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Freehand image cropping with mouse and get all points in c# [duplicate]

I made a program that lets you do a random selection then the selected area to save into a new image, but I got a problem it doesn't work how it's supposed to... I will post my code here so you can have a look:
private List<Point> Points = null;
private bool Selecting = false;
private Bitmap SelectedArea = null;
private void pictureBox5_MouseDown(object sender, MouseEventArgs e)
{
Points = new List<Point>();
Selecting = true;
}
private void pictureBox5_MouseMove(object sender, MouseEventArgs e)
{
if (!Selecting) return;
Points.Add(new Point(e.X, e.Y));
pictureBox5.Invalidate();
}
private void pictureBox5_MouseUp(object sender, MouseEventArgs e)
{
Selecting = false;
// Copy the selected area.
SelectedArea = GetSelectedArea(pictureBox5.Image, Color.Transparent, Points);
SelectedArea.Save(#"C:\Users\User\Desktop\Gallery\image" + NumberOfClick.ToString() + "cropped.jpeg", ImageFormat.Jpeg);
string filename = #"C:\Users\User\Desktop\Gallery\image" + NumberOfClick.ToString() + "cropped.jpeg";
if(File.Exists(filename))
{
button1.Visible = true;
pictureBox5.Visible = false;
}
}
private void pictureBox5_Paint(object sender, PaintEventArgs e)
{
if ((Points != null) && (Points.Count > 1))
{
using (Pen dashed_pen = new Pen(Color.Black))
{
dashed_pen.DashPattern = new float[] { 5, 5 };
e.Graphics.DrawLines(Pens.White, Points.ToArray());
e.Graphics.DrawLines(dashed_pen, Points.ToArray());
}
}
}
private Bitmap GetSelectedArea(Image source, Color bg_color, List<Point> points)
{
// Make a new bitmap that has the background
// color except in the selected area.
Bitmap big_bm = new Bitmap(source);
using (Graphics gr = Graphics.FromImage(big_bm))
{
// Set the background color.
gr.Clear(bg_color);
// Make a brush out of the original image.
using (Brush br = new TextureBrush(source))
{
// Fill the selected area with the brush.
gr.FillPolygon(br, points.ToArray());
// Find the bounds of the selected area.
Rectangle source_rect = GetPointListBounds(points);
// Make a bitmap that only holds the selected area.
Bitmap result = new Bitmap(
source_rect.Width, source_rect.Height);
// Copy the selected area to the result bitmap.
using (Graphics result_gr = Graphics.FromImage(result))
{
Rectangle dest_rect = new Rectangle(0, 0,
source_rect.Width, source_rect.Height);
result_gr.DrawImage(big_bm, dest_rect,
source_rect, GraphicsUnit.Pixel);
}
// Return the result.
return result;
}
}
}
private Rectangle GetPointListBounds(List<Point> points)
{
int xmin = points[0].X;
int xmax = xmin;
int ymin = points[0].Y;
int ymax = ymin;
for (int i = 1; i < points.Count; i++)
{
if (xmin > points[i].X) xmin = points[i].X;
if (xmax < points[i].X) xmax = points[i].X;
if (ymin > points[i].Y) ymin = points[i].Y;
if (ymax < points[i].Y) ymax = points[i].Y;
}
return new Rectangle(xmin, ymin, xmax - xmin, ymax - ymin);
}
This is how I am doing and saving the cropped images.
And also this is how I am uploading the pictures:
OpenFileDialog f = new OpenFileDialog();
f.Filter = "Image files (*.jpg, *.jpeg, *.jpe, *.jfif, *.png) | *.jpg; *.jpeg; *.jpe; *.jfif; *.png";
if (f.ShowDialog() == DialogResult.OK)
{
currentImage = Image.FromFile(f.FileName);
pictureBox1.Image = currentImage;
}
pictureBox1.Image.Save(#"C:\Users\User\Desktop\Gallery\image1.jpeg", ImageFormat.Jpeg);
DialogResult result = MessageBox.Show("Crop your image", "Information", MessageBoxButtons.OK);
if(result == DialogResult.OK)
{
pictureBox5.Visible = true;
button1.Visible = false;
pictureBox5.Image = pictureBox1.Image;
}
In pictureBox5 I am selecting and cropping the picture.
mySelection
croppedImage

