lib_camera.py

import numpy as np
import mvsdk
import platform

class Camera(object):
	"""
	Class for the industrial camera
	"""
	def __init__(self, DevInfo):
		"""
		Init
		"""
		super(Camera, self).__init__()
		self.DevInfo = DevInfo
		self.hCamera = 0
		self.cap = None
		self.pFrameBuffer = 0

	def open(self):
		"""
		Open the camera
		"""
		if self.hCamera > 0:
			return True

		# Open the camera
		hCamera = 0
		try:
			hCamera = mvsdk.CameraInit(self.DevInfo, -1, -1)
		except mvsdk.CameraException as e:
			print("CameraInit Failed({}): {}".format(e.error_code, e.message) )
			return False

		# Get the capability of the camera
		cap = mvsdk.CameraGetCapability(hCamera)

		# Get the type of the camera
		monoCamera = (cap.sIspCapacity.bMonoSensor != 0)

		if monoCamera:
			mvsdk.CameraSetIspOutFormat(hCamera, mvsdk.CAMERA_MEDIA_TYPE_MONO8)
		else:
			mvsdk.CameraSetIspOutFormat(hCamera, mvsdk.CAMERA_MEDIA_TYPE_BGR8)

		# Calculate the size of the RGB buffer according to the maximum resolution
		FrameBufferSize = cap.sResolutionRange.iWidthMax * cap.sResolutionRange.iHeightMax * (1 if monoCamera else 3)

		# Allocate the RGB buffer for storing the ISP image
		pFrameBuffer = mvsdk.CameraAlignMalloc(FrameBufferSize, 16)

		# Set the trigger mode for the camera: continurous mode
		mvsdk.CameraSetTriggerMode(hCamera, 0)

		# Set thr exposure time: 30ms
		mvsdk.CameraSetAeState(hCamera, 0)
		mvsdk.CameraSetExposureTime(hCamera, 30 * 1000)

		# Start to get the image
		mvsdk.CameraPlay(hCamera)

		self.hCamera = hCamera
		self.pFrameBuffer = pFrameBuffer
		self.cap = cap
		return True

	def close(self):
		"""
		Close the camera
		"""
		if self.hCamera > 0:
			mvsdk.CameraUnInit(self.hCamera)
			self.hCamera = 0

		mvsdk.CameraAlignFree(self.pFrameBuffer)
		self.pFrameBuffer = 0

	def grab(self):
		"""
		Grab an image from the camera
		"""
		hCamera = self.hCamera
		pFrameBuffer = self.pFrameBuffer
		try:
			pRawData, FrameHead = mvsdk.CameraGetImageBuffer(hCamera, 200)
			mvsdk.CameraImageProcess(hCamera, pRawData, pFrameBuffer, FrameHead)
			mvsdk.CameraReleaseImageBuffer(hCamera, pRawData)

			if platform.system() == "Windows":
				mvsdk.CameraFlipFrameBuffer(pFrameBuffer, FrameHead, 1)
			
			frame_data = (mvsdk.c_ubyte * FrameHead.uBytes).from_address(pFrameBuffer)
			frame = np.frombuffer(frame_data, dtype=np.uint8)
			frame = frame.reshape((FrameHead.iHeight, FrameHead.iWidth, 1 if FrameHead.uiMediaType == mvsdk.CAMERA_MEDIA_TYPE_MONO8 else 3) )
			return frame
			
		except mvsdk.CameraException as e:
			if e.error_code != mvsdk.CAMERA_STATUS_TIME_OUT:
				print("CameraGetImageBuffer failed({}): {}".format(e.error_code, e.message) )
			return None