专家坐堂-【已解决】[求助]如何将图片转换为黑白的、如何将图片压缩指定大小Foxtable(狐表) - 新一代数据库软件，完美融合Access、Foxpro、Excel、vb.net之优势，人人都能掌握的快速软件开发工具!

Dim file As String = "C:\\测试.jpg"

Dim img As image = getImage(file)

Dim bmp As bitmap

If img.width > 80 Then

If 80 * (img.height / img.width) > 60 Then

bmp = new bitmap(img, 80*(60/(80*(img.height/img.width))), 60)

Else

bmp = new bitmap(img, 80, 80 * (img.height / img.width))

End If

bmp.save("C:\\缩略图.jpg")

bmp.Dispose

质量保存

Dim img As image = getimage("g:\\aaa.jpg")
Dim bmp As new bitmap(img.width, img.height)
Dim g = graphics.fromimage(bmp)
g.DrawImage(img, 0, 0, img.Width, img.Height)
Dim jpgEncoder As ImageCodecInfo
Dim codecs() As ImageCodecInfo = ImageCodecInfo.GetImageDecoders
For Each codec As ImageCodecInfo In codecs
    If (codec.FormatID = ImageFormat.Jpeg.Guid) Then
        jpgEncoder = codec
        Exit For
    End If
Next
Dim myEncoder As System.Drawing.Imaging.Encoder = System.Drawing.Imaging.Encoder.Quality
Dim myEncoderParameters As EncoderParameters = New EncoderParameters(1)
Dim myEncoderParameter As EncoderParameter = New EncoderParameter(myEncoder, 30) \' 质量级别 0 对应于最大压缩，而质量级别 100 对应于最小压缩
myEncoderParameters.Param(0) = myEncoderParameter

bmp.Save("g:\\压缩图aaa.jpg", jpgEncoder, myEncoderParameters)
bmp.dispose

g.dispose

图片黑白

Dim dlg As New OpenFileDialog \'定义一个新的OpenFileDialog

dlg.Filter = "图片文件|*.jpg;*.png" \'设置筛选器

If dlg.ShowDialog = DialogResult.OK Then \'如果用户单击了确定按钮

Dim omg As Image = GetImage(dlg.FileName)

Windows.Forms.ControlPaint.DrawImageDisabled(Graphics.FromImage(omg), omg, 0, 0, Color.Transparent)

Forms("窗口1").Controls("PictureBox1").Image = omg

End If