resizing images

Imports System.Threading
Imports System.Data.SqlClient
Imports System.Data
Imports System.Drawing
Imports System.Drawing.Imaging
Imports System.IO
Imports System.Drawing.Drawing2D
 
Partial Class admin_test
    Inherits System.Web.UI.Page
    Protected savePath As String = "~/thumbnails/"
    Private Shared Function resizeImage(ByVal imgToResize As Image, ByVal size As Size) As Image
        Dim sourceWidth As Integer = imgToResize.Width
        Dim sourceHeight As Integer = imgToResize.Height
 
        Dim nPercent As Single = 0
        Dim nPercentW As Single = 0
        Dim nPercentH As Single = 0
 
        nPercentW = (CSng(size.Width) / CSng(sourceWidth))
        nPercentH = (CSng(size.Height) / CSng(sourceHeight))
 
        If nPercentH < nPercentW Then
            nPercent = nPercentH
        Else
            nPercent = nPercentW
        End If
 
        Dim destWidth As Integer = CInt((sourceWidth * nPercent))
        Dim destHeight As Integer = CInt((sourceHeight * nPercent))
 
        Dim b As New Bitmap(destWidth, destHeight)
        Dim g As Graphics = Graphics.FromImage(DirectCast(b, Image))
        g.InterpolationMode = InterpolationMode.HighQualityBicubic
 
        g.DrawImage(imgToResize, 0, 0, destWidth, destHeight)
        g.Dispose()
 
        Return DirectCast(b, Image)
    End Function
 
    Protected Sub Upload(ByVal sender As Object, ByVal e As System.EventArgs)
 
 
        If FileUpload1.FileName <> "" Then
 
            'thubnail creation and upload
            Dim fileName As String = FileUpload1.FileName
            Dim src As Bitmap = TryCast(Bitmap.FromStream(FileUpload1.PostedFile.InputStream), Bitmap)
            Dim resultThumb As Bitmap = resizeImage(src, src.Size)
            Dim saveName As String = Server.MapPath(savePath) + fileName
            resultThumb.Save(saveName, ImageFormat.Jpeg)
        End If
    End Sub
 
End Class

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using System;
using System.Drawing;
using System.Drawing.Imaging;
using System.Drawing.Drawing2D;
 
namespace Tutorial
{
	class ImageResize
	{
		enum Dimensions 
		{
			Width,
			Height
		}
		enum AnchorPosition
		{
			Top,
			Center,
			Bottom,
			Left,
			Right
		}
		[STAThread]
		static void Main(string[] args)
		{
			//set a working directory
			string WorkingDirectory = @"C:\Projects\Tutorials\ImageResize";
 
			//create a image object containing a verticel photograph
			Image imgPhotoVert = Image.FromFile(WorkingDirectory + @"\imageresize_vert.jpg");
			Image imgPhotoHoriz = Image.FromFile(WorkingDirectory + @"\imageresize_horiz.jpg");
			Image imgPhoto = null;
 
			imgPhoto = ScaleByPercent(imgPhotoVert, 50);
			imgPhoto.Save(WorkingDirectory + @"\images\imageresize_1.jpg", ImageFormat.Jpeg);
			imgPhoto.Dispose();
 
			imgPhoto = ConstrainProportions(imgPhotoVert, 200, Dimensions.Width);
			imgPhoto.Save(WorkingDirectory + @"\images\imageresize_2.jpg", ImageFormat.Jpeg);
			imgPhoto.Dispose();
 
			imgPhoto = FixedSize(imgPhotoVert, 200, 200);
			imgPhoto.Save(WorkingDirectory + @"\images\imageresize_3.jpg", ImageFormat.Jpeg);
			imgPhoto.Dispose();
 
			imgPhoto = Crop(imgPhotoVert, 200, 200, AnchorPosition.Center);
			imgPhoto.Save(WorkingDirectory + @"\images\imageresize_4.jpg", ImageFormat.Jpeg);
			imgPhoto.Dispose();
 
			imgPhoto = Crop(imgPhotoHoriz, 200, 200, AnchorPosition.Center);
			imgPhoto.Save(WorkingDirectory + @"\images\imageresize_5.jpg", ImageFormat.Jpeg);
			imgPhoto.Dispose();
 
