Develop Reference

EmguCV never open ".jpg" file but open only ".tif" files..Why?

I am using EmguCV in Visual Studio 2022 and I am simple trying to read and open my image but it only opens .tif image files not .jpg or any other file...
When I try to open any .jpg file it gives me an exception openCV:index out of bound
Here:
I also debugged it and find something like it is not reading file when I passed it to EmguCV image structure "Image<Bgr,byte> imgFile=new Image<Bgr,byte>(filename)"
while it is loading file from dialogue but not passing forward from this structure.
Here's the Debug SS:
Code:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using Emgu;
using Emgu.CV;
using Emgu.CV.Structure;
using Emgu.CV.Util;
namespace test_EmguCV
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void openToolStripMenuItem_Click(object sender, EventArgs e)
{
try
{
OpenFileDialog ofd = new OpenFileDialog();
if (ofd.ShowDialog() == DialogResult.OK)
{
Image<Bgr, byte> imgFile = new Image<Bgr, byte>(ofd.FileName);
pictureBox1.Image = imgFile.Bitmap;
}
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
}
private void exToolStripMenuItem_Click(object sender, EventArgs e)
{
this.Close();
}
}
}
Another Imp:
My friend is also doing the same work with me and he is using the same ide same mehtods same references same dll files but his is running fine but not of mine..

I just tried your code snippet in a new Form and I can say that I can successfully load a .jpg image and display it in a PictureBox. Make sure your image is not corrupted in the first place.
Here's my code:
private void button1_Click(object sender, EventArgs e)
{
try
{
OpenFileDialog ofd = new OpenFileDialog();
if (ofd.ShowDialog() == DialogResult.OK)
{
Image<Bgr, byte> imgFile = new Image<Bgr, byte>(ofd.FileName);
pictureBox1.Image = imgFile.ToBitmap();
}
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
}
Note that it's imgFile.ToBitmap(), not imgFile.Bitmap()
Also I would suggest you to switch to Mat instead of Image<>. More info from OpenCV docs
With Mat the code to get the image is as easy as:
Mat imgFile = new Mat(ofd.FileName);
More info about Mat in EmguCV here

C# crashes with 'Parameter is not valid.' when setting PictureBox.image to Bitmap in Application.Run(new Control_Panel())

After I connect to USB camera, and read a frame, and convert to bitmap,
it crashes after I write bitmap to PictureBox.
I'm developing a Visual Studio 2017 Pro C# Windows forms project.
Also, if I debug process_video_NewFrame() and step through it, then crash 'Parameter is not valid.' occurs at line in Program.cs:
Application.Run(new Control_Panel()).
Control_Panel.cs
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Drawing;
using Accord.Video;
using Accord.Video.DirectShow;
namespace ACCORD_WindowsFormsApp9
{
public partial class Control_Panel : Form
{
VideoCaptureDevice videoSource;
Bitmap bitmap;
public Control_Panel()
{
InitializeComponent();
}
private void button_Start_Frame_Captcha_Click(object sender, EventArgs e)
{
var videoDevices = new FilterInfoCollection(FilterCategory.VideoInputDevice);
videoSource = new VideoCaptureDevice(videoDevices[0].MonikerString);
videoSource.NewFrame += new NewFrameEventHandler(process_video_NewFrame);
videoSource.Start();
}
// The video_NewFrame used in the example above could be defined as:
private void process_video_NewFrame(object sender, NewFrameEventArgs eventArgs)
{
// get new frame
bitmap = eventArgs.Frame;
System.Windows.Forms.Application.DoEvents();
this.pictureBoxLatestCameraFrame.Image = bitmap;
}
private void button_Stop_Frame_Captcha_Click(object sender, EventArgs e)
{
videoSource.SignalToStop();
}
}
}
Program.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace ACCORD_WindowsFormsApp9
{
static class Program
{
/// <summary>
/// The main entry point for the application.
/// </summary>
[STAThread]
static void Main()
{
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
Application.Run(new Control_Panel());
}
}
}

Fixed! Thanks, Sriram. Keep that crystal ball polished... New to Bitmap, I mistakenly assumed it was an image, when actually it is an object, and so requires a new instance each iteration, ie...
private void process_video_NewFrame(object sender, NewFrameEventArgs eventArgs)
{
// Ax previous Bitmap object:
if( loops > 0 )
{
camera_snapshot_bitmap.Dispose();
}
// get new frame
camera_snapshot_bitmap = new Bitmap( eventArgs.Frame );
//ax System.Windows.Forms.Application.DoEvents();
this.pictureBoxLatestCameraFrame.Image = camera_snapshot_bitmap;
++loops;
Console.WriteLine("Loops " + loops );
}

EmguCV capture error: Cannot implicitly convert type 'Emgu.CV.Mat' to 'Emgu.CV.Image<Emgu.CV.Structure.Bgr,byte>

