trigger_input.py

"""
  Copyright (C) 2025 Allied Vision Technologies. All Rights Reserved.
  Subject to the BSD 3-Clause License.
"""

import sys
from vmbpy import *
from vmbpy.camera import CamerasTuple


def print_preamble() -> None:
    print('////////////////////////////////////////')
    print('/// Smart Camera Trigger Input Example ///')
    print('////////////////////////////////////////\n')


def print_usage() -> None:
    print('Usage:')
    print('    python trigger_input.py')
    print('    python trigger_input.py -h')
    print()


def abort(reason: str, return_code: int = 1, usage: bool = False) -> None:
    print(reason + '\n')

    if usage:
        print_usage()

    sys.exit(return_code)


def parse_args() -> None:
    args = sys.argv[1:]
    argc = len(args)

    for arg in args:
        if arg == '-h':
            print_usage()
            sys.exit(0)

    if argc > 0:
        abort(reason="Invalid number of arguments. Abort.", return_code=2, usage=True)


def frame_handler(camera: Camera, stream: Stream, frame: Frame) -> None:
    print('{} acquired {}'.format(camera, frame), flush=True)

    camera.queue_frame(frame)


if __name__ == '__main__':
    print_preamble()
    parse_args()

    with VmbSystem.get_instance() as vmb_system:
        cameras: CamerasTuple = vmb_system.get_all_cameras()
        if len(cameras) == 0:
            abort('No camera found.')
            
        with cameras[0] as camera:
            camera.LineSelector.set("Line0")
            try:
                camera.LineMode.set("Input")
            except:
                pass
    
            camera.TriggerSelector.set("FrameStart")
            camera.TriggerSource.set("Line0")
            camera.TriggerMode.set("On")
    
            print('\n Toggle the trigger input line between high and low to acquire a frame.')
            print('Press <enter> to stop frame acquisition.')
            camera.start_streaming(handler=frame_handler)
            input()
            camera.stop_streaming()