I'm using the Emgu library for integrating the open CV webcam features in C#.
I use this code for choosing the capture device and setting its size:
camera = new Capture(0);
camera.SetCaptureProperty(CAP_PROP.CV_CAP_PROP_FRAME_WIDTH, videoSettings.width);
camera.SetCaptureProperty(CAP_PROP.CV_CAP_PROP_FRAME_HEIGHT, videoSettings.height);
Then I display it in an imageBox like this: imageBox1.Image = camera.QueryFrame();
Then to capture a snapshot of the current frame I use this code:
Image<Bgr, byte> snapshot = camera.QueryFrame();
snapshot.Save("snapshot.jpg");
Though I would want to be able to save the snapshot at a higher resolution than the preview window.
But the problem is that as far as I know I can't create a new "Capture" object using the same webcamera. So I'm wondering if it is maybe possible to set the camera.setCaptureProperty height and width to let's say 1028x720 but then in some way crop it for displaying it in the imageBox with the resolution of 514x360?
Or is there any other way to do this?
I solved this by using
imageBox1.SizeMode = PictureBoxSizeMode.StretchImage;
I solved this by using the Resize() method in QueryFrame()
currentFrame = grabber.QueryFrame().Resize(320, 240, Emgu.CV.CvEnum.INTER.CV_INTER_CUBIC);
Related
I use the imagebox to display a image(imgWidth:19200, imgHeight:260),and my code is:
imageBox = new ImageBox();
imageBox.Size = new Size(imgWidth, imgHeight);
imageBox.Dock = DockStyle.Fill;
MainSplitContainer.Panel1.Controls.Add(imageBox);
imageBox.Image = new Image<Bgr, byte>("2.bmp");
But the displayed image width is only about 15000, and the right part of the image can not be displayed. How can I display the full image?
It is possible that an ImageBox won't do more than 15,000 pixels in width. However, have you tried setting the functional mode to Pan and Zoom? Maybe that will get you there.
Doug
I built a UWP XAML control that acts as a barcode/qrcode scanner using the zxing.net library (http://zxingnet.codeplex.com/). The control works fine, it previews the camera on the device and then captures a frame and let zxing process it. All a user has to do is to place it in a page and tell it what type of barcode to scan.
I am just facing one problem: How can I limit the scan area to the center of the captured frame? Sometimes there are multiple barcodes in the image and the library returns a result from one of the barcodes but I am interested in the barcode that is in the middle of the frame.
Is this possible with zxing.net? If so, how can I limit the scan area?
I don't know what code are you using. But I can give a hint based on my UWP barcode scanner
Inside CapturePhotoFromCameraAsync() Task you can find code that take "screenshot" frame from camera:
VideoFrame videoFrame = new VideoFrame(BitmapPixelFormat.Bgra8, (int)_width, (int)_height);
await mediaCapture.GetPreviewFrameAsync(videoFrame);
You can get there SoftwareBitmap and eben convert to WritableBitmap.
SoftwareBitmap sb = videoFrame.SoftwareBitmap;
WriteableBitmap bitmap = new WriteableBitmap(sb.PixelWidth, sb.PixelHeight);
But now there is another question how to crop WriteableBitmap (you can find solution on SO or MSDN - it's not short) and how to convert back to SoftwareBitmap.
Hi so I'm making an app for Windows 10 that requires a user to choose an image and it's going to crop the image to 310*128. I got the file picker code already. But I want to know how to actually crop and save the image and display in image box. I already have the xaml page done
With Lumia Imaging SDK you can both crop the selected image and resize the image. In this answer I assume you actually want to crop, but from the text I could just as well guess you really just want to resize.
For crop, use the CropEffect from Lumia.Imaging.Transforms. Set the CropArea property on it to the object, and then render it. If you are rendering straight to the XAML page I recommend using a SwapChainPanel object in XAML and a SwapChainPanelRenderer to render on it.
Given that you are loading a StorageFile and rendering to a SwapChainPanel your code might look like something like this:
StorageFile file = ...
using (var source = new StorageFileImageSource(file))
using (var crop = new CropEffect(source, new Rect(0, 0, 310, 128))
using (var renderer = new SwapChainPanelRenderer(crop, YourSwapChainPanel))
{
await renderer.RenderAsync();
}
I am currently working on a C# application that aims to do some computation and output graphs in a pdf file.
I use the Zedgraph library to draw my graphs so something like graphPane.AddCurve(PointPairList). Now I tried to output these graphs to pdf file via MigraDoc package.
