Fill / append rectangle on bottom of image c# - c#

I need to fill an rectangle on bottom of my image, but not over the image, so it should be a kind of append a rectangle to bottom of image.
What I have for now:
private void DrawRectangle()
{
string imageFilePath = #"c:\Test.jpg";
Bitmap bitmap = (Bitmap)Image.FromFile(imageFilePath);
using (Graphics graphics = Graphics.FromImage(bitmap))
{
using (Image img = Image.FromFile(imageFilePath))
{
SolidBrush brush = new SolidBrush(Color.Black);
int width = img.Width;
int height = img.Height - 350;
graphics.FillRectangle(brush, 0, height, width, 350);
}
}
bitmap.Save(#"c:\Test1.jpg");
}
But this is over the image.
Any idea's?
Thank you.

You need to know the dimensions of your original image in order to set the size of the new bitmap, which must be larger to accommodate the rectangle.
private void DrawRectangle()
{
string imageFilePath = #"c:\Test.jpg";
int rectHeight = 100;
using (Image img = Image.FromFile(imageFilePath)) // load original image
using (Bitmap bitmap = new Bitmap(img.Width, img.Height + rectHeight)) // create blank bitmap of desired size
using (Graphics graphics = Graphics.FromImage(bitmap))
{
// draw existing image onto new blank bitmap
graphics.DrawImage(img, 0, 0, img.Width, img.Height);
SolidBrush brush = new SolidBrush(Color.Black);
// draw your rectangle below the original image
graphics.FillRectangle(brush, 0, img.Height, img.Width, rectHeight);
bitmap.Save(#"c:\Test1.bmp");
}
}

take a look at the FillRectangle() method overloads.. it has one with the following definition: FillRectangle(Brush brush, int PositionX, int PositionY, int Width, int Height)
your problem most likely stems on using an improper overload for what you're doing.

Related

how to have my rectangle always on the middle of the image without knowing the size of the incomming image

Trying to add a watermark image to a png image, i´ve been able to do it, but i want to take out the hardCoded size regulation for the rectangle of the waterMark, and make it always stay in the center of the image. How can i achieve this.
public Form1()
{
InitializeComponent();
picBox.Parent = this;
picBox.Dock = DockStyle.Fill;
picBox.SizeMode = PictureBoxSizeMode.Zoom;
Bitmap Jpg = new Bitmap(#"C:\Users\tferreira\Desktop\213123.PNG");
using (Bitmap Bmp = new Bitmap(#"C:\Users\tferreira\Desktop\logo.png"))
{
using (Bitmap WatermarkBmp = new Bitmap(Bmp, Bmp.Width / 1, Bmp.Height / 1))
{
picBox.Image = WatermarkImage(Jpg, WatermarkBmp, new Point(400, 100), 0.40F);
}
}
}
public Bitmap WatermarkImage(Bitmap ImageToWatermark, Bitmap Watermark, Point WatermarkPosition, float Opacity)
{
using (Graphics G = Graphics.FromImage(ImageToWatermark))
{
using (ImageAttributes IA = new ImageAttributes())
{
ColorMatrix CM = new ColorMatrix();
CM.Matrix33 = Opacity;
IA.SetColorMatrix(CM);
G.DrawImage(Watermark, new Rectangle(WatermarkPosition, Watermark.Size), 0, 0, Watermark.Width, Watermark.Height, GraphicsUnit.Pixel, IA);
}
}
return ImageToWatermark;
}
Right now the images are hardCoded but that will be taken out. If anyone can help me make this watermark allways stay centered i thank you.
I fixed this problem with this nice peace of code.
System.Drawing.Image img = System.Drawing.Image.FromFile(JpgFilePath);
Bitmap jpg = new Bitmap(img);
filePath = JpgFilePath;
int Width = jpg.Width;
int Height = jpg.Height;
jpg.SetResolution(300, 300);
WaterMarked = WatermarkImage(jpg, WaterMarkBit, new Point((Width - WaterMarkBit.Width) / 2, (Height - WaterMarkBit.Height) / 2), 0.4F);
WaterMarked.Save(filePath.Replace(".jpg", "") + ".tif", ImageFormat.Tiff);
filesJpgForTif.Add(JpgFilePath.Replace("jpg", "tif"));
Using the the sizes of the image and sizes of the watermark and divide it by 2 it makes the image always stay centered.

