reduce image file size without losing quality[Answered] RSS

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  kengkit

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  103 Points

  796 Posts

  reduce image file size without losing quality

  Apr 19, 2020 08:56 AM|kengkit|LINK

  hi guys.. the following url is my reference site:
  https://www.aspdotnet-suresh.com/2011/05/how-to-resize-size-image-without-losing.html
  
  I having an issue while converting to vb using https://converter.telerik.com/
  Error Message: Type of 'image' cannot be inferred from an expression containing 'image'
  
  

      Private Sub GenerateThumbnails(ByVal scaleFactor As Double, ByVal sourcePath As Stream, ByVal targetPath As String)
          Using image = Image.FromStream(sourcePath)
              Dim newWidth = CInt((image.Width * scaleFactor))
              Dim newHeight = CInt((image.Height * scaleFactor))
              Dim thumbnailImg = New Bitmap(newWidth, newHeight)
              Dim thumbGraph = Graphics.FromImage(thumbnailImg)
              thumbGraph.CompositingQuality = CompositingQuality.HighQuality
              thumbGraph.SmoothingMode = SmoothingMode.HighQuality
              thumbGraph.InterpolationMode = InterpolationMode.HighQualityBicubic
              Dim imageRectangle = New Rectangle(0, 0, newWidth, newHeight)
              thumbGraph.DrawImage(image, imageRectangle)
              thumbnailImg.Save(targetPath, image.RawFormat)
          End Using
      End Sub

  
  
  
  

• • Reply
  mbanavige

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  Re: reduce image file size without losing quality

  Apr 19, 2020 10:54 AM|mbanavige|LINK

  I can't see if you imported the Sytem.Drawing namespace.  Could just fully qualify the name.

  Using image As System.Drawing.Image = System.Drawing.Image.FromStream(sourcePath)

  Mike Banavige
• • Reply
  samwu

  Contributor

  3370 Points

  1409 Posts

  Re: reduce image file size without losing quality

  Apr 20, 2020 02:03 AM|samwu|LINK

  Hi kengkit,

  kengkit

  Using image = Image.FromStream(sourcePath)

  As mbanavige said, you should fully qualify the name.

  The C # code in the link you provided is problematic, It should be the following code, and then you will convert it to vb code.

  C#:
  var image = System.Drawing.Image.FromStream(sourcePath)
  
  VB:
  Dim image = System.Drawing.Image.FromStream(sourcePath)

  More information about Image.FromStream Method you can refer to this link:

  https://docs.microsoft.com/en-us/dotnet/api/system.drawing.image.fromstream?view=netframework-4.8

  Best regards,

  Sam

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