Say, i have a PictureBox1 in my Form. That PictureBox have an Image in it, and I want to rotate it. Actually, I've learn how to rotate the image by 90,180,270.... degree. But how can I rotate it by 20 degrees or 45 degrees?
This is what I've learn
PictureBox1.Image.RotateFlip(RotateFlipType.Rotate90FlipNone)
My solution:
Public Function RotateImage(ByRef image As Image, ByVal offset As PointF, ByVal angle As Decimal) As Bitmap
If image Is Nothing Then
Throw New ArgumentNullException("image")
End If
''create a new empty bitmap to hold rotated image
Dim rotatedBmp As Bitmap = New Bitmap(image.Width, image.Height)
'Dim rotatedBmp As Bitmap = New Bitmap(image)
rotatedBmp.SetResolution(image.HorizontalResolution, image.VerticalResolution)
''make a graphics object from the empty bitmap
Dim g As Graphics = Graphics.FromImage(rotatedBmp)
''Put the rotation point in the center of the image
g.TranslateTransform(offset.X, offset.Y)
''rotate the image
g.RotateTransform(angle)
''move the image back
g.TranslateTransform(-offset.X, -offset.Y)
''draw passed in image onto graphics object
'g.DrawImage(image, New PointF(0, 0))
g.DrawImage(image, offset)
Return rotatedBmp
End Function
Related
I am looking for a function to take a screenshot from an embedded Windows Media Player control in a VB.NET Windows form. I am currently using the following function; it works fine, but the problem is that x and y are different on each screen so it would be better if I could use a function in the AxWindowsMediaPlayer control itself, like .Capture() or a similar method.
Private Function TakeImage(ByVal X As Integer, ByVal Y As Integer, ByVal Width As Integer, ByVal Height As Integer) As Bitmap
Dim Img As New Bitmap(Width, Height)
Dim g As Graphics = Graphics.FromImage(Img)
g.CopyFromScreen(X, Y, 0, 0, Img.Size)
g.Dispose()
Return Img
End Function
Dim bmp As Bitmap = TakeImage(x, y - 20, AxWindowsMediaPlayer1.Width, AxWindowsMediaPlayer1.Height)
bmp.Save("E:\pics\" & i.ToString & ".jpg", Drawing.Imaging.ImageFormat.Jpeg)
You could try Ctl.PointToScreen() to get an absolute screen point for CopyFromScreen.
I would get the AxWMP.PointToScreen in the procedure each time since the form could move. Pass them to CopyFromScreen and see if that works. I am not sure if it expects X,Y relative to the app, form or what but Screen, does mean screen.
This question already exists:
Closed 10 years ago.
Possible Duplicate:
VB.NET replace pixel color of picturebox image
i want to extract square from full picture
full pic:
i want only this:
With this Function should work:
Public Function GetPicturePart(ByVal SourceImage As Image, ByVal Region As Rectangle) As Bitmap
Dim ImagePart As Bitmap = New Bitmap(Region.Width, Region.Height)
Using G As Graphics = Graphics.FromImage(ImagePart)
Dim TargetRect As Rectangle = New Rectangle(0, 0, Region.Width, Region.Height)
Dim SourceRect As Rectangle = Region
G.DrawImage(SourceImage, TargetRect, SourceRect, GraphicsUnit.Pixel)
End Using
Return ImagePart
End Function
I think this function is self-describing. ;)
Source: Get Picture Part
In VB.NET, I need to create an Image based on a Graphics object I have. However, there is no method such as Image.fromGraphics() etc. What should I do then?
Try something like this MSDN article states. Essentialy create a Graphics Object from a Bitmap. Then use Graphic methods to do what you need to to the Image and then you can use the Image how you need to. As #Damien_The_Unbeliever stated your Graphics Object is created to enable drawing on another object, it does not have an Image to copy, the object it was created on does.
