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C# form size does not match

I have a c# form that I setup with
int INTERFACE_right = 20;
int INTERFACE_down = 25;
int INTERFACE_width = 846;
int INTERFACE_height = 60;
this.Left = INTERFACE_right;
this.Top = INTERFACE_down;
this.Size = new Size(INTERFACE_width, INTERFACE_height);
And I copy a part of the screen with (I hide the form before with the opacity) with the exact same parameter. So the form should be exactly on top of the part of the screen I copy:
Bitmap grabOnScreen(){
Rectangle rect = new Rectangle(INTERFACE_right, INTERFACE_down, INTERFACE_width, INTERFACE_height);
Bitmap bmp = new Bitmap(rect.Width, rect.Height, PixelFormat.Format32bppArgb);
Graphics g = Graphics.FromImage(bmp);
g.CopyFromScreen(rect.Left, rect.Top, 0, 0, bmp.Size, CopyPixelOperation.SourceCopy);
//bmp.Save("test.jpg", ImageFormat.Jpeg);
return bmp;
}
As I save the image to test.jpg, I know I grab the good part of the screen with the right dimensions etc.
The form should have the same size, and the same location than where I grab the picture, but in pratice the form is bigger than the picture, but as the good location.
How can I match the form size to the same than the rect where i grab the picture ?

Get bitmap and draw it into image

I am trying to save my drawing from picturebox into bitmap and draw that bitmap into image. So far, nothing has appeared in the final image, but while debugging I can only say, that the original bitmap is not null and with/height are correct. However nothing appears after I draw it into image.
I save my drawing into bitmap like this:
GraphicsPath path = RoundedRectangle.Create(x, y, width, height, corners, RoundedRectangle.RectangleCorners.All);
g.FillPath(Brushes.LightGray, path);
g.SetClip(path);
using (Font f = new Font("Tahoma", 9, FontStyle.Bold))
g.DrawString(mtb_hotspotData.Text, f, Brushes.Black, textX, textY);
g.ResetClip();
bitmap = new Bitmap(width, height, g);
Then save it:
hs.bitmap = new Bitmap(bitmap);
And finally use it:
for (int i = 0; i < imageSequence.Count; i++) {
Graphics g = Graphics.FromImage(imageSequence[i]);
//g.CompositingMode = CompositingMode.SourceOver;
//hotspot.bitmap.MakeTransparent();
int x = hotspot.coordinates[i].X;
int y = hotspot.coordinates[i].Y;
g.DrawImage(hotspot.bitmap, new Point(x, y));
}
return imageSequence;
So far I was not able to find any problem in this solution, therefore I have no idea, where the malfunction is.

You seem to misunderstand the relation of a Bitmap and a Graphics object.
A Graphics object does not contain any graphics; it is a tool used to draw into a bitmap of some sort.
The Bitmap constructor you are using (public Bitmap(int width, int height, Graphics g)) does not really connect the Bitmap and the Graphics object. It only uses the dpi resolution from the Graphics.
You don't show how your Graphics is created. If you want to draw into a Bitmap (as opposed to a control's surface) the most direct way is this:
Bitmap bitmap = new Bitmap(width, height);
bitmap.SetResolution(dpiX, dpiY); // optional
using (Graphics G = Graphics.FromImage(bitmap ))
{
// do the drawing..
// insert all your drawing code here!
}
// now the Bitmap can be saved or cloned..
bitmap.Save(..);
hs.bitmap = new Bitmap(bitmap); // one way..
hs.bitmap = bitmap.Clone(); // ..or the other
// and finally disposed of (!!)
bitmap.Dispose();

how to draw a part of a png image c#

I'm trying to draw a part of a .png image but the code i found is not working. this is my code
//define canvas
canvas = pb.CreateGraphics();
sPicture = new Bitmap(pb.Width, pb.Height);
sCanvas = Graphics.FromImage(sPicture);
// Create a Bitmap object from a file.
Image image = Image.FromFile(#"");
// Clone a portion of the Bitmap object.
Rectangle cloneRect = new Rectangle(0, 0, 11, 6);
System.Drawing.Imaging.PixelFormat format =
image.PixelFormat;
Image cloneBitmap = image.Clone(cloneRect, format); //Error: No overload for method 'Clone' takes2 arguments
// Draw the cloned portion of the Bitmap object.
canvas.DrawImage(cloneBitmap, 0, 0);
This is for a sprite sheet and thanks.

