InterfaceAndDevice.py

Control Camera(s) Connected to Frame Grabber(s)

It shows how to enumerate one or more cameras connected to the self-developed frame grabber via enumeration APIs, and perform operations such as turning on cameras and grabbing images.

# -- coding: utf-8 --

import sys
import platform
import os
from ctypes import *

# Compatible with different operating systems to load DDL
currentsystem = platform.system()
if currentsystem == 'Windows':
    sys.path.append(os.path.join(os.getenv('MVCAM_COMMON_RUNENV'), "Samples", "Python", "MvImport"))
else:
    sys.path.append(os.path.join("..", "..", "MvImport"))

from MvCameraControl_class import *


# Compatible with input processing of Python 2.X and 3.X
if sys.version_info[0] < 3:
    # Python 2.x
    input_func = raw_input
else: 
    # Python 3.x
    input_func = input

# Decoding Characters
def decoding_char(ctypes_char_array):
    """
    Safely decode a string from a ctypes character array.
    Compatible with Python 2.x and 3.x, as well as 32-bit and 64-bit environments.
    """
    byte_str = memoryview(ctypes_char_array).tobytes()
    
    # Truncate at the first null character
    null_index = byte_str.find(b'\x00')
    if null_index != -1:
        byte_str = byte_str[:null_index]
    
    # Attempt to decode using multiple encodings
    for encoding in ['gbk', 'utf-8', 'latin-1']:
        try:
            return byte_str.decode(encoding)
        except UnicodeDecodeError:
            continue
    
    # If all encodings fail, use a replacement strategy
    return byte_str.decode('latin-1', errors='replace')
    
fun_ctype = get_platform_functype()

stFrameInfo = POINTER(MV_FRAME_OUT_INFO_EX)
pData = POINTER(c_ubyte)
FrameInfoCallBack = fun_ctype(None, pData, stFrameInfo, c_void_p)


def image_callback(pData, pFrameInfo, pUser):
        stFrameInfo = cast(pFrameInfo, POINTER(MV_FRAME_OUT_INFO_EX)).contents
        if stFrameInfo:
            print("get one frame: Width[%d], Height[%d], nFrameNum[%d]" % (stFrameInfo.nWidth, stFrameInfo.nHeight, stFrameInfo.nFrameNum))

CALL_BACK_FUN = FrameInfoCallBack(image_callback)


def print_devices_info(deviceList):
    for i in range(0, deviceList.nDeviceNum):
        mvcc_dev_info = cast(deviceList.pDeviceInfo[i], POINTER(MV_CC_DEVICE_INFO)).contents
        if mvcc_dev_info.nTLayerType == MV_GIGE_DEVICE or mvcc_dev_info.nTLayerType == MV_GENTL_GIGE_DEVICE:
            print ("\ngige device: [%d]" % i)
            strModeName = decoding_char(mvcc_dev_info.SpecialInfo.stGigEInfo.chModelName)
            print ("device model name: %s" % strModeName)

            nip1 = ((mvcc_dev_info.SpecialInfo.stGigEInfo.nCurrentIp & 0xff000000) >> 24)
            nip2 = ((mvcc_dev_info.SpecialInfo.stGigEInfo.nCurrentIp & 0x00ff0000) >> 16)
            nip3 = ((mvcc_dev_info.SpecialInfo.stGigEInfo.nCurrentIp & 0x0000ff00) >> 8)
            nip4 = (mvcc_dev_info.SpecialInfo.stGigEInfo.nCurrentIp & 0x000000ff)
            print ("current ip: %d.%d.%d.%d\n" % (nip1, nip2, nip3, nip4))
        elif mvcc_dev_info.nTLayerType == MV_USB_DEVICE:
            print ("\nu3v device: [%d]" % i)
            strModeName = decoding_char(mvcc_dev_info.SpecialInfo.stUsb3VInfo.chModelName)
            print ("device model name: %s" % strModeName)

            strSerialNumber = decoding_char(mvcc_dev_info.SpecialInfo.stUsb3VInfo.chSerialNumber)                
            print ("user serial number: %s" % strSerialNumber)
        elif mvcc_dev_info.nTLayerType == MV_GENTL_CAMERALINK_DEVICE:
            print ("\nCML device: [%d]" % i)
            strModeName = decoding_char(mvcc_dev_info.SpecialInfo.stCMLInfo.chModelName)
            print ("device model name: %s" % strModeName)

            strSerialNumber = decoding_char(mvcc_dev_info.SpecialInfo.stCMLInfo.chSerialNumber)
            print ("user serial number: %s" % strSerialNumber)
        elif mvcc_dev_info.nTLayerType == MV_GENTL_CXP_DEVICE:
            print ("\nCXP device: [%d]" % i)
            strModeName = decoding_char(mvcc_dev_info.SpecialInfo.stCXPInfo.chModelName)
            print ("device model name: %s" % strModeName)
            
            strSerialNumber = decoding_char(mvcc_dev_info.SpecialInfo.stCXPInfo.chSerialNumber)
            print ("user serial number: %s" % strSerialNumber)
        elif mvcc_dev_info.nTLayerType == MV_GENTL_XOF_DEVICE:
            print ("\nXoF device: [%d]" % i)
            strModeName = decoding_char(mvcc_dev_info.SpecialInfo.stXoFInfo.chModelName)
            print ("device model name: %s" % strModeName)

            strSerialNumber = decoding_char(mvcc_dev_info.SpecialInfo.stXoFInfo.chSerialNumber)
            print ("user serial number: %s" % strSerialNumber)


def print_interface_info(interfaceList):
    for i in range(0, interfaceList.nInterfaceNum):
        interfaceInfo = cast(interfaceList.pInterfaceInfos[i], POINTER(MV_INTERFACE_INFO)).contents
        print("interface: [%d]" % i)
        
        displayName = decoding_char(interfaceInfo.chDisplayName)
        print("display name: %s" % displayName)

        serialNumber = decoding_char(interfaceInfo.chSerialNumber)
        print("serial number: %s" % serialNumber)

        modelName = decoding_char(interfaceInfo.chModelName)
        print("model name: %s" % modelName)

        interfaceId = decoding_char(interfaceInfo.chInterfaceID)
        print("interface id: %s" % interfaceId)


if __name__ == "__main__":

    try:
        # Initialize SDK resources
        MvCamera.MV_CC_Initialize()

