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• Download source - 2.74 KB

Introduction

Batch Image Resizer resizes all the selected images to a particular size as specified in the textbox. To resize several images at once, just drag and drop the files to the left box (Left box accepts only image files), specify the height and width to which you want to resize them and click on the resize button. Then, it will show all the resized images in the right box. Images checked in the right box are resized successfully and images that are unchecked are not successfully resized due to some error.

Using the Code

Given below is the main source code...

The below subroutine resizes images of different formats, and keeps their format as it is.

Private Sub BatchImageResizerfun(ByVal strr As String)

        Dim bm As New Bitmap(strr)
        Dim i As Integer

        Dim str11 As String = Mid(strr, Len(strr) - 2, 3) 'Stores the format 
						'of the image i.e. png, jpg

        Dim bmname As String = ""
        Dim c As Char = Nothing

        For i = 4 To Len(strr) 'stores  filename
            c = Mid(strr, Len(strr) - i, 1)
            If c = Char.Parse("\") Then
                Exit For
            End If
            bmname = bmname + c
        Next

        bmname = mypicturefolder & "\" & StrReverse(bmname)

        Dim width As Integer = Integer.Parse(TextBox2.Text)	'image width.
        Dim height As Integer = Integer.Parse(TextBox1.Text)	'image height

        Dim thumb As New Bitmap(width, height)
        Dim g As Graphics = Graphics.FromImage(thumb)

        g.InterpolationMode = Drawing2D.InterpolationMode.HighQualityBicubic
        g.DrawImage(bm, New Rectangle(0, 0, width, height), _
		New Rectangle(0, 0, bm.Width, bm.Height), GraphicsUnit.Pixel)
        g.Dispose()

        Try
            Select Case Strings.LCase(str11) 'saves the file to their 
					'corresponding format after resize
                Case ""
                    Exit Sub
                Case "bmp"
                    thumb.Save(bmname & ".bmp", Imaging.ImageFormat.Bmp)
                Case "jpg"
                    thumb.Save(bmname & ".jpg", Imaging.ImageFormat.Jpeg)
                Case "gif"
                    thumb.Save(bmname & ".gif", Imaging.ImageFormat.Gif)
                Case "ico"
                    thumb.Save(bmname & ".ico", Imaging.ImageFormat.Icon)
                Case "png"
                    thumb.Save(bmname & ".png", Imaging.ImageFormat.Png)
                Case "tiff"
                    thumb.Save(bmname & ".tiff", Imaging.ImageFormat.Tiff)
                Case "wmf"
                    thumb.Save(bmname & ".wmf", Imaging.ImageFormat.Wmf)
            End Select
            CheckedListBox1.Items.Add(bmname & "." & str11, True) 'file resized 
							'successfully
        Catch ex As Exception
            CheckedListBox1.Items.Add(bmname & "." & str11, False) 'file resizing 
							'unsuccessful
        End Try

        bm.Dispose()
        thumb.Dispose()

    End Sub

When images are dropped to the left box from the explorer, it checks for the following:

1. It is an image file or not. If not, then don't add to the list.
2. If the image file is already added to the list, then don't add it again.
   To remove pictures from being resized, select the file and right click to remove from the list.

To resize pictures, specify width and height to be resized, and then click on resize button. It resizes pictures and opens the directory where the pictures have been stored.

The below image shows how it works: