1、下载OpenCV插件导入到新建的项目中，并在项目中新建一个RawImage，如下图：
2、将插件里的WebCamTextureToMatHelper脚本挂在RawImage上，并新建脚本命名为 FaceDetectTest2，将此脚本也挂在RawImage上，其他的什么都不用做。FaceDetectTest2脚本如下：
using OpenCVForUnity.CoreModule;
using OpenCVForUnity.ImgcodecsModule;
using OpenCVForUnity.ImgprocModule;
using OpenCVForUnity.ObjdetectModule;
using OpenCVForUnity.UnityUtils;
using OpenCVForUnity.UnityUtils.Helper;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;
public class FaceDetectTest2 : MonoBehaviour
{
public RawImage targetRaw;
public static string imageExtent = ".jpg";
private float counter = 0;
private float WAIT_TO_DETECT = 2f;
public string userLoginImagesPath;
private const int DETECT_IMG_COUNT = 5;
private int detectCounter;
public int DetectCounter { get => detectCounter; set => detectCounter = value; }
private int minNeighbors = 2; //最少检测到2次才算检测到
private int flags = 2; //性能参数
private float sizeScale = 0.2f; //阈值
/// <summary>
/// The texture.
/// </summary>
Texture2D texture;
/// <summary>
/// The gray mat.
/// </summary>
Mat grayMat;
/// <summary>
/// The faces.
/// </summary>
MatOfRect faces;
/// <summary>
/// The cascade.
/// </summary>
CascadeClassifier cascade;
/// <summary>
/// LBP_CASCADE_FILENAME
/// </summary>
protected static readonly string LBP_CASCADE_FILENAME = "lbpcascade_frontalface.xml";
WebCamTextureToMatHelper webCamTextureToMatHelper;
// Start is called before the first frame update
void Start()
{
userLoginImagesPath = Application.streamingAssetsPath + "/JieTu/";
//webCamTextureToMatHelper = gameObject.GetComponent<WebCamTextureToMatHelper>();
//webCamTextureToMatHelper.Initialize();
//Mat webCamTextureMat = webCamTextureToMatHelper.GetMat();
//texture = new Texture2D(webCamTextureMat.cols(), webCamTextureMat.rows(), TextureFormat.RGBA32, false);
Utils.fastMatToTexture2D(webCamTextureMat, texture);
//targetRaw.texture = texture;
OnWebCamTextureToMatHelperInitialized();
cascade = new CascadeClassifier();
cascade.load(Utils.getFilePath(LBP_CASCADE_FILENAME));
if (cascade.empty())
{
cascade.load(Utils.getFilePath("haarcascade_frontalface_alt.xml"));
Debug.Log("cascade file is not loaded. Please copy from “OpenCVForUnity/StreamingAssets/” to “Assets/StreamingAssets/” folder. ");
Debug.Log(cascade.empty());
}
}
public void OnWebCamTextureToMatHelperInitialized()
{
Debug.Log("OnWebCamTextureToMatHelperInitialized");
if (webCamTextureToMatHelper == null)
webCamTextureToMatHelper = gameObject.GetComponent<WebCamTextureToMatHelper>();
if (!webCamTextureToMatHelper.IsInitialized())
webCamTextureToMatHelper.Initialize(); //这个初始化就是获取摄像头画面
if (webCamTextureToMatHelper)
{
Mat webCamTextureMat = webCamTextureToMatHelper.GetMat(); //获取当前帧的画面
if (webCamTextureMat != null)
{
texture = new Texture2D(webCamTextureMat.cols(), webCamTextureMat.rows(), TextureFormat.RGBA32, false); //根据当前帧画面决定texture的摄像头贴图的大小
Utils.fastMatToTexture2D(webCamTextureMat, texture); //将Mat类型的贴图信息给texture
