Rounded Bitmap Corners

Question

User1725247990 posted

Hi there

I'm trying to create rounded corners on images programmatically. Is there an easy way to do this using Graphics.DrawImage function? I've used the following code to cut out a rectangle withing the image but how can i create a rectangle with rounded corners to use instead? any ideas?

Dim mybitmap as Bitmap = Image.fromfile( Server.Mappath("myimage.jpg") )

Dim cropbitmap as Bitmap = new Bitmap(500, 360)

Dim mygraphic as Graphics = Graphics.FromImage(cropbitmap)

mygraphic.DrawImage(mybitmap, new Rectangle(5,5,490,350),new Rectangle(0,0,500,360),GraphicsUnit.Pixel)

response.contenttype="image/jpeg"

cropbitmap.save(response.outputstream, imageformat.jpeg)

mygraphic.dispose()

cropbitmap.dispose()

mybitmap.dispose()

Answer 1

User1725247990 posted

found the answer

<%@ Page Language="C#" %>
<%@ Import Namespace="System.Drawing" %>
<script runat="server">

    void Page_Init(Object sender,EventArgs e) {

        string path = Server.MapPath("~/Images/flower.jpg");
        int roundedDia = 50;

       
            using(Image imgin = Image.FromFile(path)){
            Bitmap bitmap = new Bitmap(imgin.Width, imgin.Height);
            Graphics g = Graphics.FromImage(bitmap);
            g.Clear(Color.White);
            g.SmoothingMode =
(System.Drawing.Drawing2D.SmoothingMode.AntiAlias);
            Brush brush = new System.Drawing.TextureBrush(imgin);
            FillRoundedRectangle(g,
new Rectangle(0, 0, imgin.Width, imgin.Height),
roundedDia, brush);

// done with drawing dispose graphics object.
            g.Dispose();
            // Stream Image to client.
            Response.Clear();
            Response.ContentType = "image/pjpeg";
            bitmap.Save(Response.OutputStream,
System.Drawing.Imaging.ImageFormat.Jpeg);
            Response.End();
// dispose bitmap object.
            bitmap.Dispose();
           
        }
    }

    public static void FillRoundedRectangle(Graphics g,
Rectangle r,int d,Brush b){

        System.Drawing.Drawing2D.GraphicsPath gp
= new System.Drawing.Drawing2D.GraphicsPath();

        gp.AddArc(r.X, r.Y, d, d, 180, 90);
        gp.AddArc(r.X + r.Width - d, r.Y, d, d, 270, 90);
        gp.AddArc(r.X + r.Width - d, r.Y + r.Height - d, d, d, 0, 90);
        gp.AddArc(r.X, r.Y + r.Height - d, d, d, 90, 90);

        g.FillPath(b, gp);
    }
</script>

courtesy of http://www.jigar.net/howdoi/viewhtmlcontent98.aspx

Answer 2

User1980424205 posted

Hi

Does anybody know how to do this in VB? Ideally I'd like to run this on file upload and actually save the rounded image as a new file, rather than just generating it on-the-fly. But if anyone can translate this to VB, that'd be marvellous (code converters just don't work).

Thanks

Answer 3

User1980424205 posted

Not to worry, I worked it out:

Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load

Dim path As String = Server.MapPath("flower.jpg")

Dim roundedDia As Integer = 50

 

Using imgin As System.Drawing.Image = System.Drawing.Image.FromFile(path)

Dim bitmap As Drawing.Bitmap = New Drawing.Bitmap(imgin.Width, imgin.Height)

Dim g As Drawing.Graphics = Drawing.Graphics.FromImage(bitmap)

g.Clear(System.Drawing.Color.White)

g.SmoothingMode = (System.Drawing.Drawing2D.SmoothingMode.AntiAlias)

Dim brush As Drawing.Brush = New System.Drawing.TextureBrush(imgin)

FillRoundedRectangle(g, New Drawing.Rectangle(0, 0, imgin.Width, imgin.Height), roundedDia, brush)

' done with drawing dispose graphics object.

g.Dispose()

' Stream Image to client.

Response.Clear()

Response.ContentType = "image/pjpeg"

bitmap.Save(Response.OutputStream, System.Drawing.Imaging.ImageFormat.Jpeg)

bitmap.Save(Server.MapPath("flower3.jpg"))

Response.End()

' dispose bitmap object.

bitmap.Dispose()

End Using

End Sub

Public Shared Sub FillRoundedRectangle(ByVal g As Drawing.Graphics, ByVal r As Drawing.Rectangle, ByVal d As Integer, ByVal b As Drawing.Brush)

Dim gp As System.Drawing.Drawing2D.GraphicsPath = New System.Drawing.Drawing2D.GraphicsPath()

gp.AddArc(r.X, r.Y, d, d, 180, 90)

gp.AddArc(r.X + r.Width - d, r.Y, d, d, 270, 90)

gp.AddArc(r.X + r.Width - d, r.Y + r.Height - d, d, d, 0, 90)

gp.AddArc(r.X, r.Y + r.Height - d, d, d, 90, 90)

g.FillPath(b, gp)

End Sub