一次捕获后图像捕获失败
本文关键字：图像 失败 一次 | 更新日期: 2023-09-27 18:06:32
我正在做一个机器人曲棍球运动员的项目;
在项目中，我使用Microsoft lifecam来识别"球"的位置。这是工作。
问题是当我运行项目的主要形式-如果在进入游戏之前我检查相机(一张照片)这是按钮内部的代码:
Capture capture = new Capture(0);
Image<Emgu.CV.Structure.Bgr,byte> temp = capture.QueryFrame();
picture pic = new picture(temp);
pic.ShowDialog();
和检查后，我开始播放游戏停止给我这个错误:
An unhandled exception of type 'System.AccessViolationException'
occurred in Emgu.CV.dll
Additional information: Attempted to read or write protected memory.
This is often an indication that other memory is corrupt.
图像处理代码为:
class C_Camera
{
public Capture capWebCam = null;
public bool binCapturingInProgress = false;
public Image<Bgr, byte> imgOriginal;
public Image<Gray, byte> imgProcessed;
public ImageBox imageBox1 = new ImageBox();
public TextBox textBox1;
public List<PointF> centerList;
CircleF[] circles;
public void newCapture(bool b, List<PointF> centers)
{
centerList = centers;
binCapturingInProgress = b;
try
{
capWebCam = new Capture();
}
catch (NullReferenceException except)
{
MessageBox.Show(except.Message);
return;
}
Application.Idle += processFrameAndUpdateGUI;//add process image function to the applicationlist in tasks
binCapturingInProgress = true;
}
public void processFrameAndUpdateGUI(object sender, EventArgs arg)
{
imgOriginal = capWebCam.QueryFrame();
if (imgOriginal == null)
{
return;
}
imgProcessed = imgOriginal.InRange(new Bgr(0, 0, 150)/*min filter*/, new Bgr(80, 80, 256));
// imgProcessed = imgOriginal.InRange(new Bgr(0, 0, 175)/*min filter*/, new Bgr(100, 100, 256));
imgProcessed = imgProcessed.SmoothGaussian(9);//9
circles = imgProcessed.HoughCircles(new Gray(100), //canny threshhold
new Gray(50), //accumolator threshold
2,//size of image
imgProcessed.Height / 4, //min size in pixels between centers of detected circles
15, //min radios
43)[0];//max radios and get circles from first channel
foreach (CircleF circle in circles)
{
centerList.Add(circle.Center);
// circlesOfBalls.Add(circle);
if (textBox1.Text != "") textBox1.AppendText(Environment.NewLine);
textBox1.AppendText("ball position = x" + centerList[centerList.Count - 1].X +
", y = " + centerList[centerList.Count - 1].Y.ToString().PadLeft(4)
+ "centerList.Count= " + centerList.Count);
// + ", radios = " + centerList[centerList.Count - 1].Radius.ToString("###,000").PadLeft(7))
textBox1.ScrollToCaret();// scrolls the textBox to last line
// draw a small green circle in the center
CvInvoke.cvCircle(imgOriginal, // draw on the original image
new Point((int)circle.Center.X, (int)circle.Center.Y),//center point of circle
3, // radios of circle,
new MCvScalar (0, 255, 0), // draw in green color
-1, //indicates to fill the circle
LINE_TYPE.CV_AA, //smoothes the pixels
0);// no shift
//draw a red circle around the detected object
// if (imgOriginal.Data != null)
imgOriginal.Draw(circle, //current circle
new Bgr(Color.Red), // draw pure red
3);
} // end of for each
// if(imgOriginal.Data != null)
imageBox1.Image = imgOriginal;
}
我试着在谷歌和这里搜索答案，但找不到任何。如果我没有进入相机检查它是否工作正常
从表面上看，如果您只在系统空闲时捕获图像，那么您应该在系统空闲时捕获图像，但这可能太频繁或不够频繁。
尝试添加DispatcherTimer并赋予它渲染优先级和频率1000/60(60帧每秒)。
DispatcherTimer UpdateTimer;
public Capture capWebCam = null;
public bool binCapturingInProgress = false;
public Image<Bgr, byte> imgOriginal;
public Image<Gray, byte> imgProcessed;
public ImageBox imageBox1 = new ImageBox();
public TextBox textBox1;
public List<PointF> centerList;
CircleF[] circles;
public void newCapture(bool b, List<PointF> centers)
{
centerList = centers;
binCapturingInProgress = b;
try
{
capWebCam = new Capture();
}
catch (NullReferenceException except)
{
MessageBox.Show(except.Message);
return;
}
binCapturingInProgress = true;
//Start the timer after the device is ready to be captured (this looks like a good place to do it)
UpdateTimer = new DispatcherTimer(DispatcherPriority.Render);
UpdateTimer.Interval = TimeSpan.FromMilliseconds(1000 / 60);
UpdateTimer.Tick += processFrameAndUpdateGUI;
UpdateTimer.Start();
}
private void processFrameAndUpdateGUI(object o, EventArgs e)
{
//Capture new image, render it and display it.
imgOriginal = capWebCam.QueryFrame();
if (imgOriginal == null)
{
return;
}
imgProcessed = imgOriginal.InRange(new Bgr(0, 0, 150)/*min filter*/, new Bgr(80, 80, 256));
// imgProcessed = imgOriginal.InRange(new Bgr(0, 0, 175)/*min filter*/, new Bgr(100, 100, 256));
imgProcessed = imgProcessed.SmoothGaussian(9);//9
circles = imgProcessed.HoughCircles(new Gray(100), //canny threshhold
new Gray(50), //accumolator threshold
2,//size of image
imgProcessed.Height / 4, //min size in pixels between centers of detected circles
15, //min radios
43)[0];//max radios and get circles from first channel
foreach (CircleF circle in circles)
{
centerList.Add(circle.Center);
// circlesOfBalls.Add(circle);
if (textBox1.Text != "") textBox1.AppendText(Environment.NewLine);
textBox1.AppendText("ball position = x" + centerList[centerList.Count - 1].X +
", y = " + centerList[centerList.Count - 1].Y.ToString().PadLeft(4)
+ "centerList.Count= " + centerList.Count);
// + ", radios = " + centerList[centerList.Count - 1].Radius.ToString("###,000").PadLeft(7))
textBox1.ScrollToCaret();// scrolls the textBox to last line
// draw a small green circle in the center
CvInvoke.cvCircle(imgOriginal, // draw on the original image
new Point((int)circle.Center.X, (int)circle.Center.Y),//center point of circle
3, // radios of circle,
new MCvScalar (0, 255, 0), // draw in green color
-1, //indicates to fill the circle
LINE_TYPE.CV_AA, //smoothes the pixels
0);// no shift
//draw a red circle around the detected object
// if (imgOriginal.Data != null)
imgOriginal.Draw(circle, //current circle
new Bgr(Color.Red), // draw pure red
3);
} // end of for each
// if(imgOriginal.Data != null)
imageBox1.Image = imgOriginal;
}