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Image is not drawn at the correct spot

Bitmap image = ReadBitmap("image.png");
Bitmap imageCopy = new Bitmap(image);
Bitmap canvas = new Bitmap(imageCopy.Width+100, imageCopy.Height);
// From this bitmap, the graphics can be obtained, because it has the right PixelFormat
using(Graphics g = Graphics.FromImage(canvas))
{
// Draw the original bitmap onto the graphics of the new bitmap
g.DrawImage(image, 0, 0);
}
// Use tempBitmap as you would have used originalBmp
InputPictureBox.Image = image;
OutputPictureBox.Image = canvas;
I haven't understood the output of this c# code.
The original image is not placed at the correct position. It should have been at (0, 0).
Also, I need a black background.
So, what is going on and how to correct this?

You are loading an Image, then a copy of this source is created using:
Bitmap bitmap = new Bitmap();
When you create a copy of an Image this way, you sacrifice/alter some details:
Dpi Resolution: if not otherwise specified, the resolution is set to the UI resolution. 96 Dpi, as a standard; it might be different with different screen resolutions and scaling. The System in use also affects this value (Windows 7 and Windows 10 will probably/possibly provide different values)
PixelFormat: If not directly copied from the Image source or explicitly specified, the PixelFormat is set to PixelFormat.Format32bppArgb.
From what you were saying, you probably wanted something like this:
var imageSource = Image.FromStream(new MemoryStream(File.ReadAllBytes(#"[SomeImageOfLena]"))), true, false)
var imageCopy = new Bitmap(imageSource.Width + 100, imageSource.Height, imageSource.PixelFormat))
imageCopy.SetResolution(imageSource.HorizontalResolution, imageSource.VerticalResolution);
using (var g = Graphics.FromImage(imageCopy)) {
g.Clear(Color.Black);
g.CompositingMode = CompositingMode.SourceCopy;
g.InterpolationMode = InterpolationMode.HighQualityBicubic;
g.DrawImage(imageSource, (imageCopy.Width - imageSource.Width) / 2, 0);
pictureBox1.Image?.Dispose();
pictureBox2.Image?.Dispose();
pictureBox1.Image = imageSource;
pictureBox2.Image = imageCopy;
}
This is the result:
(The upper/lower frame black color is actually the Picturebox background color)
When the original Image Dpi Resolution is different from the base Dpi Resolution used when creating an Image copy with new Bitmap(), your results may be different from what is expected.
This is what happens with a source Image of 150, 96 and 72 Dpi in the same scenario:
Another important detail is the IDisposable nature of the Image object.
When you create one, you have to Dispose() of it; explicitly, calling the Dispose method, or implicitly, enclosing the Image contructor in a Using statement.
Also, possibly, don't assign an Image object directly loaded from a FileStream.
GDI+ will lock the file, and you will not be able to copy, move or delete it.
With the file, all resources tied to the Images will also be locked.
Make a copy with new Bitmap() (if you don't care of the above mentioned details), or with Image.Clone(), which will preserve the Image Dpi Resolution and PixelFormat.

I am not completely clear on what you are actually needing to do. But anyway, here is a WPF-friendly example of how to draw an image at a specific position inside another image.
Note if all you want to do is display the image in different size and/or put a black border around it, there are much simpler ways to do simply that, without having to create a second image, such as just laying out the image inside a panel that already has the border style you want.
Notice that I am using classes from the System.Windows.Media namespace because that is what WPF uses. These don't mix easily with the older classes from System.Drawing namespace (some of the class names conflict, and Microsoft's .Net framework lacks built-in methods for converting objects between those types), so normally one needs to simply decide whether to use one or the other sets of drawing tools. I assume you have been trying to use System.Drawing. Each has its own pros and cons that would take too long to explain here.
// using System.Windows.Media;
// using System.Windows.Media.Imaging;
private void DrawTwoImages()
{
// For InputPictureBox
var file = new Uri("C:\\image.png");
var inputImage = new BitmapImage(file);
// If your image is stored in a Resource Dictionary, instead use:
// var inputImage = (BitmapImage) Resources["image.png"];
InputPicture.Source = inputImage;
// imageCopy isn't actually needed for this example.
// But since you had it in yours, here is how it's done, anyway.
var imageCopy = inputImage.Clone();
// Parameters for setting up our output picture
int leftMargin = 50;
int topMargin = 5;
int rightMargin = 50;
int bottomMargin = 5;
int width = inputImage.PixelWidth + leftMargin + rightMargin;
int height = inputImage.PixelHeight + topMargin + bottomMargin;
var backgroundColor = Brushes.Black;
var borderColor = (Pen) null;
// Use a DrawingVisual and DrawingContext for drawing
DrawingVisual dv = new DrawingVisual();
using (DrawingContext dc = dv.RenderOpen())
{
// Draw the black background
dc.DrawRectangle(backgroundColor, borderColor, new Rect(0, 0, width, height));
// Copy input image onto output image at desired position
dc.DrawImage(inputImage, new Rect(leftMargin, topMargin,
inputImage.PixelWidth, inputImage.PixelHeight));
}
// For displaying output image
var rtb = new RenderTargetBitmap( width, height, 96, 96, PixelFormats.Pbgra32 );
rtb.Render(dv);
OutputPicture.Source = rtb;
}