		}
		static Image ScaleByPercent(Image imgPhoto, int Percent)
		{
			float nPercent = ((float)Percent/100);
 
			int sourceWidth = imgPhoto.Width;
			int sourceHeight = imgPhoto.Height;
			int sourceX = 0;
			int sourceY = 0;
 
			int destX = 0;
			int destY = 0; 
			int destWidth  = (int)(sourceWidth * nPercent);
			int destHeight = (int)(sourceHeight * nPercent);
 
			Bitmap bmPhoto = new Bitmap(destWidth, destHeight, PixelFormat.Format24bppRgb);
			bmPhoto.SetResolution(imgPhoto.HorizontalResolution, imgPhoto.VerticalResolution);
 
			Graphics grPhoto = Graphics.FromImage(bmPhoto);
			grPhoto.InterpolationMode = InterpolationMode.HighQualityBicubic;
 
			grPhoto.DrawImage(imgPhoto, 
				new Rectangle(destX,destY,destWidth,destHeight),
				new Rectangle(sourceX,sourceY,sourceWidth,sourceHeight),
				GraphicsUnit.Pixel);
 
			grPhoto.Dispose();
			return bmPhoto;
		}
		static Image ConstrainProportions(Image imgPhoto, int Size, Dimensions Dimension)
		{
			int sourceWidth = imgPhoto.Width;
			int sourceHeight = imgPhoto.Height;
			int sourceX = 0;
			int sourceY = 0;
			int destX = 0;
			int destY = 0; 
			float nPercent = 0;
 
			switch(Dimension)
			{
				case Dimensions.Width:
					nPercent = ((float)Size/(float)sourceWidth);
					break;
				default:
					nPercent = ((float)Size/(float)sourceHeight);
					break;
			}
				
			int destWidth  = (int)(sourceWidth * nPercent);
			int destHeight = (int)(sourceHeight * nPercent);
 
			Bitmap bmPhoto = new Bitmap(destWidth, destHeight, PixelFormat.Format24bppRgb);
			bmPhoto.SetResolution(imgPhoto.HorizontalResolution, imgPhoto.VerticalResolution);
 
			Graphics grPhoto = Graphics.FromImage(bmPhoto);
			grPhoto.InterpolationMode = InterpolationMode.HighQualityBicubic;
 
			grPhoto.DrawImage(imgPhoto, 
			new Rectangle(destX,destY,destWidth,destHeight),
			new Rectangle(sourceX,sourceY,sourceWidth,sourceHeight),
			GraphicsUnit.Pixel);
 
			grPhoto.Dispose();
			return bmPhoto;
		}
 
		static Image FixedSize(Image imgPhoto, int Width, int Height)
		{
			int sourceWidth = imgPhoto.Width;
			int sourceHeight = imgPhoto.Height;
			int sourceX = 0;
			int sourceY = 0;
			int destX = 0;
			int destY = 0; 
 
			float nPercent = 0;
			float nPercentW = 0;
			float nPercentH = 0;
 
			nPercentW = ((float)Width/(float)sourceWidth);
			nPercentH = ((float)Height/(float)sourceHeight);
 
			//if we have to pad the height pad both the top and the bottom
			//with the difference between the scaled height and the desired height
			if(nPercentH < nPercentW)
			{
				nPercent = nPercentH;
				destX = (int)((Width - (sourceWidth * nPercent))/2);
			}
			else
			{
				nPercent = nPercentW;
				destY = (int)((Height - (sourceHeight * nPercent))/2);
			}
		
			int destWidth  = (int)(sourceWidth * nPercent);
			int destHeight = (int)(sourceHeight * nPercent);
 
