主题：图片压缩

mark 压缩图片

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