You need to calculate the zoom and the offset of the image when it is zoomed.
Here is how to do that; this assumes the PictureBox is indeed in Zoom mode, not in Stretch mode. If you stretch it you need to calculate the zooms for x and y separately..
SizeF sp = pictureBox5.ClientSize;
SizeF si = pictureBox5.Image.Size;
float rp = sp.Width / sp.Height; // calculate the ratios of
float ri = si.Width / si.Height; // pbox and image
float zoom = (rp > ri) ? sp.Height / si.Height : sp.Width / si.Width;
float offx = (rp > ri) ? (sp.Width - si.Width * zoom) / 2 : 0;
float offy = (rp <= ri)? (sp.Height - si.Height * zoom) / 2 : 0;
Point offset = Point.Round(new PointF(offx, offy));
You calculate this after setting the Image and after resizing the PictureBox..
Now you can transform each drawn point into a zoomed or an unzoomed coordinate:
PointF zoomed(Point p1, float zoom, Point offset)
{
return (new PointF(p1.X * zoom + offset.X, p1.Y * zoom + offset.Y));
}
PointF unZoomed(Point p1, float zoom, Point offset)
{
return (new PointF((p1.X - offset.X) / zoom, (p1.Y - offset.Y) / zoom));
}
Here is a demo the draws on to either a normal (left) or a zoomed in (middle) image. To the right is the result of placing your GetSelectedArea bitmap onto a PictureBox with a checkerbox background:
Case 1: If you store the points as they come in: In your GetSelectedArea method use this point list instead:
private Bitmap GetSelectedArea(Image source, Color bg_color, List<Point> points)
{
var unzoomedPoints =
points.Select(x => Point.Round((unZoomed(Point.Round(x), zoom, offset))))
.ToList();
// Make a new bitmap that has the background
After this replace each reference to points in the method by one to unzoomedPoints. Actually there are just two of them..
Case 2: If you store the points already 'unZoomed' :
Points.Add(unZoomed(e.Location, zoom, offset));
you can use the list directly..

How to correctly control translation transformation position after doubleAnimation completes in c#

I have an ellipse in the middle of a Canvas using this code:
var FixedCircle = new Ellipse
{
Width = 25,
Height = 25,
Stroke = color,
Fill = color,
StrokeThickness = 3
};
var centerX = ActualWidth / 2;
var centerY = ActualHeight / 2;
FixedCircle.Margin = new Thickness(centerX, centerY, 1, 1);
Children.Add(FixedCircle);
InvalidateVisual();
I want to animate the ellipse, making it go from left and back to center (starting middle point).
I am setting coordinates (centerX,centerY) and (0,centerY) as starting and end points, also I am using the lines
Point oldPoint = FixedCircle.TransformToAncestor(this).Transform(new Point(centerX,centerY));
Point newPoint = FixedCircle.TransformToAncestor(this).Transform(new Point(0,centerY));
to indicate that transform must be set to starting pointg, I tried deleting this but the movement gets worse and starts from botton, or coordinate (0,0) is seen as the middle instead of (ActualWidth / 2, ActualHeight / 2) which is something I dont want.
TranslateTransform trans = new TranslateTransform();
FixedCircle.RenderTransform = trans;
Point oldPoint = FixedCircle.TransformToAncestor(this).Transform(new Point(centerX,centerY));
Point newPoint = FixedCircle.TransformToAncestor(this).Transform(new Point(0,centerY));
var EndX = FixedCircle.Width / 2 + newPoint.X - oldPoint.X - (FixedCircle.Width);
var EndY = FixedCircle.Height / 2 + newPoint.Y - oldPoint.Y - (FixedCircle.Height);
var a1X = new DoubleAnimation(0, EndX, TimeSpan.FromSeconds(3));
a1X.Completed += (s, e) =>
{
oldPoint = FixedCircle.TransformToAncestor(this).Transform(new Point(0, centerY));
newPoint = FixedCircle.TransformToAncestor(this).Transform(new Point(centerX, centerY));
EndX = FixedCircle.Width / 2 + newPoint.X - oldPoint.X - (FixedCircle.Width);
EndY = FixedCircle.Height / 2 + newPoint.Y - oldPoint.Y - (FixedCircle.Height);
var a2X = new DoubleAnimation(0, EndX, TimeSpan.FromSeconds(3));
trans.BeginAnimation(TranslateTransform.XProperty, a2X);
};
trans.BeginAnimation(TranslateTransform.XProperty, a1X);
The effect I get is ellipse correctly go from middle to left
then the issue of my problem, it starts in the middle and go to the right, when I need the ellipse to go from left to middle, not middle to right:
What am I missing?