			Bitmap bmPhoto = new Bitmap(Width, Height, PixelFormat.Format24bppRgb);
			bmPhoto.SetResolution(imgPhoto.HorizontalResolution, imgPhoto.VerticalResolution);
 
			Graphics grPhoto = Graphics.FromImage(bmPhoto);
			grPhoto.Clear(Color.Red);
			grPhoto.InterpolationMode = InterpolationMode.HighQualityBicubic;
 
			grPhoto.DrawImage(imgPhoto, 
				new Rectangle(destX,destY,destWidth,destHeight),
				new Rectangle(sourceX,sourceY,sourceWidth,sourceHeight),
				GraphicsUnit.Pixel);
 
			grPhoto.Dispose();
			return bmPhoto;
		}
		static Image Crop(Image imgPhoto, int Width, int Height, AnchorPosition Anchor)
		{
			int sourceWidth = imgPhoto.Width;
			int sourceHeight = imgPhoto.Height;
			int sourceX = 0;
			int sourceY = 0;
			int destX = 0;
			int destY = 0;
 
			float nPercent = 0;
			float nPercentW = 0;
			float nPercentH = 0;
 
			nPercentW = ((float)Width/(float)sourceWidth);
			nPercentH = ((float)Height/(float)sourceHeight);
 
			if(nPercentH < nPercentW)
			{
				nPercent = nPercentW;
				switch(Anchor)
				{
					case AnchorPosition.Top:
						destY = 0;
						break;
					case AnchorPosition.Bottom:
						destY = (int)(Height - (sourceHeight * nPercent));
						break;
					default:
						destY = (int)((Height - (sourceHeight * nPercent))/2);
						break;
				}				
			}
			else
			{
				nPercent = nPercentH;
				switch(Anchor)
				{
					case AnchorPosition.Left:
						destX = 0;
						break;
					case AnchorPosition.Right:
						destX = (int)(Width - (sourceWidth * nPercent));
						break;
					default:
						destX = (int)((Width - (sourceWidth * nPercent))/2);
						break;
				}			
			}
 
			int destWidth  = (int)(sourceWidth * nPercent);
			int destHeight = (int)(sourceHeight * nPercent);
 
			Bitmap bmPhoto = new Bitmap(Width, Height, PixelFormat.Format24bppRgb);
			bmPhoto.SetResolution(imgPhoto.HorizontalResolution, imgPhoto.VerticalResolution);
 
			Graphics grPhoto = Graphics.FromImage(bmPhoto);
			grPhoto.InterpolationMode = InterpolationMode.HighQualityBicubic;
 
			grPhoto.DrawImage(imgPhoto, 
				new Rectangle(destX,destY,destWidth,destHeight),
				new Rectangle(sourceX,sourceY,sourceWidth,sourceHeight),
				GraphicsUnit.Pixel);
 
			grPhoto.Dispose();
			return bmPhoto;
		}
	}
}

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Imports System.Threading
Imports System.Data.SqlClient
Imports System.Data
Imports System.Drawing
Imports System.Drawing.Imaging
Imports System.Drawing.Drawing2D
Imports System.IO
Partial Class admin_addPhoto
    Inherits System.Web.UI.Page
    Protected savePath As String = "~/thumbnails/"
    Public Shared Function CreateResizedBitmap(ByVal inputBmp As System.Drawing.Image, ByVal sourceBmpWidth As Integer, ByVal sourceBmpHeight As Integer, ByVal newWidth As Integer, ByVal newHeight As Integer) As Bitmap
        'Adapted (but mostly copied) from http://www.codeproject.com/cs/media/bitmapmanip.asp 
        'Create a new bitmap object based on the input 
        If inputBmp Is Nothing Then
            Throw New ArgumentNullException("inputBmp")
        End If
 
        If sourceBmpWidth <= 0 Then
            sourceBmpWidth = inputBmp.Size.Width
        End If
 
