无法在 EMGU CV 中绘制 SharpGL(openGL wrapper)对象
本文关键字：openGL wrapper 对象 SharpGL 绘制 EMGU CV | 更新日期: 2023-09-27 18:34:51
我一直在使用emgu cv(opencv包装器(从网络摄像头捕获图像，并使用它的功能来处理这些图像。我还检测手并跟踪手的运动...
现在，我需要根据手的位置画一种地球或只是一个物体，对于它，sharpGL非常适合透视变换等等。我的问题是我无法实现这一目标。
我不知道怎么对锐化GL说"你这家伙，在这个手部跟踪窗口中画那个物体"我想做的事情是不可能的吗？我很绝望...任何帮助都会很棒。提前致谢
如果您仍然对我的意思感到困惑，请观看此视频(http://www.youtube.com/watch?v=ccL4t36sVvg(
到目前为止，我刚刚将这段代码 http://blog.damiles.com/2008/10/opencv-opengl/转换为 C#
这是代码片段
private void openGLControl_OpenGLInitialized(object sender, EventArgs e)
{
// TODO: Initialise OpenGL here.
// The texture identifier.
uint[] textures = new uint[1];
// Get the OpenGL object.
OpenGL gl = openGLControl1.OpenGL;
//texture.Create(gl);
// Get one texture id, and stick it into the textures array.
gl.GenTextures(1, textures);
// Bind the texture.
gl.BindTexture(OpenGL.GL_TEXTURE_2D, textures[0]);
// A bit of extra initialisation here, we have to enable textures.
gl.Enable(OpenGL.GL_TEXTURE_2D);
// Specify linear filtering.
gl.TexParameter(OpenGL.GL_TEXTURE_2D, OpenGL.GL_TEXTURE_MIN_FILTER, OpenGL.GL_NEAREST);
gl.TexParameter(OpenGL.GL_TEXTURE_2D, OpenGL.GL_TEXTURE_MAG_FILTER, OpenGL.GL_NEAREST);
gl.PixelStore(OpenGL.GL_UNPACK_ALIGNMENT, 1);
// Set the clear color.
gl.ClearColor(1.0f, 1.0f, 1.0f, 1.0f);
}
private void openGLControl_Resized(object sender, EventArgs e)
{
// TODO: Set the projection matrix here.
// Get the OpenGL object.
OpenGL gl = openGLControl1.OpenGL;
// Set the projection matrix.
gl.MatrixMode(OpenGL.GL_PROJECTION);
// Load the identity.
gl.LoadIdentity();
// Create a perspective transformation.
gl.Perspective(60.0f, (double)Width / (double)Height, 0.01, 100.0);
// Use the 'look at' helper function to position and aim the camera.
gl.LookAt(-5, 5, -5, 0, 0, 0, 0, 1, 0);
// Set the modelview matrix.
gl.MatrixMode(OpenGL.GL_MODELVIEW);
}
最后绘制一个 3D 对象
private void openGLControl_OpenGLDraw(object sender, PaintEventArgs e)
{
// Get the OpenGL object.
OpenGL gl = openGLControl1.OpenGL;
if (capture == null)
{
this.start_capture();
}
if (capture != null)
{
Image<Bgr, Byte> ImageFrame = capture.QueryFrame();
//I'm trying to use some algorithm using the code from sample (sharpGLTextureExample)
//first, I make an Bitmap object that I take from queryframe(convert it to bitmap first)
Bitmap image = new Bitmap(ImageFrame.ToBitmap());
// Clear the color and depth buffer.
gl.Clear(OpenGL.GL_COLOR_BUFFER_BIT | OpenGL.GL_DEPTH_BUFFER_BIT);
//ImageFrame.Draw(new Rectangle(2, 2, 2, 2), new Bgr(Color.Aqua), 2);
// Load the identity matrix.
gl.LoadIdentity();
//then, Lock the image bits (so that we can pass them to OGL).
BitmapData bitmapData = image.LockBits(new Rectangle(0, 0, image.Width, image.Height),
ImageLockMode.ReadOnly, PixelFormat.Format32bppArgb);
gl.BindTexture(OpenGL.GL_TEXTURE_2D, textures[0]);
//gl.TexImage2D(OpenGL.GL_TEXTURE_2D, 0, (int)OpenGL.GL_RGBA, ImageFrame.Width, ImageFrame.Height, 0, OpenGL.GL_RGBA, OpenGL.GL_UNSIGNED_BYTE, ImageFrame);
gl.TexImage2D(OpenGL.GL_TEXTURE_2D, 0, (int)OpenGL.GL_RGBA, ImageFrame.Width, ImageFrame.Height, 0, OpenGL.GL_RGBA, OpenGL.GL_UNSIGNED_BYTE, bitmapData.Scan0);
//gl.Begin(OpenGL.GL_QUADS);
//gl.TexCoord(0, 0); gl.Vertex(-1, -1, 0);
//gl.TexCoord(1, 0); gl.Vertex(1, -1, 0);
//gl.TexCoord(1, 5); gl.Vertex(1, 1, 0);
//gl.TexCoord(0, 1); gl.Vertex(-1, 1, 0);
//gl.End();
//gl.Flush();
//texture.Bind(gl);
//
//CamImageBox.Image = ImageFrame;
}
}
但是输出总是返回白色，上面没有纹理......
