Develop Reference

Displaying editable image in c#

I want to display an image (.tif, gray value 16 bit) which is editable for the user via sliders. The displayed image should directly react to the changes, so the user knows what he's doing to the image.
Currently I only seem to be creating new files with every change and displaying the latest one, which is a terrible solution.
My idea would be to load the original pixeldata, put it in some sort of temporary file which isn't and won't be saved, then saving the parameters of the sliders and when hitting save applying the parameters to the original image (since in the end the filter is used on an intire set of images).

An Image is not a File. If might be that you display the Image that is in a file, but once you've loaded the file into an Image object don't ever use the file again, until the edited image needs to be saved in a file.
You say you want to display an image. As you are using winforms, I assume you are using a PictureBox control. If not, you have a class that you order to display an Image.
Image imageToDisplay = GetImageToDisplay();
this.PictureBox1.Image = imageToDisplay;
GetImageTodisplay will read the file and return it as an Image
System.Drawing.Image GetImageToDisplay()
{
FileStream imageStream = new FileStream(this.GetImageFileName(), FileMode.Open);
System.Drawing.Image image = new Image(imageStream);
return image;
}
Apparently you also have sliders. You don't mention the class of your sliders, but apparently it is an object that notifies your form about a new slider value.
void OnSliderValueChanged(object sender, int sliderValue)
{
Image displayedImage = this.PictureBox1.Image;
this.ProcessSliderChanged(image, sliderValue);
}
Until now I don't see the creation of a new file. So this should be in ProcessSliderChange. Luckily that is a function you created yourself. All you have to do is change the image according to your new slider value. Don't do anything with file handling and you won't get a new file
void ProcessSliderChange(System.Drawing.Image image, int sliderValue)
{ // what do you want to do with the image?
// make it darker? move it? change contrast?
}
Unfortunately the Image class doesn't have a lot of functions to edit images, I assume you have a library with functions that act on System.Drawing.Image objects. Just use those functions to change your Image.

Powerpoint exporting shapes same size

I am trying to convert pptx to html using c# by exporting every picture as an image but although I've tried all different PpExportMode's, I could not export the shapes with the same size. For instance, an image that's height and width are both 0,37 cm in powerpoint (it's equal to 13.984251969), becomes 20*20 pixel when I exported it. Does anyone know how can I save these shapes with the same size ? I've tried these;
shape.Export(exportPath + "\\" + fileName, PpShapeFormat.ppShapeFormatPNG,(int)slide.Master.Width,(int)slide.Master.Height, PpExportMode.ppScaleToFit);
shape.Export(exportPath + "\\" + fileName, PpShapeFormat.ppShapeFormatPNG,0,0, PpExportMode.ppScaleToFit);
with different PpExportMode's.
Thanks in advance.

Changing the image of the pictureBox in the code

In my project on WindowsForms (VS13) I have a pictureBox. How can I change the image of it in the code?
pictureBox1.Image = //???
For example, for the the textBox I can do it like:
richTextBox1.Text = someVariable.ToString();
The image are exists in my project's folder.

If you add the picture to you projects resources you can change the image like this
pictureBox1.Image = Properties.Resources.picture1;
Hope this helps

The .Image property set a image as object, you can specify the path o url of the image with ImageLocation
pictureBox1.ImageLocation = "PATH O URL OF THE IMAGE";

saving C# winforms Panel or PictureBox with animated elements to gif file?

How to save C# winforms Panel or PictureBox with animated elements to gif file?
I also tried to do it like this
pictureBox2.Image.Save(System.IO.Path.Combine(
Environment.GetFolderPath(Environment.SpecialFolder.DesktopDirectory), "1.gif"),
System.Drawing.Imaging.ImageFormat.Gif);
but it save just static image without animation.

Take a look at this. The Bumpkit library he uses is open source, so you can just include the file you need in your solution.

c# Image from file close connection

I display an image using c# in a pictureBox. Then I want to change the image's name. I can't because I get that the image is being used by another process.
I open the image this way
Image image1 = Image.FromFile("IMAGE LOCATION"); ;
pictureBox1.Image = image1;
Then try to change it's name this way and I get an IO exception saying " The process cannot access the file because it's being used by another process.
System.IO.File.Copy(#"OldName", #"NewName"); //copy changes name if paths are in the same folder
Isn't the object image1 holding the image? Why is the file still locked by the previous process? Any suggestions would be appreciated. Many thanks!

Have a look at this question: Free file locked by new Bitmap(filePath)
To free the lock you need to make a copy of the bits:
Image img;
using (var bmpTemp = new Bitmap("image_file_path"))
{
img = new Bitmap(bmpTemp);
}

Yes, picture box control locking IO file on the disk in that way.
If you want to rename linked file, you can:
or dispose picture box, and after rename the file (if this is suitable for your app)
or assign to the picture box a copy/clone of the image.

You can try this:
Image image1 = null;
using(FileStream stream = new FileStream("IMAGE LOCATION", FileMode.Open))
{
image1 = Image.FromStream(stream);
}
pictureBox1.Image = image1
;

you need to dispose your image:
Image image1 = Image.FromFile("IMAGE LOCATION"); ;
pictureBox1.Image = image1;
image1.Dispose();
the do the move.

this solution solved my problem. I was using a picturebox and loading its image directly from the disk without an intermediate image file. when I was done I was doing a "picturebox.dispose" and that did not free up the image file and I couldn't delete it because "file in use by vshost". I had to explicitly create an image variable (IE dim MyImage as image) and then first load the image into the image variable, then load MyImage into the picturebox. by having a reference to the image I could do a MyImage.dispose. That closed the link between vshost and the image and I was able to programmatically delete it.