The following code runs a repeated animation from middle to left and back. It uses a Path with an EllipseGeometry, because that is centered (instead of top/left aligned like an Ellipse). It also draws no stroke, but just adds the stroke thickness to the ellipse's radius.
var transform = new TranslateTransform(canvas.ActualWidth / 2, canvas.ActualHeight / 2);
var radius = 14;
var circle = new Path
{
Data = new EllipseGeometry(new Point(), radius, radius),
Fill = Brushes.White,
RenderTransform = transform
};
canvas.Children.Add(circle);
var animation = new DoubleAnimation
{
To = radius,
Duration = TimeSpan.FromSeconds(3),
AutoReverse = true,
RepeatBehavior = RepeatBehavior.Forever
};
transform.BeginAnimation(TranslateTransform.XProperty, animation);
For a repeated animation from right to left and back that starts at the center point, use a negative BeginTime:
var transform = new TranslateTransform(
canvas.ActualWidth - radius, canvas.ActualHeight / 2);
var animation = new DoubleAnimation
{
To = radius,
Duration = TimeSpan.FromSeconds(6),
AutoReverse = true,
RepeatBehavior = RepeatBehavior.Forever,
BeginTime = TimeSpan.FromSeconds(-3)
};

Refreshing picturebox stops other controls that need to redraw

So I have this steering wheel control, and when I rotate it with the mouse and refresh the image it stops my other panel control from drawing its graph from updating/redrawing. Below is the code for rotating and redrawing the steering wheel.
private readonly Bitmap _originalHelmImage;
private Bitmap _newHelmImage;
private void HelmPb_MouseDown(object sender, MouseEventArgs e)
{
if (e.Button != MouseButtons.Left) return;
PictureBox p = (PictureBox) sender;
Bitmap bmp = (Bitmap) p.Image;
//GetPixel works on initial image, not stretched one.
double ratio = (double) p.Image.Width/p.Width;
//Ignore the non-helm portion of the helm.
Color trans = bmp.GetPixel(Convert.ToInt32(ratio*e.X), Convert.ToInt32(ratio*e.Y));
if (trans.A.Equals(0))
{
_dontTurn = true;
return;
}
_offsetAngle = OffsetAngle() - _lastAngleTurn;
_lastAngleTurn = 0;
_dontTurn = false;
}
private double OffsetAngle()
{
int helmXMid = HelmPb.PointToScreen(Point.Empty).X + (HelmPb.Width / 2);
int helmYMid = HelmPb.PointToScreen(Point.Empty).Y + (HelmPb.Height / 2);
double angle = AngleFromPoints(MousePosition, new Point(helmXMid, helmYMid));
return angle;
}
private void HelmPb_MouseMove(object sender, MouseEventArgs e)
{
if ((e.Button != MouseButtons.Left) || _dontTurn) return;
double angle = OffsetAngle();
float degrees = Convert.ToSingle(angle - _offsetAngle);
//float diff = ((360 - degrees) - _deltaHelmTurn%360)%360;
//float diff = (_lastAngleTurn - (degrees - 360)) % 360;
double diff = 90 - angle;
_deltaHelmTurn += Convert.ToSingle(diff - _lastAngleTurn);
if (Math.Abs(_deltaHelmTurn) >= (_maxHelmTurn*360.0))
{
_deltaHelmTurn = Convert.ToSingle(_maxHelmTurn*360.0);
degrees = 0;
}
_lastAngleTurn = Convert.ToSingle(degrees);
_newHelmImage = RotateImage(_originalHelmImage, -degrees);
HelmPb.Image.Dispose();
HelmPb.Image = _newHelmImage;
WaterDepthPlot.Invalidate();
HelmPb.Refresh();
