I'm wondering if that's possible:
I got a c# application with something like a display consisting of about 11000 circles drawn on the Form.
What I want to achieve is to be able to draw text on that display, but not using the "real" pixels, but using the circles (rectangles) drawn on the form as pixels.
Edit 1:
When drawing text in c#, you would i.e. use something like Graphics.DrawString(...), giving the method a rectangle (so coordinates) in which the text should be drawn in. That text then is drawn in that rectangle using the screen pixels. What I want to do is draw text as well but not using the screen pixels but my custom pixels of which my display consists.
Edit 2
Method used to draw the circles on the Form; Circles is a list consisting of Circle objects, where circleRectangle returns the coordinates in which the circle should be drawn and Filled tells the method if the circle should be filled or not.
public void DrawCircles(Graphics g)
{
graphics = g;
graphics.SmoothingMode =System.Drawing.Drawing2D.SmoothingMode.AntiAlias;
Pen pen = new Pen(Color.Black, penthickness);
SolidBrush brush = new SolidBrush(Color.White);
for (int j = 0; j < Circles.Count;j++ )
{
graphics.DrawEllipse(pen, Circles[j].CircleRectangle);
if (Circles[j].Filled)
brush.Color = fillColor;
else
brush.Color = Color.White;
graphics.FillEllipse(brush, Circles[j].CircleRectangle);
}
}
Is this possible and if yes, how would I do that?
You could write on an invisible BitMap with the DrawText method and then scan the bitmap's pixels and turn the corresponding circles on.
Did that last week with the cells of DataGridView. Real easy.
Here is some code:
public void drawText(string text, Font drawFont)
{
Bitmap bmp = new Bitmap(canvasWidth, canvasHeight);
Graphics G = Graphics.FromImage(bmp);
SolidBrush brush = new SolidBrush(paintColor);
Point point = new Point( yourOriginX, yourOriginY );
G.DrawString(text, drawFont, brush, point);
for (int x = 0; x < canvasWidth; x++)
for (int y = 0; y < canvasHeight; y++)
{
Color pix = bmp.GetPixel(x, y);
setCell(x, y, pix); //< -- set your custom pixels here!
}
bmp.Dispose();
brush.Dispose();
G.Dispose();
}
Edit: You would use your dimensions and your origin for the DrawString, of course
Related
I'm trying to generate a custom Bitmap through code at a very small size and display it to a PictureBox, upscaled to fit said PictureBox. I am using the graphics object to do this in order to use NearestNeighbor interpolation to upscale single pixels perfectly.
I'm using the graphics object of a temporary default image that is in the PictureBoxs "Image" component on Form.Load, which is sized to be the perfect width and height to maintain the correct aspect ratio from the original Bitmap.
Here is the relevant code:
private void Form1_Load(object sender, EventArgs e)
{
bmp = new Bitmap(16, 9, PixelFormat.Format24bppRgb);
rnd = new Random();
GenerateImage();
}
private void GenerateImage()
{
for (int x = 0; x < bmp.Width; x++)
{
for (int y = 0; y < bmp.Height; y++)
{
int num = rnd.Next(2);
if (num == 0)
{
bmp.SetPixel(x, y, Color.White);
}
else
{
bmp.SetPixel(x, y, Color.Gold);
}
}
}
Bitmap image = new Bitmap(picOutput.Image);
grp = Graphics.FromImage(image);
grp.InterpolationMode = InterpolationMode.NearestNeighbor;
grp.DrawImage(
bmp,
new Rectangle(0, 0, image.Width, image.Height),
0,
0,
bmp.Width,
bmp.Height,
GraphicsUnit.Pixel
);
grp.Dispose();
picOutput.Image = image;
}
The problem is that the Bitmap seems to be drawn incorrectly. About half a pixel from the original Bitmap is cut off on the left and top edges of the Bitmap when displayed through the PictureBox, and that roughly half a pixel shows up as the original default image on the right and bottom edges. It's almost like the Bitmap was offset up and to the left while being drawn by the graphics object, it doesn't perfectly cover up the original default image like it was supposed to.
My first thought was the PictureBoxs SizeMode, which is still set to "Normal," but none of them change the problem at all. Here is a picture of the problem. The black edges on the right and bottom are part of the temporary default image (the image I used graphics from), which is completely black and covers the entire PictureBox area.
Can anyone offer some insight?