        If sourceBmpHeight <= 0 Then
            sourceBmpHeight = inputBmp.Size.Height
        End If
 
        Dim xScaleFactor As Double = CSng(newWidth) / CSng(sourceBmpWidth)
        Dim yScaleFactor As Double = CSng(newHeight) / CSng(sourceBmpHeight)
 
        Dim calculatedNewWidth As Integer = CInt((sourceBmpWidth * xScaleFactor))
        Dim calculatedNewHeight As Integer = CInt((sourceBmpHeight * yScaleFactor))
 
        If calculatedNewWidth <= 0 Then
            calculatedNewWidth = 1
            ' Make sure the value is at least 1. 
            xScaleFactor = CSng(calculatedNewWidth) / CSng(sourceBmpWidth)
            ' Update the scale factor to reflect the new width 
        End If
 
        If calculatedNewHeight <= 0 Then
            calculatedNewHeight = 1
            ' Make sure the value is at least 1. 
            yScaleFactor = CSng(calculatedNewHeight) / CSng(sourceBmpHeight)
            ' Update the scale factor to reflect the new height 
        End If
 
        Dim newBmp As New Bitmap(calculatedNewWidth, calculatedNewHeight, PixelFormat.Format32bppRgb)
        'Graphics.FromImage doesn't like Indexed pixel format 
        'Create a graphics object attached to the new bitmap 
        Using newBmpGraphics As Graphics = Graphics.FromImage(newBmp)
            newBmpGraphics.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic
 
            ' Make background white. Without this a think grey line is rendered along the top and left. 
            ' See http://social.msdn.microsoft.com/Forums/en-US/winforms/thread/2c9ac8d0-366c-4919-8f92-3a91c56f41e0/ 
            newBmpGraphics.FillRectangle(Brushes.White, 0, 0, newBmp.Width, newBmp.Height)
 
            newBmpGraphics.ScaleTransform(CSng(xScaleFactor), CSng(yScaleFactor))
 
            'Draw the bitmap in the graphics object, which will apply the scale transform. 
            'Note that pixel units must be specified to ensure the framework doesn't attempt 
            'to compensate for varying horizontal resolutions in images by resizing; in this case, 
            'that's the opposite of what we want. 
            Dim drawRect As New Rectangle(0, 0, sourceBmpWidth, sourceBmpHeight)
 
            SyncLock inputBmp
                Try
                    newBmpGraphics.DrawImage(inputBmp, drawRect, drawRect, GraphicsUnit.Pixel)
                Catch generatedExceptionName As OutOfMemoryException
                    ' The garbage collector will automatically run to try to clean up memory, so let's wait for it to finish and 
                    ' try again. If it still doesn't work because the image is just too large and the system doesn't have enough 
                    ' memory, catch the OutOfMemoryException and throw one of our UnsupportedImageTypeException exceptions instead. 
                    GC.WaitForPendingFinalizers()
                    newBmpGraphics.DrawImage(inputBmp, drawRect, drawRect, GraphicsUnit.Pixel)
                End Try
            End SyncLock
        End Using
 