I am using EmguCV with C#, I am facing a problem when I want to grab frames from my web cam, red underline appears on statement:
imgOrg = capturecam.QueryFrame();
error: Cannot implicitly convert type 'Emgu.CV.Mat' to 'Emgu.CV.Image
how can I solve this problem?
my code:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using Emgu.CV;
using Emgu.CV.CvEnum;
using Emgu.CV.Structure;
using Emgu.CV.UI;
namespace test2
{
public partial class Form1 : Form
{
Image<Bgr, Byte> imgOrg; //image type RGB (or Bgr as we say in Open CV)
private Capture capturecam;
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
try
{
capturecam = new Capture();
}
catch (NullReferenceException exception)
{
MessageBox.Show(exception.Message);
return;
}
Application.Idle += new EventHandler(ProcessFunction);
}
private void ProcessFunction(object sender, EventArgs arg)
{
imgOrg = capturecam.QueryFrame(); // error line
imageBox1.Image = imgOrg;
}
}
}

This statement works:
Image<Bgr, Byte> img = mat.ToImage<Bgr, Byte>();

Try this:
imgOrg = capturecam.QueryFrame().ToImage<Bgr, Byte>();
Look here:
how to convert mat to image in (Emgu CV version 3) in c#?
Or change your Image variable to Mat:
Mat imgOrg = new Mat(); // instead of: Image<Bgr, Byte> imgOrg;
imgOrg = capture.QueryFrame();
imageBox1.Image = imgOrg;

imgOrg = new Image(capturecam.QueryFrame().Bitmap);
This Code Worked For me. I hope working for you too.

This is pretty straight forward. This works in Emgu CV 3.3++.
vidCap = new VideoCapture([filename or webcam device]);
Mat mat = new Mat();
vidCap.Read(mat); //This calls Grab() as grabbing a frame and then Retrieve();
imageBox1.Image = mat.Bitmap;

Image FRAME2= frame.ToImage();

Reference the example, the QueryFrame() not be used anymore at EmguCV 3.0. it be replaced by Retrieve() function.
Sample as shown below:
Mat frame = new Mat();
cap.Retrieve(frame, 0);
Mat grayFrame = new Mat();
CvInvoke.CvtColor(frame, grayFrame, ColorConversion.Bgr2Gray);
imageBox1.Image = frame;
imageBox2.Image = grayFrame;

Implement and trigger on detected motion

How can I implement a simple motion-detection method using EMGUCV? I have searched for applicable examples, but the only solutions I found were too complicated to implement.
Is there a way I can implement a simple method to detect motion in order to trigger something in my application?

Convert a single frame to grayscale.
Convert a new frames from real time into grayscale.
Make abstractions between the first frame and new frame from real time.
The result of this is a third, new frame comprised of the differences between the first two. Use erosion and thresholding for that to get a frame with white representing the motioned section and black representing the rest of the space.
Here is a piece of code:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using Emgu.CV;
using Emgu.CV.UI;
using Emgu.CV.CvEnum;
using Emgu.CV.Structure;
using System.Diagnostics;
using System.IO;
using System.Data.SqlClient;
using System.Data.SqlServerCe;
using System.Drawing.Imaging;
namespace ptuxiakh___
{
public partial class Form1 : Form
{
Capture _capture = new Capture();
Capture capture2 = new Capture();
Image<Bgr, Byte> FirstImage = new Image<Bgr, Byte>(640, 480);
Image<Bgr, Byte> RealTimeImage = new Image<Bgr, Byte>(640, 480);
Image<Gray, Byte> des = new Image<Gray, Byte>(640, 480);
Image<Gray, Byte> thres = new Image<Gray, Byte>(640, 480);
Image<Gray, Byte> eroded = new Image<Gray, Byte>(640, 480);
bool baground = false;
private void Background()
{
try{
FirstImage = _capture.QueryFrame();
background = true;
}
catch(Exception e)
{
baground = false;
}
}
private void Tracking(object sender, EventArgs e)
{
if (baground == true)
{
RealTimeImage = capture2.QueryFrame();
CvInvoke.cvAbsDiff(FirstImage.Convert<Gray, Byte>(), RealTimeImage.Convert<Gray, Byte>(), des);
CvInvoke.cvThreshold(des, thres, 20, 255, THRESH.CV_THRESH_BINARY);
CvInvoke.cvErode(thres, eroded, IntPtr.Zero, 2);
}
else
{
Background(); // At first trying to get a static frame for
// abstraction with real time frame
}
}
private void StartButton_Click(object sender, EventArgs e)
{
Application.Idle += new EventHandler(Tracking);
}
private void Stopbutton_Click(object sender, EventArgs e)
{
Application.Idle -= new EventHandler(Tracking);
}
//eroded will be your relust

UI Freezes while processing frames from Kinect using EmguCV in WPF C# Application

