reduce image file size without losing quality

Question

User944339287 posted

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

Answer 1

User-158764254 posted

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)

Answer 2

User288213138 posted

Hi 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