I want a video to be captured and saved for a certain duration of time, how to do that?

[sadiac]

I am using the following code to capture video from 2 cameras for a certain duration and then saving that video. But I get random timings. For example if I set the time to be 60 seconds, i sometimes get a 1 minute 14 seconds video on the jetson orin board, on another windows laptop i get the video for example as 40 seconds video. So its very random. How do i set the time so that I always get a fixed length video in the jetson when using this script. Thank you

#!/usr/bin/env python3
  
  import cv2
  import depthai as dai
  import contextlib
  
  from calc import HostSpatialsCalc
  from utility import *
  import numpy as np
  import math
  import time
  
  def createPipeline():
      # Start defining a pipeline
      pipeline = dai.Pipeline()
      # Define a source - color camera
      camRgb = pipeline.create(dai.node.ColorCamera)

    camRgb.setPreviewSize(300, 300)
    camRgb.setBoardSocket(dai.CameraBoardSocket.CAM_A)
    camRgb.setResolution(dai.ColorCameraProperties.SensorResolution.THE_1080_P)
    camRgb.setInterleaved(False)
    camRgb.setVideoSize(1920, 1080)

    # Create output
    xoutRgb = pipeline.create(dai.node.XLinkOut)
    xoutRgb.setStreamName("rgb")
    xoutRgb.input.setBlocking(False)
    xoutRgb.input.setQueueSize(1)
    

    # Define sources and outputs
    monoLeft = pipeline.create(dai.node.MonoCamera)
    monoRight = pipeline.create(dai.node.MonoCamera)


    # Properties
    monoLeft.setResolution(dai.MonoCameraProperties.SensorResolution.THE_400_P)
    monoLeft.setBoardSocket(dai.CameraBoardSocket.LEFT)
    monoRight.setResolution(dai.MonoCameraProperties.SensorResolution.THE_400_P)
    monoRight.setBoardSocket(dai.CameraBoardSocket.RIGHT)

    camRgb.video.link(xoutRgb.input)


    return pipeline


with contextlib.ExitStack() as stack:
    deviceInfos = dai.Device.getAllAvailableDevices()
    usbSpeed = dai.UsbSpeed.SUPER
    openVinoVersion = dai.OpenVINO.Version.VERSION_2021_4

    qRgbMap = []
    devices = []


    for deviceInfo in deviceInfos:
        deviceInfo: dai.DeviceInfo
        device: dai.Device = stack.enter_context(dai.Device(openVinoVersion, deviceInfo, usbSpeed))
        devices.append(device)
    
        mxId = device.getMxId()
        cameras = device.getConnectedCameras()
        usbSpeed = device.getUsbSpeed()
        eepromData = device.readCalibration2().getEepromData()
       

        pipeline, stereo= createPipeline()
        device.startPipeline(pipeline)

        # Output queue will be used to get the rgb frames from the output defined above
        timestr = time.strftime("%Y%m%d-%H%M%S")
        q_rgb = device.getOutputQueue(name="rgb", maxSize=4, blocking=False)
        stream_name = "rgb-" + mxId + "-" + eepromData.productName
        
        recording = (cv2.VideoWriter(f'filename_{mxId}_{timestr}.avi', cv2.VideoWriter_fourcc(*'MJPG'), 20, (1920, 1080)))
       
        qRgbMap.append((q_rgb, stream_name, recording))

      

    start_time = time.time()
 
    while(time.time() - start_time < 60):
        
        for q_rgb, stream_name , recording in qRgbMap:
          
            if q_rgb.has():
                video_in = q_rgb.get()
                recording.write(video_in.getCvFrame())

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

[ShaneCCC]

Maybe try count the frame for example if camera frame rate is 30 then get 1800 frame for 60s.

Thanks