image resize and crop on upload asp,net - asp.net

Question

i have the below code, i am looking to crop and resize at the same time, i use the below function, i am looking to have 150 x 150 px image size cropped centered, but the below function always if the image width > height, the output image will be 200x150, but i need it to be 150x150 px,, any help
Function SavetoDisk(FU As FileUpload, ByVal para_Save_to_Path As String, ByVal maxHeight As Integer, ByVal maxWidth As Integer, para_FileExt As String, anchor As AnchorPosition)
Using image As Image = image.FromStream(FU.PostedFile.InputStream)
Dim sourceWidth As Integer = image.Width
Dim sourceHeight As Integer = image.Height
Dim sourceX As Integer = 0
Dim sourceY As Integer = 0
Dim destX As Integer = 0
Dim destY As Integer = 0
Dim nPercent As Decimal = 0
Dim nPercentW As Decimal = 0
Dim nPercentH As Decimal = 0
nPercentW = (Convert.ToSingle(maxWidth) / Convert.ToSingle(sourceWidth))
nPercentH = (Convert.ToSingle(maxHeight) / Convert.ToSingle(sourceHeight))
If (nPercentH < nPercentW) Then
nPercent = nPercentW
Select Case (anchor)
Case AnchorPosition.Top
destY = 0
Case AnchorPosition.Bottom
destY = Convert.ToInt32(maxHeight - (sourceHeight * nPercent))
Case Else
destY = Convert.ToInt32((maxHeight - (sourceHeight * nPercent)) / 2)
End Select
Else
nPercent = nPercentH
Select Case (anchor)
Case AnchorPosition.Left
destX = 0
Case AnchorPosition.Right
destX = Convert.ToInt32((maxWidth - (sourceWidth * nPercent)))
Case Else
destX = Convert.ToInt32(((maxWidth - (sourceWidth * nPercent)) / 2))
End Select
End If
Dim destWidth As Integer = Convert.ToInt32((sourceWidth * nPercent))
Dim destHeight As Integer = Convert.ToInt32((sourceHeight * nPercent))
Using thumbnailBitmap As Bitmap = New Bitmap(destWidth, destHeight)
Using thumbnailGraph As Graphics = Graphics.FromImage(thumbnailBitmap)
thumbnailGraph.CompositingQuality = CompositingQuality.HighQuality
thumbnailGraph.SmoothingMode = SmoothingMode.HighQuality
thumbnailGraph.InterpolationMode = InterpolationMode.HighQualityBicubic
Dim imageRectangle As Rectangle = New Rectangle(0, 0, destHeight, destHeight)
thumbnailGraph.DrawImage(image, New Rectangle(destX, destY, destWidth, destHeight), New Rectangle(sourceX, sourceY, sourceWidth, sourceHeight), GraphicsUnit.Pixel)
Dim jpegCodec As ImageCodecInfo = Findcodecinfo("JPEG")
If Not IsNothing(jpegCodec) Then
Dim encoderParameters As EncoderParameters = New EncoderParameters(1)
encoderParameters.Param(0) = New EncoderParameter(Encoder.Quality, 80)
thumbnailBitmap.Save(para_Save_to_Path, jpegCodec, encoderParameters)
Else
thumbnailBitmap.Save(para_Save_to_Path, ImageFormat.Jpeg)
End If
End Using
End Using
End Using
End Function

Answer 1

Steps to achieve what you want:
Figure out ratio of height to width
Scale the larger dimension down to 150px and the smaller dimension down to ratio * 150px.
Draw the result in the middle of a 150x150 bitmap.
This code will do exactly that (c#):
using ( Image img = Image.FromStream( FU.PostedFile.InputStream ) )
{
int sourceWidth = img.Width;
int sourceHeight = img.Height;
int desiredHeight = 150;
int desiredWidth = 150;
double heightToWidthRatio = sourceHeight / ( double )sourceWidth;
//This draw method will always center the image horizonally or vertically, as appropriate
using ( Bitmap thumbnailBitmap = new Bitmap( desiredWidth, desiredHeight ) )
{
using ( Graphics thumbnailGraph = Graphics.FromImage( thumbnailBitmap ) )
{
thumbnailGraph.CompositingQuality = CompositingQuality.HighQuality;
thumbnailGraph.SmoothingMode = SmoothingMode.HighQuality;
thumbnailGraph.InterpolationMode = InterpolationMode.HighQualityBicubic;
float destWidth = ( heightToWidthRatio > 1f ) ? ( float )( desiredWidth / heightToWidthRatio ) : desiredWidth;
float destHeight = ( heightToWidthRatio > 1f ) ? desiredHeight : ( float )( desiredHeight * heightToWidthRatio );
float destX = ( desiredWidth - destWidth ) / 2f;
float destY = ( desiredHeight - destHeight ) / 2f;
thumbnailGraph.DrawImage( img, new RectangleF( destX, destY, destWidth, destHeight ),
new Rectangle( sourceWidth, sourceHeight, sourceWidth, sourceHeight ),
GraphicsUnit.Pixel );
}
}
}
Continue to write out the file as you have been, previously.
The important part is the four float values in the middle and the fact that it uses a RectangleF in the DrawImage function, to truly center, even on fractional values.
If you do not want that behavior due to excessive antialiasing, just Math.Floor the values and continue to use Rectangle and ints.