grayMat = new Mat(webCamTextureMat.rows(), webCamTextureMat.cols(), CvType.CV_8UC1);
faces = new MatOfRect();
}
}
if (targetRaw)
targetRaw.texture = texture; //texture赋值给RawImage就能显示出来了
Debug.Log("Screen.width " + Screen.width + " Screen.height " + Screen.height + " Screen.orientation " + Screen.orientation);
if (webCamTextureToMatHelper)
{
webCamTextureToMatHelper.Play();
}
}
// Update is called once per frame
void Update()
{
if (webCamTextureToMatHelper && webCamTextureToMatHelper.IsPlaying())
{
counter += Time.deltaTime;
Mat rgbaMat = webCamTextureToMatHelper.GetMat();//获取当前帧的画面
Imgproc.cvtColor(rgbaMat, grayMat, Imgproc.COLOR_RGBA2GRAY); //色彩转换 如果不加 图片颜色会不对
Imgproc.equalizeHist(grayMat, grayMat); //直方图均衡化（也是图像处理的一部分），均衡化之后使图片对比更明显
if (cascade != null)
cascade.detectMultiScale(grayMat, faces, 1.1d, minNeighbors, flags, new Size(grayMat.cols() * sizeScale, grayMat.rows() * sizeScale), new Size()); //检测镜头里多张脸 /* 1.1d为scaleFactor，必须大于1，值越大速度越快精度越低，反之值越小速度越慢精度越高。 minNeighbors：最少检测两次才算检测到。 flags:为性能参数。 new Size(grayMat.cols() * sizeScale：为检测目标的最小尺寸，低于这个尺寸的检测不到，或者不设置阈值。 grayMat.rows() * sizeScale：为检测目标的最大尺寸，高于这个尺寸的不检测，或者不设置阈值*/
OpenCVForUnity.CoreModule.Rect[] rects = faces.toArray();
if (rects.Length == 1 && counter > WAIT_TO_DETECT)
{
InterceptImg(rects[0], texture);
DetectCounter++;
if (DetectCounter == DETECT_IMG_COUNT)
{
OnPauseButtonClick();//停止
// onDetectImgsCallback?.Invoke(userLoginImagesPath + "3" + imageExtent);
}
}
//正常模式画线---镜头里框脸的绿色线
for (int i = 0; i < rects.Length; i++)
{
Debug.Log("detect faces " + rects[i]);
//绿色线
Imgproc.rectangle(rgbaMat, rects[i], new Scalar(14, 252, 123, 255), 3);
}
Utils.fastMatToTexture2D(rgbaMat, texture); //将处理过的贴图信息赋给texture
// onDetectFaceCallback?.Invoke(rects.Length > 0);
}
}
/// <summary>
/// 截取图片
/// </summary>
/// <param name="rect">要截取的区域</param>
void InterceptImg(OpenCVForUnity.CoreModule.Rect rect, Texture2D c_texture)
{
Mat cameraMat = new Mat(c_texture.height, c_texture.width, CvType.CV_8UC4);
Utils.texture2DToMat(c_texture, cameraMat);
//截取需要的部分 rect为上面检测的人脸区域
Mat croppedImage = new Mat(cameraMat, rect);
//色彩转换 如果不加 图片颜色会不对
Imgproc.cvtColor(croppedImage, croppedImage, Imgproc.COLOR_RGBA2BGRA);
//这里截取到的图片为倒的 使用这个方法翻转一下
Core.flip(croppedImage, croppedImage, 1);
//保存到Assets目录下
Imgcodecs.imwrite(userLoginImagesPath + DetectCounter + imageExtent, croppedImage);
}
/// <summary>
/// Raises the pause button click event.
/// </summary>
public void OnPauseButtonClick()
{
if (webCamTextureToMatHelper)
webCamTextureToMatHelper.Pause();
counter = 0;
}
}
3、代码解释：
webCamTextureToMatHelper.Initialize(); 初始化，这个方法就已经获取到了摄像头画面
Mat webCamTextureMat = webCamTextureToMatHelper.GetMat(); 获取当前帧的画面，获取到画面信息就可以进行各种骚操作了
OpenCV插件大体思路：
a、初始化调用摄像头
b、使用webCamTextureToMatHelper.GetMat()获取到当前帧动画
c、把 webCamTextureMat 赋给Texture2D类型的texture,然后再把texture给RawImage----这一步类似于做小地图一样将texture给RawImage，其实是Mat拿到相机每帧画面给texture，texture再给RawImage。在Update里做就可以每帧更新了，这样就有了相机画面了