我也考虑使用纹理类，但没有用。因为没有输入参数是帧的方法......
从您的代码和 http://basic4gl.wikispaces.com/2D+Drawing+in+OpenGL 的帮助下，我让 SharpGL 显示来自 EmguCV 的视频
public partial class FormSharpGLTexturesSample : Form
{
Capture capture;
public FormSharpGLTexturesSample()
{
InitializeComponent();
// Get the OpenGL object, for quick access.
SharpGL.OpenGL gl = this.openGLControl1.OpenGL;
// A bit of extra initialisation here, we have to enable textures.
gl.Enable(OpenGL.GL_TEXTURE_2D);
gl.Disable(OpenGL.GL_DEPTH_TEST);
// Create our texture object from a file. This creates the texture for OpenGL.
capture = new Capture(@"Video file here");
}
private void openGLControl1_OpenGLDraw(object sender, RenderEventArgs e)
{
// Get the OpenGL object, for quick access.
SharpGL.OpenGL gl = this.openGLControl1.OpenGL;
int Width = openGLControl1.Width;
int Height = openGLControl1.Height;
gl.Clear(OpenGL.GL_COLOR_BUFFER_BIT);
gl.LoadIdentity();
var frame = capture.QueryFrame();
texture.Destroy(gl);
texture.Create(gl, frame.Bitmap);
// Bind the texture.
texture.Bind(gl);
gl.Begin(OpenGL.GL_QUADS);
gl.TexCoord(0.0f, 0.0f); gl.Vertex(0, 0, 0);
gl.TexCoord(1.0f, 0.0f); gl.Vertex(Width, 0, 0);
gl.TexCoord(1.0f, 1.0f); gl.Vertex(Width, Height, 0);
gl.TexCoord(0.0f, 1.0f); gl.Vertex(0, Height, 0);
gl.End();
gl.Flush();
}
// The texture identifier.
Texture texture = new Texture();
private void openGLControl1_Resized(object sender, EventArgs e)
{
SharpGL.OpenGL gl = this.openGLControl1.OpenGL;
// Create an orthographic projection.
gl.MatrixMode(MatrixMode.Projection);
gl.LoadIdentity();
// NOTE: Basically no matter what I do, the only points I see are those at
// the "near" surface (with z = -zNear)--in this case, I only see green points
gl.Ortho(0, openGLControl1.Width, openGLControl1.Height, 0, 0, 1);
// Back to the modelview.
gl.MatrixMode(MatrixMode.Modelview);
}
}
我希望它有所帮助。
经过一些实验，我可以使用TexImage2D，但只能使用宽度和高度为2次幂的图像。
而不是：
var frame = capture.QueryFrame();
texture.Destroy(gl);
texture.Create(gl, frame.Bitmap);
可以用下面的块代替它来更新图片的数据。我想知道如何消除调用 Resize 的需要。
var frame = capture.QueryFrame();
frame = frame.Resize(256, 256, Emgu.CV.CvEnum.INTER.CV_INTER_NN);
Bitmap Bitmap = frame.Bitmap;
BitmapData bitmapData = Bitmap.LockBits(new Rectangle(0, 0, Bitmap.Width, Bitmap.Height),
ImageLockMode.ReadOnly, PixelFormat.Format24bppRgb);
gl.BindTexture(OpenGL.GL_TEXTURE_2D, textures[0]);
gl.TexImage2D(OpenGL.GL_TEXTURE_2D, 0, OpenGL.GL_RGBA, Bitmap.Width, Bitmap.Height, 0, OpenGL.GL_BGR, OpenGL.GL_UNSIGNED_BYTE, bitmapData.Scan0);
gl.TexParameter(OpenGL.GL_TEXTURE_2D, OpenGL.GL_TEXTURE_MIN_FILTER, OpenGL.GL_LINEAR); // Required for TexImage2D
gl.TexParameter(OpenGL.GL_TEXTURE_2D, OpenGL.GL_TEXTURE_MAG_FILTER, OpenGL.GL_LINEAR); // Required for TexImage2D