}
double AngleFromPoints(Point pt1, Point pt2)
{
Point p = new Point(pt1.X - pt2.X, pt1.Y - pt2.Y);
double alpha;
if (p.Y == 0) alpha = p.X > 0 ? 0d : 180d;
else
{
double f = 1d * p.X / (Math.Sqrt(p.X * p.X + p.Y * p.Y));
alpha = Math.Acos(f) * 180d / Math.PI;
if (p.Y > 0) alpha = 360d - alpha;
}
return alpha;
}
private Bitmap RotateImage(Bitmap b, float angle)
{
//Create a new empty bitmap to hold rotated image.
Bitmap returnBitmap = new Bitmap(b.Width, b.Height);
//Make a graphics object from the empty bitmap.
Graphics g = Graphics.FromImage(returnBitmap);
//move rotation point to center of image.
g.InterpolationMode = InterpolationMode.HighQualityBicubic;
g.TranslateTransform(b.Width/2F, b.Height/2F);
//Rotate.
g.RotateTransform(angle);
//Move image back.
g.TranslateTransform(-b.Width/2F, -b.Height/2F);
//Draw passed in image onto graphics object.
g.DrawImage(b, new PointF(0.0F, 0.0F));
return returnBitmap;
}
Below is the code for updating my graph. It is never ran when the steering wheel is being moved. Once the users stops moving, it will update. Is there a way for it to constantly update along with it? I tried throwing a refresh/invalidate of the panel into the mousemove event so whenever the wheel is refreshed, so is the graph; no luck. Any suggestions?
private void WaterDepthPlot_Paint(object sender, PaintEventArgs e)
{
Pen pen = new Pen(Color.FromArgb(70, 75, 80));
int xOffset = WaterDepthPlot.Location.X;
e.Graphics.DrawLine(pen, new Point(0, 0), new Point(WaterDepthPlot.Width, 0));
e.Graphics.DrawLine(pen, new Point(0, (WaterDepthPlot.Height/5)),
new Point(WaterDepthPlot.Width, (WaterDepthPlot.Height/5)));
e.Graphics.DrawLine(pen, new Point(0, (2*WaterDepthPlot.Height/5)),
new Point(WaterDepthPlot.Width, (2*WaterDepthPlot.Height/5)));
e.Graphics.DrawLine(pen, new Point(0, (3*WaterDepthPlot.Height/5)),
new Point(WaterDepthPlot.Width, (3*WaterDepthPlot.Height/5)));
e.Graphics.DrawLine(pen, new Point(0, (4*WaterDepthPlot.Height/5)),
new Point(WaterDepthPlot.Width, (4*WaterDepthPlot.Height/5)));
e.Graphics.DrawLine(pen, new Point((ThirdXScaleUnit.Location.X - xOffset), 0),
new Point((ThirdXScaleUnit.Location.X - xOffset),
(WaterDepthPlot.Height + WaterDepthPlot.Location.Y)));
e.Graphics.DrawLine(pen, new Point((SecondXScaleUnit.Location.X - xOffset), 0),
new Point((SecondXScaleUnit.Location.X - xOffset),
(WaterDepthPlot.Height + WaterDepthPlot.Location.Y)));
e.Graphics.DrawLine(pen, new Point((FirstXScaleUnit.Location.X - xOffset), 0),
new Point((FirstXScaleUnit.Location.X - xOffset),
(WaterDepthPlot.Height + WaterDepthPlot.Location.Y)));
pen = new Pen(Color.Firebrick);
pen.DashStyle = DashStyle.Dash;
float[] dash = {3, 3};
pen.DashPattern = dash;
double diff = (double) WaterDepthPlot.Height/(5*_depthYScale);
int alertDiff = (int)(_alertDepth * diff);
e.Graphics.DrawLine(pen, new Point(0, alertDiff), new Point(WaterDepthPlot.Width, alertDiff));
pen = new Pen(Color.White);
GraphicsPath gp = new GraphicsPath();
if (_depthCurve.Count < 2) return;
gp.AddCurve(_depthCurve.ToArray());
e.Graphics.DrawPath(pen, gp);
}