Watermark not drawing in image

I had an error come up:
A Graphics Object cannot be Created from an Image that has an Indexed Pixel Format
So I implemented this code into my method: Solution for "A Graphics Object cannot be Created from an Image that has an Indexed Pixel Format"
But now my watermark doesnt want to draw on my image.
Please can anyone assist.
Code:
private Image AddWaterMark(Image original)
{
Image waterMark = Image.FromFile(ConfigurationManager.AppSettings["GalleryFolder"] + #"\watermark.png");
Bitmap bm = (Bitmap)original;
Size waterMarkResize = ResizeFit(new Size(original.Width, original.Height));
using (Image watermarkImage = new Bitmap(waterMark, waterMarkResize))
using (Graphics imageGraphics = Graphics.FromImage(new Bitmap(bm.Width, bm.Height)))
{
imageGraphics.DrawImage(bm, new Rectangle(0, 0, bm.Width, bm.Height), 0, 0, bm.Width, bm.Height, GraphicsUnit.Pixel);
using (TextureBrush watermarkBrush = new TextureBrush(watermarkImage))
{
int x = (original.Width / 2 - watermarkImage.Width / 2);
int y = (original.Height / 2 - watermarkImage.Height / 2);
watermarkBrush.TranslateTransform(x, y);
imageGraphics.FillRectangle(watermarkBrush, new Rectangle(new Point(x, y), new Size(watermarkImage.Width + 1, watermarkImage.Height)));
}
}
return bm;
}
You're creating a new Bitmap to pass to Graphics.FromImage then returning the uneditted original Bitmap. Create the new Bitmap independently, pass it to FromImage then return the new Bitmap.
var edit = new Bitmap(bm.Width, bm.Height);
// ...
using (Graphics imagesGraphics = Graphics.FromImage(edit))
{
// draw original
// draw watermark
}
return edit;

Generated Bitmap Displays Weirdly in PictureBox

I cannot seem to programmatically create a colored bitmap to display in a PictureBox. The bitmap saves normally as a file, but is faded at the edges when displayed in a PictureBox. Here is simplified code used to create and display the Bitmap (in actual code, the bitmap generation is completely separate from the form, so forcing the bitmap size to match the picturebox size isn't possible):
Bitmap Bmp = new Bitmap(4, 4, System.Drawing.Imaging.PixelFormat.Format24bppRgb);
using (Graphics gfx = Graphics.FromImage(Bmp))
using (SolidBrush brush = new SolidBrush(Color.BlueViolet))
{
gfx.FillRectangle(brush, 0, 0, 4, 4);
}
Then set the Image value on a PictureBox to the generated Bitmap:
pictureBox1.Image = Bmp;
Here is the resulting bitmap displayed in a 300x300 picturebox:
How do I set the Image on the PictureBox so that it displays the colored bitmap properly (full solid)?
EDIT: I am restricted to generating smaller source bitmaps, so upscaling into a PictureBox is unavoidable. The problem appears when the generated source bitmap is 4px or 100px square, so I believe these are relevant cases.
EDIT: The PictureBox scaling should be set to stretch or zoom for the issue to manifest. In this example case the 4x4 source bitmap is stretched to 300x300.
EDIT: The basic problem is PictureBox's inability to upscale small bitmaps into large controls. This is confusing because the Bitmap upscales nicely into a PictureBox.Background image. Unless you have a magic bullet that will fix the image upscaling problem, I think it might be best to go for clear and simple workarounds in your answer.
You are generating a 4x4 bitmap and it's being stretched. Specify the size to match the picture box instead:
int width = pictureBox1.Width;
int height = pictureBox1.Height;
var Bmp = new Bitmap(width, height, System.Drawing.Imaging.PixelFormat.Format24bppRgb);
using (Graphics gfx = Graphics.FromImage(Bmp))
using (var brush = new SolidBrush(Color.BlueViolet))
{
gfx.FillRectangle(brush, 0, 0, width, height);
}
pictureBox1.Image = Bmp;
You will need to turn anti-aliasing off. Also, since you are using one color for the whole picturebox, why not make the bitmap 1x1? If you need it 4x4, change the int the top of the example from 1 to 4.
int hw = 1;
Bitmap Bmp = new Bitmap(hw, hw,
System.Drawing.Imaging.PixelFormat.Format24bppRgb);
using (Graphics gfx = Graphics.FromImage(Bmp))
{
// Turn off anti-aliasing and draw an exact copy
gfx.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.None;
gfx.CompositingMode = System.Drawing.Drawing2D.CompositingMode.SourceCopy;
using (SolidBrush brush = new SolidBrush(Color.BlueViolet))
{
gfx.FillRectangle(brush, 0, 0, hw, hw);
}
}
pictureBox1.Image = Bmp;
UPDATE
Since you are still having the same issue by setting the picturebox to the image, you will have to get the graphics object from the picturebox and draw directly on it.
The code is very similar.
using (Graphics gfx = Graphics.FromImage(pictureBox1.Image))
{
// Turn off anti-aliasing and draw an exact copy
gfx.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.None;
gfx.CompositingMode = System.Drawing.Drawing2D.CompositingMode.SourceCopy;
using (SolidBrush brush = new SolidBrush(Color.BlueViolet))
{
gfx.FillRectangle(brush, 0, 0,
pictureBox11.Width - 1,
pictureBox11.Height - 1);
}
}
// Force the picturebox to redraw with the new image.
// You could also use pictureBox11.Refresh() to do the redraw.
pictureBox11.Invalidate();
I tried to test your code and the image were properly displayed.
But when i used this code:
Rectangle srcRect = New Rectangle(0, 0, Bmp.Width, Bmp.Height);
Rectangle dstRect = New Rectangle(0, 0, PictureBox1.Width, PictureBox1.Height);
g = PictureBox1.CreateGraphics;
g.DrawImage(Bmp, dstRect, srcRect, GraphicsUnit.Pixel);
g.Dispose();
I did get exactly your result. In order to fix it:
Rectangle srcRect = New Rectangle(0, 0, Bmp.Width - 1, Bmp.Height - 1);
Rectangle dstRect = New Rectangle(0, 0, PictureBox1.Width, PictureBox1.Height);
g = PictureBox1.CreateGraphics;
g.DrawImage(Bmp, dstRect, srcRect, GraphicsUnit.Pixel);
g.Dispose();
Edit:
So you have the bitmap and you want to stretch it. And the bitmap has ane solid color. Do this insted:
Color pixelColor = Bmp.GetPixel(0, 0);
PictureBox1.BackColor = pixelColor;
valter