        Return newBmp
    End Function
    ''' <summary> 
    ''' Calculate the required width and height of a thumbnail image while preserving the 
    ''' aspect ratio of the original dimensions. If the autoEnlarge parameter is false, then preserve the original 
    ''' dimensions if they are smaller than the user-specified thumbnail dimensions. If true, then ensure that at 
    ''' least one of the out parameters (newWidth or newHeight) meets the user-specified thumbnail dimensions 
    ''' (i.e. enlarge a small image if necessary). This method does not create a thumbnail image. 
    ''' </summary> 
    ''' <param name="originalWidth">An integer specifying the width, in pixels, of the source image.</param> 
    ''' <param name="originalHeight">An integer specifying the height, in pixels, of the source image.</param> 
    ''' <param name="newWidth">An integer specifying the width, in pixels, of a thumbnail image that preserves 
    ''' the aspect ratio of the original's width and height.</param> 
    ''' <param name="newHeight">An integer specifying the height, in pixels, of a thumbnail image that preserves 
    ''' the aspect ratio of the original's width and height.</param> 
    ''' <param name="autoEnlarge">A value indicating whether to enlarge images that are smaller than the 
    ''' value specified in maxLength. If true, the new width and height will be increased if necessary 
    ''' so that at least one of the values is larger than the maxLength value. If false, the original 
    ''' width and height are returned when their dimensions are smaller than the maxLength value. This 
    ''' parameter has no effect when maxLength is greater than both originalWidth and originalHeight.</param> 
    Public Shared Sub CalculateThumbnailWidthAndHeight(ByVal originalWidth As Integer, ByVal originalHeight As Integer, ByRef newWidth As Integer, ByRef newHeight As Integer, ByVal autoEnlarge As Boolean)
        ' Maximum length of the side of the image. Applies to either width or height depending on which is longer. 
        Const maxLength As Integer = 200
 
        If Not autoEnlarge AndAlso (maxLength > originalWidth) AndAlso (maxLength > originalHeight) Then
            ' Bitmap is smaller than desired thumbnail dimensions but autoEnlarge = false. Don't enlarge thumbnail; 
            ' just use original size. 
            newWidth = originalWidth
            newHeight = originalHeight
        ElseIf originalWidth > originalHeight Then
            ' Bitmap is in landscape format (width > height). The width will be the longest dimension. 
            newWidth = maxLength
            newHeight = originalHeight * newWidth / originalWidth
        Else
            ' Bitmap is in portrait format (height > width). The height will be the longest dimension. 
            newHeight = maxLength
            newWidth = originalWidth * newHeight / originalHeight
        End If
    End Sub
    Private Shared Function resizeImage(ByVal imgToResize As Image, ByVal size As Size) As Image
        Dim sourceWidth As Integer = imgToResize.Width
        Dim sourceHeight As Integer = imgToResize.Height
 
        Dim nPercent As Single = 0
        Dim nPercentW As Single = 0
        Dim nPercentH As Single = 0
 
        nPercentW = (CSng(size.Width) / CSng(sourceWidth))
        nPercentH = (CSng(size.Height) / CSng(sourceHeight))
 
        If nPercentH < nPercentW Then
            nPercent = nPercentH
        Else
            nPercent = nPercentW
        End If
 
        Dim destWidth As Integer = CInt((sourceWidth * nPercent))
        Dim destHeight As Integer = CInt((sourceHeight * nPercent))
 
        Dim b As New Bitmap(200, 125)
        Dim g As Graphics = Graphics.FromImage(DirectCast(b, Image))
        g.InterpolationMode = InterpolationMode.HighQualityBicubic
 
        g.DrawImage(imgToResize, 0, 0, destWidth, destHeight)
        g.Dispose()
 
        Return DirectCast(b, Image)
    End Function
    Protected Sub Upload(ByVal sender As Object, ByVal e As System.EventArgs)
 
        If FileUpload1.FileName <> "" Then
            'thubnail creation and upload
            Dim fileName As String = FileUpload1.FileName
            Dim src As Bitmap = TryCast(Bitmap.FromStream(FileUpload1.PostedFile.InputStream), Bitmap)
            'Dim resultThumb As Bitmap = CreateResizedBitmap(src, src.Size.Width, src.Size.Height, 200, 150)
            Dim newWidth As Integer, newHeight As Integer
            CalculateThumbnailWidthAndHeight(src.Size.Width, src.Size.Height, newWidth, newHeight, False)
            Dim resultThumb As Bitmap = CreateResizedBitmap(src, src.Size.Width, src.Size.Height, newWidth, newHeight)
            Dim resultThumb2 As Bitmap = resizeImage(resultThumb, resultThumb.Size)
            Dim saveName As String = Server.MapPath(savePath) + fileName
            resultThumb2.Save(saveName, ImageFormat.Jpeg)

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