How to find the coordinates of the mouse in the background image winform c#

I have a BufferedGraphics painted in the panel. The image is zoomed in and zoomed out. From this buffered graphic images how can i find the mouse position in the image not in the panel.
private void panel2_paint(object sender, PaintEventArgs e)
{
if (bitmap != null)
{
float widthZoomed = panel2.Width / Zoom;
float heigthZoomed = panel2.Height / Zoom;
if (widthZoomed > 30000.0f)
{
Zoom = panel2.Width / 30000.0f;
widthZoomed = 30000.0f;
}
if (heigthZoomed > 30000.0f)
{
Zoom = panel2.Height / 30000.0f;
heigthZoomed = 30000.0f;
}
if (widthZoomed < 2.0f)
{
Zoom = panel2.Width / 2.0f;
widthZoomed = 2.0f;
}
if (heigthZoomed < 2.0f)
{
Zoom = panel2.Height / 2.0f;
heigthZoomed = 2.0f;
}
float wz2 = widthZoomed / 2.0f;
float hz2 = heigthZoomed / 2.0f;
Rectangle drawRect = new Rectangle(
(int)(viewPortCenter.X - wz2),
(int)(viewPortCenter.Y - hz2),
(int)(widthZoomed),
(int)(heigthZoomed));
drawrecX = drawRect.X;
drawrecY = drawRect.Y;
dispwidth = (int)(widthZoomed);
dispheight = (int)(heigthZoomed);
myBuffer.Graphics.Clear(Color.White); //Clear the Back buffer
Console.WriteLine(this.panel2.DisplayRectangle.Width);
Console.WriteLine(this.panel2.DisplayRectangle.Height);
myBuffer.Graphics.DrawImage(bitmap, this.panel2.DisplayRectangle, drawRect, GraphicsUnit.Pixel);
//pictureBox1.Image =
myBuffer.Render(this.panel2.CreateGraphics());
//this.toolStripStatusLabel1.Text = "Zoom: " + ((int)(this.Zoom * 100)).ToString() + "%";
}
}
the above code is the paint part.
To find the location of the mouse in the image i tried like this
private void panel2_DoubleClick(object sender, EventArgs e)
{
var mouseArgs = (MouseEventArgs)e;
double Pic_width = dispwidth / panel2.Width;//to find the relative position
double Pic_height = dispheight / panel2.Height;
int xpoint = (int)Pic_width * mouseArgs.X + drawrecX;//drawrecX is the X coordinate from the drawing image
int ypoint = (int)Pic_height * mouseArgs.Y + drawrecY;
}
but this code does not give me the exact position. any idea?

Try this:
private void panel2_DoubleClick(object sender, EventArgs e)
{
var mouseArgs = (MouseEventArgs)e;
int x = mouseArgs.X - drawrecX;
int y = mouseArgs.Y - drawrecY;
var size = ImageSizeWithoutZoom;
var zoomSize = ImageSizeWithZoom;
double xPoint = x * size.X / zoomSize.X;
double yPoint = y * size.Y / zoomSize.Y;
}