Crop a bitmap and expand the size if necessary

I want to crop a bitmap with this function but the bitmap could be smaller then the crop area so I want to get the bitmap bigger in that case.
As example I have a bitmap which is 200x250 and if I use the CropBitmap method with 250x250 I get an out of memory error. It should return a bitmap with 250x250 where the missing left 50px are filled with white.
How can I achieve that?
public Bitmap CropBitmap(Bitmap bitmap, int cropX, int cropY, int cropWidth, int cropHeight)
{
var rect = new Rectangle(cropX, cropY, cropWidth, cropHeight);
if(bitmap.Width < cropWidth || bitmap.Height < cropHeight)
{
// what now?
}
return bitmap.Clone(rect, bitmap.PixelFormat);
}
Create a new Bitmap with the appropriate size. Then get a System.Drawing.Graphics and use it to create the white area and to insert the source image. Something like this:
if (bitmap.Width < cropWidth && bitmap.Height < cropHeight)
{
Bitmap newImage = new Bitmap(cropWidth, cropHeight, bitmap.PixelFormat);
using (Graphics g = Graphics.FromImage(newImage))
{
// fill target image with white color
g.FillRectangle(Brushes.White, 0, 0, cropWidth, cropHeight);
// place source image inside the target image
var dstX = cropWidth - bitmap.Width;
var dstY = cropHeight - bitmap.Height;
g.DrawImage(bitmap, dstX, dstY);
}
return newImage;
}
Note, that I replaced the || in the outer if expression with &&. To make it work with ||, you have to calculate the source region and use another overload of Graphics.DrawImage

C# Drawstring clear rectangle Or no rectangle? possible

here is the code i'm using, i really need to make it so the text does not appear inside of a box. is that possible?
int width = (int)g.MeasureString(line, f).Width;
int height = (int)g.MeasureString(line,f).Height;
b = new Bitmap(b, new Size(width, height));
g = Graphics.FromImage(b);
g.Clear(Color.Empty);
g.DrawString(line,f, new SolidBrush(Color.Black), 0, 0);
b.Save(savepoint+line+".tif", System.Drawing.Imaging.ImageFormat.Tiff);
g.Flush();
What i mean is there can be no Rectangle around the text that is converted to image. So I need to watch it to the same color to create the illusion there is no box, or to never write out that rectangle period.
Use the color Transparent for the backgtround and a file format that supports transparency, like PNG:
var measure = g.MeasureString(line, f);
int width = (int)measure.Width;
int height = (int)measure.Height;
using (Bitmap b = new Bitmap(width, height)) {
using (Graphics bg = Graphics.FromImage(b)) {
bg.Clear(Color.Transparent);
using (Brush black = new SolidBrush(Color.Black)) {
bg.DrawString(line, f, black, 0, 0);
}
}
b.Save(savepoint+line+".png", System.Drawing.Imaging.ImageFormat.Png);
}
I notice that you did overwrite your Graphics instance, didn't dispose the objects that you create, and called Graphics.Flush for no apparent reason...

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