As user Jimi pointed out in a comment, grp.PixelOffsetMode = PixelOffsetMode.Half from this post solved the issue.
What is the proper wax to give a PNG image a colored background. as shown in the example below:
A PNG Image with different levels of opacity and transparent background:
A PNG image with a background color applied:
The question is to reproduce a new Image from the old one with a specified color.
The second part is how to add a color overlay to a PNG Image. perhaps replace the white with the new color.
This is the example PNG I have:
And this is the example PNG I want to get:
Correct me if I am wrong .. but this might be a possibility to use a grayscale image instead of a PNG with an alpha channel
Bitmap colorBitmap(Color forGroundColor, Color backGroundColor, Bitmap bmpGrayScale)
{
Size size = bmpGrayScale.Size;
Bitmap applyForgroundColor= new Bitmap(size.Width, size.Height);
Rectangle rect1 = new Rectangle(Point.Empty, bmpGrayScale.Size);
using (Graphics G1 = Graphics.FromImage(applyForgroundColor) )
{
G1.Clear(forGroundColor);
G1.DrawImageUnscaledAndClipped(applyForgroundColor, rect1);
}
for (int y = 0; y < size.Height; y++)
for (int x = 0; x < size.Width; x++)
{
Color c1 = applyForgroundColor.GetPixel(x, y);
Color c2 = bmpGrayScale.GetPixel(x, y);
applyForgroundColor.SetPixel(x, y, Color.FromArgb((int)(255 * c2.GetBrightness()), c1 ) );
}
Bitmap applyBackgroundColor= new Bitmap(size.Width, size.Height);
Rectangle rect2 = new Rectangle(Point.Empty, bmpGrayScale.Size);
using (Graphics G2 = Graphics.FromImage(applyBackgroundColor) )
{
G2.Clear(backGroundColor);
G2.DrawImageUnscaledAndClipped(applyForgroundColor, rect2);
}
return applyBackgroundColor;
}
I am trying to detect Circle inside Rectangle in AForge. I have successfully determined Rectangles but unable to find circles inside Rectangle. How to find shape inside another shape in AForge.
string strPath = Server.MapPath("~/Recipt001.png");
Bitmap myBitmap = new Bitmap(strPath);
//Some filters Grayscale, invert, threshold
//Blod Filtering
BlobCounter blobCounter = new BlobCounter();
blobCounter.ProcessImage(temp);
blobCounter.ObjectsOrder = ObjectsOrder.YX;
blobCounter.FilterBlobs = true;
Blob[] blobs = blobCounter.GetObjectsInformation();
Graphics g = Graphics.FromImage(myBitmap);
Pen redPen = new Pen(Color.Red, 2);
SimpleShapeChecker shapeChecker = new SimpleShapeChecker();
// dictionary of color to highlight different shapes
Dictionary<PolygonSubType, Color> colors = new Dictionary<PolygonSubType, Color>();
colors.Add(PolygonSubType.Unknown, Color.White);
colors.Add(PolygonSubType.Trapezoid, Color.Orange);
colors.Add(PolygonSubType.Parallelogram, Color.Red);
colors.Add(PolygonSubType.Rectangle, Color.Green);
colors.Add(PolygonSubType.Square, Color.Blue);
colors.Add(PolygonSubType.Rhombus, Color.Gray);
colors.Add(PolygonSubType.EquilateralTriangle, Color.Pink);
colors.Add(PolygonSubType.IsoscelesTriangle, Color.Purple);
colors.Add(PolygonSubType.RectangledTriangle, Color.SkyBlue);
colors.Add(PolygonSubType.RectangledIsoscelesTriangle, Color.SeaGreen);
for (int i = 0, n = blobs.Length; i < n; i++)
{
List<IntPoint> corners;
List<IntPoint> edgePoints = blobCounter.GetBlobsEdgePoints(blobs[i]);
Point center;
double radius;
if (shapeChecker.IsQuadrilateral(edgePoints, out corners))
{
if (shapeChecker.CheckPolygonSubType(corners) == PolygonSubType.Rectangle)
{
g.DrawPolygon(redPen, ToPointsArray(corners));
}
}
}
redPen.Dispose();
g.Dispose();
None of image processing libraries and even image processing in MATLAB lets you search ROI inside ROI (ROI - region of intrest like rectangles or circles). Concept is CROP REGION -> SEARCH OBJECTS IN REGION
So first locate primary rectangles, thereafter crop image to rectangles and perform circle search inside them. Otherwise search for all circles and all rectangles and then classify circles to be belonging to which rectangle using simple maths.
