Latency Measurement API

Detailed Description

Defines an API for measuring latency in modules.

Data Structures
struct	_NvDsMetaCompLatency
	Holds information about latency of the given component. More...
struct	NvDsFrameLatencyInfo
	Holds information about latency of the given frame. More...

Macros
#define	MAX_COMPONENT_LEN   64
#define	nvds_enable_latency_measurement   (nvds_get_enable_latency_measurement())
	variable holding the return value of nvds_get_enable_latency_measurement() More...

Typedefs
typedef struct _NvDsMetaCompLatency	NvDsMetaCompLatency
	Holds information about latency of the given component. More...

Functions
NvDsUserMeta *	nvds_set_input_system_timestamp (GstBuffer *buffer, gchar *element_name)
	Sets the system timestamp when the gst buffer arrives at the input of the component. More...
gboolean	nvds_set_output_system_timestamp (GstBuffer *buffer, gchar *element_name)
	Sets the system timestamp when the gst buffer is pushed to the downstream component. More...
guint	nvds_measure_buffer_latency (GstBuffer *buf, NvDsFrameLatencyInfo *latency_info)
	Measures the latency of all the frames present in the current batch The latency will be computed till the point buf reaches. More...
gboolean	nvds_get_enable_latency_measurement (void)

Macro Definition Documentation

#define MAX_COMPONENT_LEN   64

Definition at line 33 of file nvds_latency_meta.h.

#define nvds_enable_latency_measurement   (nvds_get_enable_latency_measurement())

variable holding the return value of nvds_get_enable_latency_measurement()

Returns

a boolean set to TRUE if environment variable NVDS_ENABLE_LATENCY_MEASUREMENT is exported

Definition at line 149 of file nvds_latency_meta.h.

Typedef Documentation

typedef struct _NvDsMetaCompLatency NvDsMetaCompLatency

Holds information about latency of the given component.

Function Documentation

gboolean nvds_get_enable_latency_measurement

(

void

)

Returns

a boolean set to TRUE if environment variable NVDS_ENABLE_LATENCY_MEASUREMENT is exported

guint nvds_measure_buffer_latency	(	GstBuffer *	buf,
		NvDsFrameLatencyInfo *	latency_info
	)

Measures the latency of all the frames present in the current batch The latency will be computed till the point buf reaches.

User can install the probe on the either pads of the component and call this API to measure the latency.

Parameters

[in]	buf	GstBuffer which has NvDsBatchMeta attched as metadata
[out]	latency_info	A pointer to NvDsFrameLatencyInfo. It should be allocated as per batch-size. It will contain latency information of all the sources when the function returns.

NvDsUserMeta* nvds_set_input_system_timestamp	(	GstBuffer *	buffer,
		gchar *	element_name
	)

Sets the system timestamp when the gst buffer arrives at the input of the component.

Parameters

[in]	buffer	GstBuffer which arrives at the input of the component
[in]	element_name	pointer to the name of the component for which latency is to be measured

Returns

A pointer to NvDsUserMeta structure. It holds NvDsMetaCompLatency as user_meta_data

gboolean nvds_set_output_system_timestamp	(	GstBuffer *	buffer,
		gchar *	element_name
	)

Sets the system timestamp when the gst buffer is pushed to the downstream component.

It is a corresponding call to nvds_set_input_system_timestamp()

Parameters

[in]	buffer	GstBuffer which is pushed to the downstream component
[in]	element_name	A pointer to the name of the component for which latency is to be measured

returns TRUE if output timestamp is attached successfully, otherwise FALSE