        SDKVersion = MvCamera.MV_CC_GetSDKVersion()
        print ("SDKVersion[0x%x]" % SDKVersion)
        
        interfaceList = MV_INTERFACE_INFO_LIST()
        transportLayerType = MV_GIGE_INTERFACE | MV_CAMERALINK_INTERFACE | MV_CXP_INTERFACE | MV_XOF_INTERFACE

        # Enumerate frame grabbers
        ret = MvCamera.MV_CC_EnumInterfaces(transportLayerType, interfaceList)
        if ret != 0:
            print("enum interfaces fail! ret[0x%x]" % ret)
            sys.exit()

        if interfaceList.nInterfaceNum == 0:
            print("find no interface!")
            sys.exit()

        print("Find %d interfaces!" % interfaceList.nInterfaceNum)
        print_interface_info(interfaceList)

        nInterfaceIndex = input_func("please input the number of the interface to connect:")

        if int(nInterfaceIndex) >= interfaceList.nInterfaceNum:
            print("input error!")
            sys.exit()

        # Create a camera instance
        cam_instance = MvCamera()
        interface_instance = MvCamera()

        # Select the frame grabber, and create a handle
        curInterface = cast(interfaceList.pInterfaceInfos[int(nInterfaceIndex)], POINTER(MV_INTERFACE_INFO)).contents

        ret = interface_instance.MV_CC_CreateInterface(curInterface)
        if ret != 0:
            raise Exception("create interface handle fail! ret[0x%x]" % ret)

        # Turn on the device
        ret = interface_instance.MV_CC_OpenInterface()
        if ret != 0:
            raise Exception("open interface fail! ret[0x%x]" % ret)
        else:
            print("open interface success")

        # Enumerates cameras connected to the frame grabber
        deviceList = MV_CC_DEVICE_INFO_LIST()
        ret = interface_instance.MV_CC_EnumDevicesByInterface(deviceList)
        if ret != 0:
            raise Exception("enum devices fail! ret[0x%x]" % ret)

        if deviceList.nDeviceNum == 0:
            raise Exception("find no device!")

        print_devices_info(deviceList)

        nCamIndex = input_func("please input the number of the device to connect:")

        if int(nCamIndex) >= deviceList.nDeviceNum:
            raise Exception("input error!")

        # Select a device, and create a handle
        stDeviceList = cast(deviceList.pDeviceInfo[int(nCamIndex)], POINTER(MV_CC_DEVICE_INFO)).contents

        ret = cam_instance.MV_CC_CreateHandle(stDeviceList)
        if ret != 0:
            raise Exception("create handle fail! ret[0x%x]" % ret)

        # Turn on the device
        ret = cam_instance.MV_CC_OpenDevice(MV_ACCESS_Exclusive, 0)
        if ret != 0:
            raise Exception("open device fail! ret[0x%x]" % ret)

        # Get optimal packet size (only supported by GigE devices)
        if stDeviceList.nTLayerType == MV_GIGE_DEVICE or stDeviceList.nTLayerType == MV_GENTL_GIGE_DEVICE:
            nPacketSize = cam_instance.MV_CC_GetOptimalPacketSize()
            if int(nPacketSize) > 0:
                ret = cam_instance.MV_CC_SetIntValue("GevSCPSPacketSize", nPacketSize)
                if ret != 0:
                    print("Warning: Set Packet Size fail! ret[0x%x]" % ret)
            else:
                print("Warning: Get Packet Size fail! ret[0x%x]" % nPacketSize)

        # Set trigger mode to off
        ret = cam_instance.MV_CC_SetEnumValue("TriggerMode", MV_TRIGGER_MODE_OFF)
        if ret != 0:
            raise Exception("set trigger mode fail! ret[0x%x]" % ret)

        #Register an image grabbing callback
        ret = cam_instance.MV_CC_RegisterImageCallBackEx(CALL_BACK_FUN, None)
        if ret != 0:
            raise Exception("register image callback fail! ret[0x%x]" % ret)

        # Start grabbing images
        ret = cam_instance.MV_CC_StartGrabbing()
        if ret != 0:
            raise Exception("start grabbing fail! ret[0x%x]" % ret)

        print ("press Enter key to stop grabbing.")
        input_func()

        # Stop grabbing images
        ret = cam_instance.MV_CC_StopGrabbing()
        if ret != 0:
            raise Exception("stop grabbing fail! ret[0x%x]" % ret)

        # Turn off the device
        ret = cam_instance.MV_CC_CloseDevice()
        if ret != 0:
            raise Exception("close deivce fail! ret[0x%x]" % ret)

        # Destroy the handle
        cam_instance.MV_CC_DestroyHandle()

        # Turn off the frame grabber
        interface_instance.MV_CC_CloseInterface()

        # Destroy frame grabber handle
        interface_instance.MV_CC_DestroyInterface()
    except Exception as e:
        print(e)
        cam_instance.MV_CC_CloseDevice()
        cam_instance.MV_CC_DestroyHandle()
        interface_instance.MV_CC_CloseInterface()
        interface_instance.MV_CC_DestroyInterface()

    finally:
        # Release SDK resources
        MvCamera.MV_CC_Finalize()