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EncoderParameter Class

Used to pass a value, or an array of values, to an image encoder.

Namespace:  System.Drawing.Imaging
Assembly:  System.Drawing (in System.Drawing.dll)

'Declaration
Public NotInheritable Class EncoderParameter _
	Implements IDisposable
'Usage
Dim instance As EncoderParameter

You can also use an EncoderParameter object to receive a list of possible values supported by a particular parameter of a particular image encoder.

The following code example demonstrates how to create a EncoderParameter using the EncoderParameter constructor. To run this example, paste the code into a Windows Form and call the VaryQualityLevel method from the form's constructor. This example requires an image file named TestPhoto.jpg located at c:\.

Private Sub VaryQualityLevel()
    ' Get a bitmap.
    Dim bmp1 As New Bitmap("c:\TestPhoto.jpg")
    Dim jgpEncoder As ImageCodecInfo = GetEncoder(ImageFormat.Jpeg)

    ' Create an Encoder object based on the GUID
    ' for the Quality parameter category.
    Dim myEncoder As System.Drawing.Imaging.Encoder = System.Drawing.Imaging.Encoder.Quality

    ' Create an EncoderParameters object.
    ' An EncoderParameters object has an array of EncoderParameter
    ' objects. In this case, there is only one
    ' EncoderParameter object in the array.
    Dim myEncoderParameters As New EncoderParameters(1)

    Dim myEncoderParameter As New EncoderParameter(myEncoder, 50&)
    myEncoderParameters.Param(0) = myEncoderParameter
    bmp1.Save("c:\TestPhotoQualityFifty.jpg", jgpEncoder, myEncoderParameters)

    myEncoderParameter = New EncoderParameter(myEncoder, 100&)
    myEncoderParameters.Param(0) = myEncoderParameter
    bmp1.Save("c:\TestPhotoQualityHundred.jpg", jgpEncoder, myEncoderParameters)

    ' Save the bitmap as a JPG file with zero quality level compression.
    myEncoderParameter = New EncoderParameter(myEncoder, 0&)
    myEncoderParameters.Param(0) = myEncoderParameter
    bmp1.Save("c:\TestPhotoQualityZero.jpg", jgpEncoder, myEncoderParameters)

End Sub 'VaryQualityLevel



...


Private Function GetEncoder(ByVal format As ImageFormat) As ImageCodecInfo

    Dim codecs As ImageCodecInfo() = ImageCodecInfo.GetImageDecoders()

    Dim codec As ImageCodecInfo
    For Each codec In codecs
        If codec.FormatID = format.Guid Then
            Return codec
        End If
    Next codec
    Return Nothing

End Function

System.Object
  System.Drawing.Imaging.EncoderParameter

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0, 2.0, 1.1, 1.0

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