You don't need to use Clone(), you can do this directly with Graphics.DrawImage(). It looks like you are trying to do this in WinForms. If, so handle OnPaint for the control you want to draw on. In the example below I'm drawing directly on the form.
private void Form1_Paint(object sender, PaintEventArgs e)
{
Graphics graphics = e.Graphics;
int width = 60;
int height = 60;
// Create a Bitmap object from a file.
Image sourceImage = Image.FromFile(#"C:\Users\Mike\Downloads\logo.png");
// Draw a portion of the source image.
Rectangle sourceRect = new Rectangle(0, 0, width, height);
graphics.DrawImage(sourceImage, 0, 0, sourceRect, GraphicsUnit.Pixel);
}
If you want to do this without WinForms, there is the extra step of creating the target Graphics instance.
int width = 60;
int height = 60;
// Create a Bitmap object from a file.
Image sourceImage = Image.FromFile(#"C:\Users\Mike\Downloads\logo.png");
// Create a drawing target
Bitmap bitmap = new Bitmap(width, height, sourceImage.PixelFormat);
Graphics graphics = Graphics.FromImage(bitmap);
// Draw a portion of the source image.
Rectangle sourceRect = new Rectangle(0, 0, width, height);
graphics.DrawImage(sourceImage, 0, 0, sourceRect, GraphicsUnit.Pixel);
// Save
bitmap.Save(#"C:\Users\Mike\Downloads\out.png");

Issues with DrawString on a Bitmap

I have this constructor that takes in an input of an array of Color objects and some misc strings (like file location and size of list), and stores this heatmap into a bitmap instance called _image_. Everything works out fine, but my main issue is I have no way to render text onto this heatmap. I would like to overlay title text and x and y-axis labels onto this bitmap.
public HeatMap(IEnumerable<Color> colors, int width, int height, string file, int U, int V) {
if (colors == null)
throw new ArgumentNullException("colors");
if (width <= 0)
throw new ArgumentException("width must be at least 1");
if (height <= 0)
throw new ArgumentException("height must be at least 1");
_width = width;
_height = height;
_file = file;
_image = new Bitmap(U, V, PixelFormat.Format32bppArgb);
Graphics graphics = Graphics.FromImage(_image);
graphics.Clear(Color.White);
graphics.Dispose();
int x = 0;
int y = 0;
foreach (Color color in colors) {
_image.SetPixel(x, y, color); // This can be speeded up by using GH_MemoryBitmap if you want.
y++;
if (y >= V) {
y = 0;
x++;
}
if (x >= U)
break;
}
}
Below, I also have a method that resizes the image (without too much distortion), and I figured I might as well make use of this since I have a graphics object I can use, like so:
private Bitmap ResizeBitmap(Bitmap sourceBMP, int width, int height) {
Bitmap result = new Bitmap(width, height);
using (Graphics g = Graphics.FromImage(result)) {
g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.NearestNeighbor;
g.DrawImage(sourceBMP, 0, 0, width, height);
g.DrawString("A heatmap.", SystemFonts.DefaultFont, Brushes.Black, 10, 10);
}
return result;
}
Using the above, I was able to overlay text over it, as a starting point. My question is, how do I add a white boarder over the above image (so my text doesn't overlap my graph), and then overlay x and y-axis text onto it?
I guess my specific question really is - how do I render text onto, say, every four columns of my heatmap? In most instances, there are 100 x-axis objects, and like 24 y-axis objects. The y-axis would have the time of the day, while the x-axis has the day of the year. My familiarity with using graphics in C# is very low, so any pointers is very appreciated.

You've to use the DrawString before the graphics.Dispose() and after the Clear().
Graphics graphics = Graphics.FromImage(_image);
graphics.Clear(Color.WhiteSmoke);
graphics.DrawString("your text", SystemFonts.DefaultFont, Brushes.Black, new PointF(0, 0));
graphics.Dispose();
Where the PointF(0, 0) represents the up-left corner of your text placeholder, you've to calculate the text position based on the positions of your heatmap.
UPDATE (alignment)
You can align your text in relation with a virtual rectangle, doing something like:
Graphics graphics = Graphics.FromImage(_image);
graphics.Clear(Color.WhiteSmoke);
StringFormat stringFormat = new StringFormat() { Alignment = StringAlignment.Center, LineAlignment = StringAlignment.Center };
graphics.DrawString("your text", SystemFonts.DefaultFont, Brushes.Black, new RectangleF(0, 0, 100, 100), stringFormat);
graphics.Dispose();
In this case I've created a virtual box of 100x100 positioned on the top-left corner, and the text is h/v centered relatively to this box.