I try to draw a string (single character) in C# into a Bitmap at an exact position with:
Bitmap bmp = new Bitmap(64, 64);
Graphics g = Graphics.FromImage(bmp);
g.DrawString("W", font1, new SolidBrush(myColor), new Point(32,32);
There is so much empty space rendered around a single letter, that I can not guess the "needed" position to draw the character to have it at the correct position at the end.
By now I have the pixel exact dimension of the character (looking at bits in a separately rendered bitmap). But this information is useless, if I cannot draw the character at an exact position (e.g. center or top right corner or ....).
Are there other methods to draw text in C# on a bitmap? Or are there any converting methods to convert the real pixel position in something DrawString needs?
No need to look at the pixels or start working with your own font..
You can use a GraphicsPath instead of DrawString or TextRenderer, as it will let you know its net bounds rectangle with GraphicsPath.GetBounds() .
When you know it, you can calculate how to move the Graphics object using TranslateTransform:
private void button1_Click(object sender, EventArgs e)
{
string text = "Y"; // whatever
Bitmap bmp = new Bitmap(64, 64); // whatever
bmp.SetResolution(96, 96); // whatever
float fontSize = 32f; // whatever
using ( Graphics g = Graphics.FromImage(bmp))
using ( GraphicsPath GP = new GraphicsPath())
using ( FontFamily fontF = new FontFamily("Arial"))
{
testPattern(g, bmp.Size); // optional
GP.AddString(text, fontF, 0, fontSize, Point.Empty,
StringFormat.GenericTypographic);
// this is the net bounds without any whitespace:
Rectangle br = Rectangle.Round(GP.GetBounds());
g.DrawRectangle(Pens.Red,br); // just for testing
// now we center:
g.TranslateTransform( (bmp.Width - br.Width ) / 2 - br.X,
(bmp.Height - br.Height )/ 2 - br.Y);
// and fill
g.FillPath(Brushes.Black, GP);
g.ResetTransform();
}
// whatever you want to do..
pictureBox1.Image = bmp;
bmp.Save("D:\\__test.png", ImageFormat.Png);
}
A small test routine to let us see the centering better:
void testPattern(Graphics g, Size sz)
{
List<Brush> brushes = new List<Brush>()
{ Brushes.SlateBlue, Brushes.Yellow,
Brushes.DarkGoldenrod, Brushes.Lavender };
int bw2 = sz.Width / 2;
int bh2 = sz.Height / 2;
for (int i = bw2; i > 0; i--)
g.FillRectangle(brushes[i%4],bw2 - i, bh2 - i, i + i, i + i );
}
The GetBounds method returns a RectangleF; in my example it is {X=0.09375, Y=6.0625, Width=21, Height=22.90625}. Do note that due to rounding things can always be off by one..
You may or may not want to change the Graphics setting to special Smoothingmodes etc..
Also it should be noted that this will do automatic ie mechanical centering by the bounds rectangle. This may be quite different from 'optical or visual centering', which is rather hard to code and to some extent a matter of personal taste. But typography is as much an art as a profession..
For example, I have pic 1 and pic 2, they are same dimensions except pic 2 has a square in the top left corner. How can I compare the two pictures get the location of each pixel thats colour has changed and then draw to each pixel? Thanks.
I've been playing with images recently, and this is what I've been doing:
using System.Drawing;
using System.Drawing.Imaging;
// Open your two pictures as Bitmaps
Bitmap im1 = (Bitmap)Bitmap.FromFile("file1.bmp");
Bitmap im2 = (Bitmap)Bitmap.FromFile("file2.bmp");
// Assuming they're the same size, loop through all the pixels
for (int y = 0; y < im1.Height; y++)
{
for (int x = 0; x < im1.Width; x++)
{
// Get the color of the current pixel in each bitmap
Color color1 = im1.GetPixel(x, y);
Color color2 = im2.GetPixel(x, y);
// Check if they're the same
if (color1 != color2)
{
// If not, generate a color...
Color myRed = Color.FromArgb(255, 0, 0);
// .. and set the pixel in one of the bitmaps
im1.SetPixel(x, y, myRed);
}
}
}
// Save the updated bitmap to a new file
im1.Save("newfile.bmp", ImageFormat.Bmp);
This might not be exactly what you want to do, but hopefully should give you some ideas on how to get started.