I am working on a project which involves extracting features from color and depth frames from Kinect Camera. The problem I am facing is that whenever I try displaying 2 Images, the UI hangs. When I tried debugging, the depthFrame and colorFrame were coming as null. If enable only the color steam then both colorImage and featureImage1 are displayed properly and if I enable only the depth stream, it works as it should. But when I enable them both, the UI hangs. I have no idea what is causing the problem. I have the following the following code for my Kinect Application. What is the cause of this problem and how can I fix it?
Config: Windows 8 Pro 64bit, 2Ghz Core2Duo, VisualStudio 2012 Ultimate, EmguCV 2.4.0.
using System;
using System.Collections.Generic;
using System.Drawing;
using System.Linq;
using System.Runtime.InteropServices;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
using Microsoft.Kinect;
using Emgu.CV;
using Emgu.CV.WPF;
using Emgu.CV.Structure;
using Emgu.Util;
namespace features
{
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
}
private Image<Bgra, Byte> cvColorImage;
private Image<Gray, Int16> cvDepthImage;
private int colorWidth = 640;
private int colorHeight = 480;
private int depthWidth = 640;
private int depthHeight = 480;
private static readonly int Bgr32BytesPerPixel = (PixelFormats.Bgr32.BitsPerPixel + 7) / 8;
private byte[] colorPixels;
private byte[] depthPixels;
private short[] rawDepthData;
private bool first = true;
private bool firstDepth = true;
Image<Bgra, byte> image2;
private void Window_Loaded(object sender, RoutedEventArgs e)
{
kinectSensorChooser.KinectSensorChanged += new DependencyPropertyChangedEventHandler(kinectSensorChooser_KinectSensorChanged);
}
void kinectSensorChooser_KinectSensorChanged(object sender, DependencyPropertyChangedEventArgs e)
{
KinectSensor oldSensor = (KinectSensor)e.OldValue;
KinectStop(oldSensor);
KinectSensor _sensor = (KinectSensor)e.NewValue;
_sensor.ColorStream.Enable(ColorImageFormat.RgbResolution640x480Fps30);
_sensor.DepthStream.Enable(DepthImageFormat.Resolution640x480Fps30);
_sensor.DepthFrameReady += new EventHandler<DepthImageFrameReadyEventArgs>(_sensor_DepthFrameReady);
_sensor.ColorFrameReady += new EventHandler<ColorImageFrameReadyEventArgs>(_sensor_ColorFrameReady);
_sensor.DepthStream.FrameHeight);
try
{
_sensor.Start();
}
catch
{
kinectSensorChooser.AppConflictOccurred();
}
}
void KinectStop(KinectSensor sensor)
{
if (sensor != null)
{
sensor.Stop();
}
}
private void Window_Closed(object sender, EventArgs e)
{
KinectStop(kinectSensorChooser.Kinect);
}
void _sensor_ColorFrameReady(object sender, ColorImageFrameReadyEventArgs e)
{
using (ColorImageFrame colorFrame = e.OpenColorImageFrame())
{
if (colorFrame == null) return;
if (first)
{
this.colorPixels = new Byte[colorFrame.PixelDataLength];
first = false;
}
colorFrame.CopyPixelDataTo(this.colorPixels); //raw data in bgrx format
processColor();
}
}
void _sensor_DepthFrameReady(object sender, DepthImageFrameReadyEventArgs e)
{
using (DepthImageFrame depthFrame = e.OpenDepthImageFrame())
{
if (depthFrame == null) return;
if (firstDepth)
{
this.rawDepthData = new short[depthFrame.PixelDataLength];
firstDepth = false;
}
depthFrame.CopyPixelDataTo(rawDepthData);
processDepth();
}
}
private void processColor(){...}
private void processDepth(){...}
}
}
The processDepth function is as follows. I am just making an Image from the RAW depth data.
private void processDepth() {
GCHandle pinnedArray = GCHandle.Alloc(this.rawDepthData, GCHandleType.Pinned);
IntPtr pointer = pinnedArray.AddrOfPinnedObject();
cvDepthImage = new Image<Gray, Int16>(depthWidth, depthHeight, depthWidth << 1, pointer);
pinnedArray.Free();
depthImage.Source = BitmapSourceConvert.ToBitmapSource(cvDepthImage.Not().Bitmap);
}
The processColor function is as follows. Here just for the sake of it, I am trying to display the cloned image instead of extracting features, just to check the lag. When both streams are enabled (color and depth) the following function displays the colorImage properly, but as soon as I uncomment the commented lines, the UI hangs.
private void processColor() {
GCHandle handle = GCHandle.Alloc(this.colorPixels, GCHandleType.Pinned);
Bitmap image = new Bitmap(colorWidth, colorHeight, colorWidth<<2, System.Drawing.Imaging.PixelFormat.Format32bppRgb, handle.AddrOfPinnedObject());
handle.Free();
cvColorImage = new Image<Bgra, byte>(image);
image.Dispose();
BitmapSource src = BitmapSourceConvert.ToBitmapSource(cvColorImage.Bitmap);
colorImage.Source = src;
//image2 = new Image<Bgra, byte>(cvColorImage.ToBitmap()); //uncomment and it hangs
//featureImage1.Source = BitmapSourceConvert.ToBitmapSource(image2.Bitmap); //uncomment and it hangs
}

I see code that do a lot of work in event handlers. I almost certain that handlers is called in GUI thread. I suggest you to extract your code to the background thread routine. Don't forget that updating of the Form's controls (depthImage and controlImage) should be done using BeginInvoke method of the parent form,