Currently, I have a script that map the Zedgraph to bitmap then paste it on the pdf file. So something like this:
private Bitmap getBitMap()
{
ZedGraphControl graph = new ZedGraphControl();
newGraph = graphPane.Clone();
SizeF s = new SizeF(3.5f, 4.5f);
newGraph.Scale(s);
newGraph.DrawToBitmap(bit, new Rectangle(0, 0, newGraph.Width, newGraph.Height));
return bit;
}
The problem is that this give me a slightly pixellated image on the pdf page. And I need this graph to be in a very high quality. So are there anything I can change the improve the quality or do i have to change my entire approach for such thing.
Thank you so much in advance.
By default a Bitmap you create has your current screen resolution which could be as low as 75dpi, more common 96dpi; more modern monitors have 120dpi or more, but a good print quality starts 150dpi. For really crips images you want 300dpi and to allow zooming you may want to have 600dpi or more..
So you need to create and fill a bitmap with a larger size and take control of its dpi resolution.
Assuming your size of 3.5f x 4.5f is inches, for 300dpi you need a Bitmap with 1050 x 1350 pixels.
So you should create such a Bitmap..:
Bitmap bmp = new Bitmap(1050, 1350);
..and set the resolution:
bmp.SetResolution(300, 300);
To fill it up your control must have the same size:
newGraph.ClientSize = bmp.Size;
Now DrawToBitmap should create an image that is crisp and fit to zoom in..
Note that it does not matter if the control is too large to fit on the screen; DrawToBitmap will still work.
Update In addidtion to a sufficient resolution it is of interest to draw quality lines etc.. A speciality of ZedGraph is that one can turn on Antialiasing, either for individual lines:
curve_x.Line.IsAntiAlias = true;
or other elements:
myPane.XAxis.Scale.FontSpec.IsAntiAlias = true;
or the whole Chart:
zedGraphControl1.IsAntiAlias = true;
All examples are taken from this post.
I know there's been many topics similar to this one but none of them had a precise answer to what I'm searching for so please if anybody knows, and also I'm doing it in C#.
You all probably know (FPS) games and on the game screen with resolution say 1024x768 i need to find a red rectangle(which is the enemy) and move the mouse to it.
So my main problem is to find that red rectangle. OK so here's what I've tried so far:
I've tried the AForge and ran out of memory:
ExhaustiveTemplateMatching tm = new ExhaustiveTemplateMatching(0);
TemplateMatch[] matchings = tm.ProcessImage(image1.Clone(r,
System.Drawing.Imaging.PixelFormat.Format24bppRgb), image2);
I've used CopyfromScreen to create a image1 and image2 is a template I have.
I've tried the LockBits, so I can create the 2 dimensional code array for a bitmap and find the code for color red and try to ID if it's a rectangle but the idea seems very complicated been stuck here for a 4 days now.
The web is full of info on this but the more I go into the more I get confused :(
Anyway please ppl help me out here:
Well, first I need to say that this will be probably slow, so if the red rectangle is moving fast, you will need some other solution. C++, CUDA, etc...
First:
Save a image of the red rectangle.
Define the area of possible locations of the red rectangle.
Steps:
Capture the game image (you can use Graphics CopyFromScreen).Copy only the area that the red rectangle might be, to reduce processing time.
Use EmguCV MatchTemplate to find the position of the red
rectangle.
Move the mouse to the position.
Some thread sleep and Repeat 1...
To process the image use EmguCV
To control the mouse use MouseKeyboardActivityMonitor
Speedup note: EmguCV have some CUDA support now, so you can try to use the CUDA version of the method.
//You can check if a 8bpp image is enough for the comparison,
//since it will be much more faster. Otherwise, use 24bpp images.
//Bitmap pattern = "YOUR RED RECTANGLE IMAGE HERE!!"
Point location = Point.Empty;
//source is the screen image !!
Image<Bgr, Byte> srcBgr = new Image<Bgr, Byte>(source);
Image<Bgr, Byte> templateBgr = new Image<Bgr, Byte>(pattern);
Image<Gray, Byte> src;
Image<Gray, Byte> template;
src = srcBgr.Convert<Gray, Byte>();
template = templateBgr.Convert<Gray, Byte>();
Image<Gray, float> matchFloat;
matchFloat = src.MatchTemplate(template, TM_TYPE.CV_TM_CCOEFF_NORMED);
if (debug)
{
//matchFloat.Save(#"match.png");
//Process.Start(#"D:\match.png");
}
//Gets the max math value
double max;
double[] maxs, mins;
Point[] maxLocations, minLocations;
matchFloat.MinMax(out mins, out maxs, out minLocations, out maxLocations);
max = maxs[0];
if (max > threshold)
{
location = maxLocations[0];
//Point the mouse... Do your stuff