C# drawing on picturebox, not persistent

I have a List<> object, "imagelist", that contains the paths of many images such as .png's. Now, with the following code:
private void paint_picture(PictureBox picture, string pathofpic)
{
Graphics g = picture.CreateGraphics();
Bitmap drawnpic = null;
if (imagelist.ContainsKey(picture.Name))
{
drawnpic = new Bitmap(pathofpic);
g.DrawImage(drawnpic, 0, 0, picture.Size.Width, picture.Size.Height);
imagelist[picture.Name] = pathofpic;
}
drawnpic.Dispose();
g.Dispose();
}
I call this every time the card's image is changed, but I can't seem to make the image persist on the picturebox, when I drag the picturebox across the form (for example, over other pictureboxes). The click and drag code is just moving the picturebox with the mouse, not really relevant.
I've tried invalidating the form when I de-select the image, but it doesn't do anything.
Is there something I'm missing? Screenshot below, I dragged one image around the form and it overwrote the other images it moved across:

That’s how painting works – you have to handle its Paint event and keep painting the same thing each time it needs repainting.
What you can do is draw on top of your original image:
Bitmap b = new Bitmap(picture.Image);
using (Graphics g = Graphics.FromImage(b)) {
using (Bitmap drawnpic = new Bitmap(pathofpic)) {
g.DrawImage(drawnpic, 0, 0, b.Width, b.Height);
}
}
picture.Image = b;
Then you’d save the original image somewhere and probably use it instead of picture.Image in the new Bitmap line.
And PascalCase for method names, please. ;)

How to generate a image with text and images in C#

I have several paragraphs of text and couple of pictures between these paragraphs.
Now, I want to generate a picture using these materials, merging them vertically. But all the blocks of the text and pictures can not have bigger width than that of the generating picture, which means I have to zoom out the origin pictures, and fill each paragraph of text into a rectangle to fit the width.
Here is the tough thing:
To figure out the size of the rectangle to contain the text, I need use Graphics.MeasureString() method, which needs an instance of Graphics used to generate my picture(now, I'm using a blank template picture). But I do not know the exact size of this Graphics until I figure out all the sizes of rectangles and pictures.
Is there any method to get an instance of Graphics without source image?
Or is there any other method to do this work?

hope this could help dude .
http://chiragrdarji.wordpress.com/2008/05/09/generate-image-from-text-using-c-or-convert-text-in-to-image-using-c/
https://web.archive.org/web/20131231000000/http://tech.pro/tutorial/654/csharp-snippet-tutorial-how-to-draw-text-on-an-image
http://www.codeproject.com/Questions/388845/HOW-TO-MAKE-HIGH-QAULITY-IMAGE-WITH-TEXT-IN-Csharp
thank you

For people how are intrested in a WPF solution (as asked):
public static BitmapSource CreateImage(string text, double width, double heigth)
{
// create WPF control
var size = new Size(width, heigth);
var stackPanel = new StackPanel();
var header = new TextBlock();
header.Text = "Header";
header.FontWeight = FontWeights.Bold;
var content = new TextBlock();
content.TextWrapping = TextWrapping.Wrap;
content.Text = text;
stackPanel.Children.Add(header);
stackPanel.Children.Add(content);
// process layouting
stackPanel.Measure(size);
stackPanel.Arrange(new Rect(size));
// Render control to an image
RenderTargetBitmap rtb = new RenderTargetBitmap((int)stackPanel.ActualWidth, (int)stackPanel.ActualHeight, 96, 96, PixelFormats.Pbgra32);
rtb.Render(stackPanel);
return rtb;
}

Don't scale image when creating new bitmap from existing image

Does anyone know how to create a new bitmap from an existing image with a taller height, but don't scale the image and just have transparent, black or white below the original image in the new bitmap?
I basically have one picture that is taller than the second and I need the second one to be as tall as the first, without stretching it.
img2 = new Bitmap(lImages[2],new Size(pictureBox.Image.Width,pictureBox.Image.Height));
img2 = ((Bitmap)img2).Clone(new Rectangle(0, 0, pictureBox.Image.Width, pictureBox.Image.Height), System.Drawing.Imaging.PixelFormat.Format24bppRgb);
C# .NET 4.0.

By using a Graphics object, you can achieve this easily:
Bitmap temp = new Bitmap(new Size(pictureBox.Image.Width,pictureBox.Image.Height));
using(Graphics g = Graphics.FromImage(temp))
{
g.DrawImage(img2, 0, 0);
}
img2 = temp;
Now img2 references a new Bitmap object of the required size which has the original (unstretched) image painted on it.
Note: To control the color of the extra space, add a call to g.FillRect before drawing the image.

Create your "standart" size bitmap and fill it with, let's say, white color and call Bitmap.MakeTransparent(Color.White) and draw your final image over it.

WinForm chart control: Change size of chart when saving it to a file

is there a way to change size of chart when using method Chart.SaveImage() from the source code?
Right now the only way I found to set the size of chart, is resize the form on which chart control (System.Windows.Forms.DataVisualization.Charting.Chart) sits. Can I explicit set its width and height? Trying to change Chart.Size, Chart.Width or Chart.Size doesn't work.

All right. The solution was so obvious that I couldn't found it thou 3 days - I had setted Chart.Dock = DockStyle.Fill, so changing Size property doesn't affect. After modified it to DockStyle.None I could change chart's size and (finally!) save it with appropriative width and height.

You can define it by redefining the Size property of the chart :
var ch = new Chart();
ch.Size = new Size(600, 250);

You'll probably have to save it to a memory stream, then use the Image class to change dimensions and then save it to file.
using(MemoryStream ms = new MemoryStream(4096))
{
myChart.SaveImage(ms,ImageFormat.Png);
using(Bitmap img = Image.FromStream(ms))
{
using(Graphics g = Graphics.FromImage(img))
g.DrawImage( b, 0, 0, newWidth, newHeight );
}
img.Save("where\to\save\chart.png",ImageFormat.Png);
}
}