Printing Image from Silverlight

I'm trying to print a Image in Landscape mode in Silverlight.
I found a great example here. Where most of the code comes from. The code worked perfectly as expected. When I changed the Line to an Image it failed.
Code
Canvas OuterCanvas = new Canvas();
/* a container for everything that will print */
Border OuterBorder = new Border()
{
BorderThickness = new Thickness(3),
BorderBrush = new SolidColorBrush(Colors.Red),
Margin = new Thickness(10)
};
double Width = e.PrintableArea.Width - OuterBorder.Margin.Left - OuterBorder.Margin.Right;
double Height = e.PrintableArea.Height - OuterBorder.Margin.Top - OuterBorder.Margin.Bottom;
/* NOTE: We're trying to force landscape, so swop the width and height */
OuterBorder.Width = Height;
OuterBorder.Height = Width;
/* on portrait, this line goes down (leave the printer settings, we're trying to force landscape) */
Line Line = new Line()
{
X1 = OuterBorder.Width / 2,
Y1 = 0,
X2 = OuterBorder.Width / 2,
Y2 = OuterBorder.Height,
Stroke = new SolidColorBrush(Colors.Blue),
StrokeThickness = 3
};
//
// Here is where I changed the Line to an Image
//
OuterBorder.Child = imageElementInXaml; //Line;
OuterCanvas.Children.Add(OuterBorder);
/* rotate 90 degrees, and move into place */
var transformGroup = new TransformGroup();
transformGroup.Children.Add(new RotateTransform() { Angle = 90 });
transformGroup.Children.Add(new TranslateTransform() { X = e.PrintableArea.Width });
OuterBorder.RenderTransform = transformGroup;
e.PageVisual = OuterCanvas;
e.HasMorePages = false;
I know that a Border can only contain 1 element in which I have done so, and when I printed the image on its own without trying to make it landscape this worked too. So why wont it work when I simply replace the Line with the image Element

So since posting this I found some code (cant remember where now) that has helped me get the printing working. Its not as clean as I would have liked but it works.
void pd_PrintPage(object sender, PrintPageEventArgs e)
{
Image image = new Image();
image.Source = imgPlayer.Source;
//This is important
image.Stretch = Stretch.Uniform;
// Find the full size of the page
Size pageSize = new Size(e.PrintableArea.Width + e.PageMargins.Left + e.PageMargins.Right, e.PrintableArea.Height + e.PageMargins.Top + e.PageMargins.Bottom);
var MARGIN= 10;
// Get additional margins to bring the total to MARGIN (= 96)
Thickness additionalMargin = new Thickness
{
Left = Math.Max(0, MARGIN - e.PageMargins.Left),
Top = Math.Max(0, MARGIN - e.PageMargins.Top),
Right = Math.Max(0, MARGIN - e.PageMargins.Right),
Bottom = Math.Max(0, MARGIN - e.PageMargins.Bottom)
};
// Find the area for display purposes
Size displayArea = new Size(e.PrintableArea.Width - additionalMargin.Left - additionalMargin.Right, e.PrintableArea.Height - additionalMargin.Top - additionalMargin.Bottom);
bool pageIsLandscape = displayArea.Width > displayArea.Height;
bool imageIsLandscape = image.ActualWidth > image.ActualHeight;
double displayAspectRatio = displayArea.Width / displayArea.Height;
double imageAspectRatio = (double)image.ActualWidth / image.ActualHeight;
double scaleX = Math.Min(1, imageAspectRatio / displayAspectRatio);
double scaleY = Math.Min(1, displayAspectRatio / imageAspectRatio);
// Calculate the transform matrix
MatrixTransform transform = new MatrixTransform();
if (pageIsLandscape == imageIsLandscape)
{
// Pure scaling
transform.Matrix = new Matrix(scaleX, 0, 0, scaleY, 0, 0);
}
else
{
// Scaling with rotation
scaleX *= pageIsLandscape ? displayAspectRatio : 1 / displayAspectRatio;
scaleY *= pageIsLandscape ? displayAspectRatio : 1 / displayAspectRatio;
transform.Matrix = new Matrix(0, scaleX, -scaleY, 0, 0, 0);
}
Image image2 = new Image
{
Source = image.Source,
Stretch = Stretch.Fill,
Width = displayArea.Width,
Height = displayArea.Height,
RenderTransform = transform,
RenderTransformOrigin = new Point(0.5, 0.5),
HorizontalAlignment = HorizontalAlignment.Center,
VerticalAlignment = VerticalAlignment.Center,
Margin = additionalMargin,
};
Border border = new Border
{
Child = image,
};
e.PageVisual = border;
}