From above article:
Dim flag As New Bitmap(200, 100)
Dim flagGraphics As Graphics = Graphics.FromImage(flag)
Dim red As Integer = 0
Dim white As Integer = 11
While white <= 100
flagGraphics.FillRectangle(Brushes.Red, 0, red, 200, 10)
flagGraphics.FillRectangle(Brushes.White, 0, white, 200, 10)
red += 20
white += 20
End While
pictureBox1.Image = flag
Have a look at the Graphics.DrawImage method and its overloads.
Here's a snippet from one of the examples that draws an image onto the screen, using a Graphics object from Winform's Paint event:
Private Sub DrawImageRect(ByVal e As PaintEventArgs)
' Create image.
Dim newImage As Image = Image.FromFile("SampImag.jpg")
' Create rectangle for displaying image.
Dim destRect As New Rectangle(100, 100, 450, 150)
' Draw image to screen.
e.Graphics.DrawImage(newImage, destRect)
End Sub
I want pixel color value of the picturebox
I assigned text to the picturebox & now want to get the value of color of each pixel
What is method of picturebox or i should convert it to bitmap? How?
in vb6 there is getpixel() method to get color value
What is in .net?
If you can convert it into a bitmap, it's a breeze:
Dim MyBitmap As New Bitmap(MyPicturebox.Image)
Dim MyColor As Color
MyColor = MyBitmap.GetPixel(X of your pixel, Y of your pixel)
You might want to loop through the pixels, which is not hard if you know the width and height.
Okay, I've learned a bit more and have rephrased my question. I've got a need to flip or invert text 180 degrees (so it appears upside-down) on a RDLC report. I have some custom VB code that takes the text, converts it to a bitmap, then flips the rotates the canvas 180 degrees. The effect of this makes the text look a bit.. dithered... or fuzzy. It's not a sharp font anymore. The problem I'm experiencing is I'm using a special TTF Barcode font that creates something a scanner can read. When I flip the barcode font, the fuzziness isn't good since the barcode lines are so close together and the scanner cannot read it. Here's the code:
Function LoadImage(ByVal sImageText as String, iRotationAngle as Integer, ByVal sFontName as String, iFontSize as Integer)
Dim bmpImage As New Drawing.Bitmap(1, 1)
Dim iWidth As Integer = 0
Dim iHeight As Integer = 0
'// Create the Font object for the image text drawing.
Dim MyFont As New Drawing.Font(sFontName, iFontSize) ', System.Drawing.FontStyle.Bold, System.Drawing.GraphicsUnit.Point)
'// Create a graphics object to measure the text's width and height.
Dim MyGraphics As Drawing.Graphics = Drawing.Graphics.FromImage(bmpImage)
'// This is where the bitmap size is determined.
iWidth = MyGraphics.MeasureString(sImageText, MyFont).Width
iHeight = MyGraphics.MeasureString(sImageText, MyFont).Height
'// Create the bmpImage again with the correct size for the text and font.
bmpImage = New Drawing.Bitmap(bmpImage, New Drawing.Size(iWidth, iHeight))
'// Add the colors to the new bitmap.
MyGraphics = Drawing.Graphics.FromImage(bmpImage)
MyGraphics.Clear(Drawing.Color.White)
MyGraphics.TextRenderingHint = Drawing.Text.TextRenderingHint.ClearTypeGridFit
MyGraphics.TranslateTransform(iWidth,iHeight)
MyGraphics.RotateTransform(iRotationAngle)
MyGraphics.DrawString(sImageText, MyFont, New Drawing.SolidBrush(Drawing.Color.Black), 0, 0)
MyGraphics.Flush()
Dim stream As IO.MemoryStream = New IO.MemoryStream
Dim bitmapBytes As Byte()
'Create bitmap
bmpImage.Save(stream, System.Drawing.Imaging.ImageFormat.Bmp)
bitmapBytes = stream.ToArray
stream.Close()
bmpImage.Dispose()
Return bitmapBytes
End Function
I really don't know why there's not a built-in way to just flip text. It'll let me reverse it left-to-right. Ridiculous.
Thanks