USB3 Vision Device

Includes APIs supported by USB3 vision devices. More...

Functions
def	MV_USB_SetTransferSize (self, nTransferSize)
	Sets transmission packet size of USB3 vision devices. More...
def	MV_USB_GetTransferSize (self, pnTransferSize)
	Gets transmission packet size of USB3 vision cameras. More...
def	MV_USB_SetTransferWays (self, nTransferWays)
	Sets the number of transmission channels of USB3 vision devices. More...
def	MV_USB_GetTransferWays (self, pnTransferWays)
	Gets the number of transmission channels of USB3 vision devices. More...
def	MV_USB_SetEventNodeNum (self, nEventNodeNum)
	Sets the number of event buffer nodes of USB3 vision devices. More...
def	MV_USB_SetSyncTimeOut (self, nMills)
	Sets the timeout duration for sync reading and writing of USB3 vision devices, range: [1000, UNIT_MAX]. More...
def	MV_USB_GetSyncTimeOut (self, nMills)
	Gets the timeout duration of sync reading and writing of USB3 vision devices. More...

Detailed Description

Includes APIs supported by USB3 vision devices.

Function Documentation

MV_USB_SetTransferSize()

def MvCameraControl_class.MV_USB_SetTransferSize	(		self,
			nTransferSize
	)

Sets transmission packet size of USB3 vision devices.

Parameters

handle	[IN] It refers to the device handle.
nTransferSize	[IN] It refers to the size of the transmission packet, unit: byte, default value: 1 MB (1,048,576 bytes). In Linux operating system, range: [0x8000, 0x200000].

Returns

Returns MV_OK for success, and returns corresponding Error Code for failure.

Remarks

Increasing the packet size can reduce the CPU usage, but for different computers and USB expansion cards, the compatibility is different. If the packet size is too large, image acquisition might fail.

MV_USB_GetTransferSize()

def MvCameraControl_class.MV_USB_GetTransferSize	(		self,
			pnTransferSize
	)

Gets transmission packet size of USB3 vision cameras.

Parameters

handle	[IN] It refers to the device handle.
pnTransferSize	[IN][OUT] It refers to the pointer to the size of the transmission packet, unit: byte.

Returns

Returns MV_OK for success, and returns corresponding Error Code for failure.

Remarks

Call this API to get the packet size of the current USB3 vision device (1 MB by default).

MV_USB_SetTransferWays()

def MvCameraControl_class.MV_USB_SetTransferWays	(		self,
			nTransferWays
	)

Sets the number of transmission channels of USB3 vision devices.

Parameters

handle	[IN] It refers to the device handle.
nTransferWays	[IN] It refers to the number of transmission channels, range: [1, 10].

Returns

Returns MV_OK for success, and returns corresponding Error Code for failure.

Remarks

This parameter can be adjusted based on computer performance, device image frame rate, device image size, and device memory usage. But compatibility differs due to different PC and USB expansion cards.

MV_USB_GetTransferWays()

def MvCameraControl_class.MV_USB_GetTransferWays	(		self,
			pnTransferWays
	)

Gets the number of transmission channels of USB3 vision devices.

Parameters

handle	[IN] It refers to the device handle.
pnTransferWays	[IN][OUT] It refers to the pointer to the number of transmission channels.

Returns

Returns MV_OK for success, and returns corresponding Error Code for failure.

Remarks

Call this API to get the current number of USB3 vision asynchronous image grabbing nodes. For USB3 vision cameras, the number of transmission channels is closely related to the payload packet size corresponding to the pixel format, and it can be calculated based on the max. asynchronous registration length / payload packet size of pixel format.

MV_USB_SetEventNodeNum()

def MvCameraControl_class.MV_USB_SetEventNodeNum	(		self,
			nEventNodeNum
	)

Sets the number of event buffer nodes of USB3 vision devices.

Parameters

handle	[IN] It refers to the device handle.
nEventNodeNum	[IN] It refers to the number of event buffer nodes, range: [1, 64].

Returns

Returns MV_OK for success, and returns corresponding Error Code for failure.

Remarks

Call this API to set the number of the buffer nodes for the current USB3 vision event. The default value is 5.

MV_USB_SetSyncTimeOut()

def MvCameraControl_class.MV_USB_SetSyncTimeOut	(		self,
			nMills
	)

Sets the timeout duration for sync reading and writing of USB3 vision devices, range: [1000, UNIT_MAX].

Parameters

handle	[IN] It refers to the device handle.
nMills	[IN] It refers to the timeout duration for sync reading and writing, unit: millisecond. It is 1000 ms by default.

Returns

Returns MV_OK for success, and returns corresponding Error Code for failure.

Remarks

Increasing the timeout duration for sync reading and writing can help deal with the problem that some cameras' parameter configuration process is very slow (more than 1000 ms).

MV_USB_GetSyncTimeOut()

def MvCameraControl_class.MV_USB_GetSyncTimeOut	(		self,
			nMills
	)

Gets the timeout duration of sync reading and writing of USB3 vision devices.

Parameters

handle	[IN] It refers to the device handle.
pnMills	[IN][OUT] It refers to the timeout duration, unit: millisecond.

Returns

Returns MV_OK for success, and returns corresponding Error Code for failure.

Remarks

Call this API to get the timeout duration of sync reading and writing of USB3 vision devices (1000 ms by default).