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FelixWa's avatar
FelixWa
Copper Contributor
Feb 15, 2022

Unity3d & MRTK open Hololens 2 camera on button click and display the image in the Untiy scene after

As described in the title I have a scene wich contains a button. I attached a script with the code you see below to a ```PhotoManager``` GameObject. The button runs ```TakePhoto()``` from the script below when the button gets pressed.


I expected that when you click the button, the HoloLens will open the camera and you can take a picture. Once the picture has been taken, the user should see it in the scene.
However, nothing happens when you click the button...

When i run the scene in unity and press the button in the game window i'm getting this error: ```InvalidOperationException: Sequence contains no elements```. (I dont have a webcam connected to my computer)

The code is form the Unity documentation.

 

using UnityEngine;
using System.Collections;
using System.Linq;
using UnityEngine.Windows.WebCam;

public class PhotoCaptureExample : MonoBehaviour
{
    PhotoCapture photoCaptureObject = null;
    Texture2D targetTexture = null;

    // Use this for initialization
    public void TakePhoto()
    {
        Resolution cameraResolution = PhotoCapture.SupportedResolutions.OrderByDescending((res) => res.width * res.height).First();
        targetTexture = new Texture2D(cameraResolution.width, cameraResolution.height);

        // Create a PhotoCapture object
        PhotoCapture.CreateAsync(false, delegate (PhotoCapture captureObject) {
            photoCaptureObject = captureObject;
            CameraParameters cameraParameters = new CameraParameters();
            cameraParameters.hologramOpacity = 0.0f;
            cameraParameters.cameraResolutionWidth = cameraResolution.width;
            cameraParameters.cameraResolutionHeight = cameraResolution.height;
            cameraParameters.pixelFormat = CapturePixelFormat.BGRA32;

            // Activate the camera
            photoCaptureObject.StartPhotoModeAsync(cameraParameters, delegate (PhotoCapture.PhotoCaptureResult result) {
                // Take a picture
                photoCaptureObject.TakePhotoAsync(OnCapturedPhotoToMemory);
            });
        });
    }

    void OnCapturedPhotoToMemory(PhotoCapture.PhotoCaptureResult result, PhotoCaptureFrame photoCaptureFrame)
    {
        // Copy the raw image data into the target texture
        photoCaptureFrame.UploadImageDataToTexture(targetTexture);

        // Create a GameObject to which the texture can be applied
        GameObject quad = GameObject.CreatePrimitive(PrimitiveType.Quad);
        Renderer quadRenderer = quad.GetComponent<Renderer>() as Renderer;
        quadRenderer.material = new Material(Shader.Find("Custom/Unlit/UnlitTexture"));

        quad.transform.parent = this.transform;
        quad.transform.localPosition = new Vector3(0.0f, 0.0f, 3.0f);

        quadRenderer.material.SetTexture("_MainTex", targetTexture);

        // Deactivate the camera
        photoCaptureObject.StopPhotoModeAsync(OnStoppedPhotoMode);
    }

    void OnStoppedPhotoMode(PhotoCapture.PhotoCaptureResult result)
    {
        // Shutdown the photo capture resource
        photoCaptureObject.Dispose();
        photoCaptureObject = null;
    }
}

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