draw rectangle over top of background image on panel with pen

I have a question about this method Sergey. As stated in the original problem above, I would like for this to scan the image in a few different sections and draw around those sections which have a certain pixel value higher than a threshold set. It is possible to do that with this method, right?

I think this may be way too advanced for me - i'm just a newbie. Don't you think it is better for a newbie to not worry about performance so much and just use the Get / Set pixels as they are easier?

so, can I go from the lockpixel into a new method to open and draw that image in a panel with a buttonclick method? like, how do i get to see the image with the rectangle drawn on it from this point?

hey! how's this Sergey public Form1() { InitializeComponent(); } private void LockUnlockBitsExample(PaintEventArgs e) { Bitmap myImage = new Bitmap("C:\\Users\\jason\\Documents\\IProject\\code\\imageAlign\\imageAlign\\bin\\Debug\\good.jpg"); // Lock the bitmap's bits. Rectangle rect = new Rectangle(0, 0, myImage.Height, myImage.Width); System.Drawing.Imaging.BitmapData bmpData = myImage.LockBits(rect, System.Drawing.Imaging.ImageLockMode.ReadWrite, myImage.PixelFormat); // Get the address of the first line. IntPtr ptr = bmpData.Scan0; // Declare an array to hold the bytes of the bitmap. int bytes = Math.Abs(bmpData.Stride) * myImage.Height; byte[] rgbValues = new byte[bytes]; // Copy the RGB values into the array. System.Runtime.InteropServices.Marshal.Copy(ptr, rgbValues, 0, bytes); // Set every third value to 255. A 24bpp bitmap will look red. for (int counter = 2; counter < rgbValues.Length; counter += 3) rgbValues[counter] = 255; // Copy the RGB values back to the bitmap System.Runtime.InteropServices.Marshal.Copy(rgbValues, 0, ptr, bytes); // Unlock the bits. myImage.UnlockBits(bmpData); // Draw the modified image. e.Graphics.DrawImage(myImage, 0, 150); } private void button1_Click(object sender, EventArgs e) { openFileDialog1.Filter = "JPEG IMAGES|*.jpg"; openFileDialog1.InitialDirectory = "C:\\Users\\jason\\Documents\\IProject\\code\\imageAlign\\imageAlign\\bin\\Debug"; openFileDialog1.Title = "Open Image"; if (openFileDialog1.ShowDialog() == System.Windows.Forms.DialogResult.OK) { panel1.BackgroundImage = Image.FromFile(openFileDialog1.FileName); panel1.Invalidate(); } Bitmap myImage; myImage = (Bitmap)Image.FromFile(openFileDialog1.FileName); panel1.BackgroundImage = myImage; // Array for keeping the sums of each row of pixels float[] resultArray = new float[myImage.Height]; // Populate the array with data from each row of pixels, using the brightness value for (int i = 0; i < myImage.Height; i++) { float value = 0; for (int j = 0; j < myImage.Width; j++) { value += myImage.GetPixel(j, i).GetBrightness();//get colour of pixel and that Hue-Saturation-Brightness values } resultArray[i] = value; } }

I ran it - it ran ok and loaded the image. but are the lockpicks and image display linked. they seem separate and unrelated. So, I run the lockpicks ok, but then run the buttonclick as a separate thing. "better move it to the question where you can format it" it was in the 'Have a Question or Comment'link. Is that wrong?