Hi, So i am trying to get appropriate lighting for th RGB camera. I know i can't trigger the light using the camera as the Left Stero camera is the event to strobe the light and i will see the rolling shutter band effect on the RGB camera. However what i am trying to do is use an external trigger for both the strobe light and the camera and time the trigger signals for the light and the camera in such a way that i can get good light for my RGB image to capture fast moving objects. However, as i see [here](https://docs.luxonis.com/hardware/platform/deploy/frame-sync/) the FSYNC input triggers the left stereo camera that internally triggers the right mono camera. I also tried the [example script](https://gist.github.com/Erol444/0138af63378dc8de5b3f7d80db1ea1a5) and was only able to get Stero Camera images no RGB camera images. Is there a way I can get the RGB camera image based on the trigger or the left stereo camera event? This would help me time my strobe light as well accordingly. Thanks, Yishu

Triggering the Stereo Camera and accessing the RGB Image as well.

yishu_corpex

Hi,

So i am trying to get appropriate lighting for th RGB camera. I know i can't trigger the light using the camera as the Left Stero camera is the event to strobe the light and i will see the rolling shutter band effect on the RGB camera.

However what i am trying to do is use an external trigger for both the strobe light and the camera and time the trigger signals for the light and the camera in such a way that i can get good light for my RGB image to capture fast moving objects. However, as i see here the FSYNC input triggers the left stereo camera that internally triggers the right mono camera. I also tried the example script and was only able to get Stero Camera images no RGB camera images.

Is there a way I can get the RGB camera image based on the trigger or the left stereo camera event? This would help me time my strobe light as well accordingly.

Thanks,
Yishu

jakaskerl

Hi yishu_corpex
The FSYNC signal for the RGB has to be constant and set to the same FPS as the RGB camera. Then you set them all to expect outside signal with setExternalTrigger() and set them all to INPUT. Then you should have same triggering for all three cameras + the strobe.

Thanks,
Jaka

yishu_corpex

jakaskerl

So in the below code from the example all the three cameras are set to expect outside signal with setExternalTrigger() and are set all to INPUT. But this way I didn't get the RGB image.

So what you mean is I have to set the FPS of the RGB camera say to 10 FPS and the external trigger that the camera gets should also be at the same rate that is 10 FPS. This way we should be able to get all the three images and the strobe as well. This is what you meant right??

#!/usr/bin/env python3
import depthai as dai
import cv2
import time

pipeline = dai.Pipeline()

camRgb = pipeline.create(dai.node.ColorCamera)
camRgb.setColorOrder(dai.ColorCameraProperties.ColorOrder.RGB)
camRgb.setIspScale(2,3)
camRgb.initialControl.setFrameSyncMode(dai.CameraControl.FrameSyncMode.INPUT)
camRgb.initialControl.setExternalTrigger(4,3)

xoutRgb = pipeline.create(dai.node.XLinkOut)
xoutRgb.setStreamName("color")
camRgb.isp.link(xoutRgb.input)

monoLeft = pipeline.create(dai.node.MonoCamera)
monoLeft.setResolution(dai.MonoCameraProperties.SensorResolution.THE_720_P)
monoLeft.setBoardSocket(dai.CameraBoardSocket.LEFT)
monoLeft.initialControl.setFrameSyncMode(dai.CameraControl.FrameSyncMode.INPUT)
monoLeft.initialControl.setExternalTrigger(4,3)

xoutLeft = pipeline.create(dai.node.XLinkOut)
xoutLeft.setStreamName("left")
monoLeft.out.link(xoutLeft.input)

monoRight = pipeline.createMonoCamera()
monoRight.setResolution(dai.MonoCameraProperties.SensorResolution.THE_720_P)
monoRight.setBoardSocket(dai.CameraBoardSocket.RIGHT)
monoRight.initialControl.setFrameSyncMode(dai.CameraControl.FrameSyncMode.INPUT)
monoRight.initialControl.setExternalTrigger(4,3)

xoutRight = pipeline.create(dai.node.XLinkOut)
xoutRight.setStreamName("right")
monoRight.out.link(xoutRight.input)

# Connect to device with pipeline
with dai.Device(pipeline) as device:
    arr = ['left', 'right', 'color']
    queues = {}
    frames = {}

    for name in arr:
        queues[name] = device.getOutputQueue(name)

    print("Starting...")

    while True:
        #print("No frames")
        for name in arr:
            if queues[name].has():
                #print("Image Available")
                frames[name]=queues[name].get().getCvFrame()

        for name, frame in frames.items():
            cv2.imshow(name, frame)

        key = cv2.waitKey(1)
        if key == ord('q'):
            break

Thanks & Regards,
Yishu

jakaskerl

yishu_corpex
The code looks correct, I think. What you are probably missing is the camRgb.setFps(10).

Thanks,
Jaka