for loop crashes unity

I intend to catch the camera, turn it to HSV and use this to do threshold for hand gesture tracking. But my for loop seems to crash Unity. I want to use a for loop since this shows the actions behind an image processing method, instead of using a library to do it for me. In the end i want to do convex hull detection and convex hull defects detection to return a number between 0 to 5 depending on the number of fingers showing, this 0 to 5 will then tell our game to use a spell or not depending on the number. This was just a bit of context tho, just need to get this for loop to work for now.

using Emgu.CV; using Emgu.CV.CvEnum; using Emgu.CV.Structure; using Emgu.CV.Features2D; using Emgu.CV.Util; using System.Collections; using System.Collections.Generic; using System.IO; using UnityEngine; using UnityEngine.UI; using Emgu.CV.Aruco;

public class GestureTrackingScript : MonoBehaviour {

 public VideoCapture cap;
 public RawImage camImage;
 int iteration = 0;

 // Use this for initialization
 void Start()
 {
     Debug.Log("Startup initiated...");
     cap = new VideoCapture(0); // instantiate a webcamera
     cap.SetCaptureProperty(CapProp.Fps, 30); // The FPS of the camera
     
     Debug.Log("Startup finished. Running...");
 }

 // Update is called once per frame
 void Update()
 {
     Image<Hsv, byte> frame = cap.QueryFrame().ToImage<Hsv, byte>(); // the input image (frame from camera)
    
     for (int j = 0; j < frame.Height; j++){
         for (int i = 0; i < frame.Width; i++){
             //lower
             frame = frame.ThresholdToZero(new Hsv(10.0, 22.0, 10.0));
             //upper
             frame = frame.ThresholdToZeroInv(new Hsv(100.0, 29.0, 100.0));
         }
     }

     MemoryStream _memory = new MemoryStream();
     frame.Bitmap.Save(_memory, frame.Bitmap.RawFormat);
     Texture2D camera = new Texture2D(400, 400);
     camera.LoadImage(_memory.ToArray());
     camImage.texture = camera;
     camImage.material.mainTexture = camera;
     Debug.Log("Ping Number " + iteration);
     iteration++;

 }

}