Merging 2 images using C#

I want to merge two pictures in my C# program.
the first one is any picture in grayscale mode, and the second one is like in this picture:
Both of the pictures/images have the same size, and this is my code:
Bitmap first = new Bitmap (picturebox1.image);
Bitmap second = new Bitmap (picturebox2.image);
Bitmap result = new Bitmap (first.width, first.height);
Graphics g = Graphics.FromImage(result);
g.DrawImageUnscaled(first, 0, 0);
g.Flush();
g.DrawImageUnscaled(second, 0, 0);
g.Flush();
picturebox3.image = result;
I can join those picture, but the result has smaller size than the two originals (both pictures have same size). Could anyone give me some suggestions?
Additionally, I want the result picture has condition like this :
if the edge pixel in 2nd picture dropped to the bright side at the 1st one, it will be dark, otherwise when the edge dropped to the dark side, it will be bright (seem glow).
so the text will be semi transparent.
Here's an example of the results I want.
Could anyone give some suggestions please?

It was for joining
Bitmap first = new Bitmap (picturebox1.Image);
Bitmap second = new Bitmap (picturebox2.Image);
Bitmap result = new Bitmap (first.Width+first.Width, first.Height);
Graphics g = Graphics.FromImage(result);
g.DrawImageUnscaled(first, 0, 0);
g.DrawImageUnscaled(second,first.Width, 0);
Try this for merging one on top another . set alpha by yourself ( red: U can use BitMap.MakeTransParent if u not want alpha)
public Bitmap SetImageOpacity(Image image, float opacity)
{
try
{
//create a Bitmap the size of the image provided
Bitmap bmp = new Bitmap(image.Width, image.Height);
//create a graphics object from the image
using (Graphics gfx = Graphics.FromImage(bmp))
{
//create a color matrix object
ColorMatrix matrix = new ColorMatrix();
//set the opacity
matrix.Matrix33 = opacity;
//create image attributes
ImageAttributes attributes = new ImageAttributes();
//set the color(opacity) of the image
attributes.SetColorMatrix(matrix, ColorMatrixFlag.Default, ColorAdjustType.Bitmap);
//now draw the image
gfx.DrawImage(image, new Rectangle(0, 0, bmp.Width, bmp.Height), 0, 0, image.Width, image.Height, GraphicsUnit.Pixel, attributes);
}
return bmp;
}
catch (Exception ex)
{
return null;
}
}
private void button1_Click(object sender, EventArgs e)
{
Bitmap first = new Bitmap(pictureBox1.Image);
Bitmap second = SetImageOpacity(pictureBox2.Image, 0.5f);
//Bitmap result = new Bitmap(first.Width, first.Height);
//fix :
Bitmap result = new Bitmap(Math.Max(first.Width,second.Width), Math.Max(first.Height,second.Height));
Console.WriteLine(first.Width);
Graphics g = Graphics.FromImage(result);
g.DrawImageUnscaled(first, 0, 0);
g.DrawImageUnscaled(second, 0, 0);
pictureBox3.Image = result;
result.Save("result.jpg" );
}
}
}
And Coming For watermark why not you want to use Drawstring with alpha
here is article for all these http://www.codeproject.com/Articles/5034/How-to-implement-Alpha-blending

You need to include the System.Drawing.Imaging namespace to make this code work.
Go through following code:
private void CombineImages(FileInfo[] files)
{
//change the location to store the final image.
string finalImage = #"C:\\MyImages\\FinalImage.jpg";
List imageHeights = new List();
int nIndex = 0;
int width = 0;
foreach (FileInfo file in files)
{
Image img = Image.FromFile(file.FullName);
imageHeights.Add(img.Height);
width += img.Width;
img.Dispose();
}
imageHeights.Sort();
int height = imageHeights[imageHeights.Count - 1];
Bitmap img3 = new Bitmap(width, height);
Graphics g = Graphics.FromImage(img3);
g.Clear(SystemColors.AppWorkspace);
foreach (FileInfo file in files)
{
Image img = Image.FromFile(file.FullName);
if (nIndex == 0)
{
g.DrawImage(img, new Point(0, 0));
nIndex++;
width = img.Width;
}
else
{
g.DrawImage(img, new Point(width, 0));
width += img.Width;
}
img.Dispose();
}
g.Dispose();
img3.Save(finalImage, System.Drawing.Imaging.ImageFormat.Jpeg);
img3.Dispose();
imageLocation.Image = Image.FromFile(finalImage);
}
Follow Link:
http://www.niteshluharuka.com/2012/08/combine-several-images-to-form-a-single-image-using-c/

This codeproject article shows how to watermark an image with text as well as another image.
In summary, what you have to do is draw your watermark image over the image with the desired transparency.