_FORCE32

Definition at line 68 of file gstnvdsmeta.h.

Function Documentation

gst_buffer_add_nvds_meta()

NvDsMeta* gst_buffer_add_nvds_meta	(	GstBuffer *	buffer,
		gpointer	meta_data,
		gpointer	user_data,
		NvDsMetaCopyFunc	copy_func,
		NvDsMetaReleaseFunc	release_func
	)

Adds GstMeta of type NvDsMeta to the GstBuffer and sets the meta_data member of NvDsMeta.

Parameters

[in]	buffer	A pointer to a GstBuffer to which the function adds metadata.
[in]	meta_data	A pointer at which the function sets the meta_data member of NvDsMeta.
[in]	user_data	A pointer to the user-specific data.
[in]	copy_func	The callback to be called when NvDsMeta is to be copied. The function is called with meta_data and user_data as parameters.
[in]	release_func	The callback to be called when NvDsMeta is to be destroyed. The function is called with meta_data and user_data as parameters.

Returns

A pointer to the attached NvDsMeta structure if successful, or NULL otherwise.

gst_buffer_get_nvds_batch_meta()

NvDsBatchMeta* gst_buffer_get_nvds_batch_meta

(

GstBuffer *

buffer

)

Gets the NvDsBatchMeta added to a GstBuffer.

Parameters

[in]

buffer

A pointer to the GstBuffer.

Returns

A pointer to the NvDsBatchMeta structure, or NULL if no NvDsMeta was attached.

gst_buffer_get_nvds_meta()

NvDsMeta* gst_buffer_get_nvds_meta

(

GstBuffer *

buffer

)

Gets the NvDsMeta last added to a GstBuffer.

Parameters

[in]

buffer

A pointer to the GstBuffer.

Returns

A pointer to the last added NvDsMeta structure, or NULL if no NvDsMeta was attached.

nvds_copy_gst_meta_to_audio_frame_meta()

void nvds_copy_gst_meta_to_audio_frame_meta	(	GstBuffer *	src_gst_buffer,
		NvDsBatchMeta *	batch_meta,
		NvDsAudioFrameMeta *	frame_meta
	)

Copies all GstMeta objects on src_gst_buffer to the batched buffer's NvDsBatchMeta The GstMeta objects are copied into the user_meta_list within NvDsAudioFrameMeta.

Note: the list of plain GstMeta from @src_gst_buffer are copied into @frame_meta as a single frame_meta->user_meta with NvDsUserMeta->base_meta.meta_type == NVDS_USER_FRAME_META_GST_META. The list of N X NvDsMeta from @src_gst_buffer are copied into @frame_meta as N X frame_meta->user_meta with each NvDsUserMeta->base_meta.meta_type == NvDsMeta->meta_type.

Parameters

[in]	src_gst_buffer	A pointer to the GstBuffer. GstMeta objects in this GstBuffer will be copied.
[in]	batch_meta	A pointer to the NvDsBatchMeta obtained from nvstreammux plugin. (Note: Works only for nvstreammux2 (Beta))
[in]	frame_meta	A pointer to the NvDsAudioFrameMeta NvDsAudioFrameMeta (metadata) for the batched input frame to which GstMeta objects will be copied as frame NvDsUserMeta.

nvds_copy_gst_meta_to_frame_meta()

void nvds_copy_gst_meta_to_frame_meta	(	GstBuffer *	src_gst_buffer,
		NvDsBatchMeta *	batch_meta,
		NvDsFrameMeta *	frame_meta
	)

Copies all GstMeta objects on src_gst_buffer to the batched buffer's NvDsBatchMeta The GstMeta objects are copied into the user_meta_list within NvDsFrameMeta.

Note: the list of plain GstMeta from @src_gst_buffer are copied into @frame_meta as a single frame_meta->user_meta with NvDsUserMeta->base_meta.meta_type == NVDS_USER_FRAME_META_GST_META. The list of N X NvDsMeta from @src_gst_buffer are copied into @frame_meta as N X frame_meta->user_meta with each NvDsUserMeta->base_meta.meta_type == NvDsMeta->meta_type.

Parameters

[in]	src_gst_buffer	A pointer to the GstBuffer. GstMeta objects in this GstBuffer will be copied.
[in]	batch_meta	A pointer to the NvDsBatchMeta obtained from nvstreammux plugin. (Note: Works only for nvstreammux2 (Beta))
[in]	frame_meta	A pointer to the NvDsFrameMeta NvDsFrameMeta (metadata) for the batched input frame to which GstMeta objects will be copied as frame NvDsUserMeta.

nvds_meta_api_get_type()

GType nvds_meta_api_get_type

(

void

)

nvds_meta_get_info()

const GstMetaInfo* nvds_meta_get_info

(

void

)