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Encoder.ColorDepth Field

Definition

An Encoder object that is initialized with the globally unique identifier for the color depth parameter category.

public: static initonly System::Drawing::Imaging::Encoder ^ ColorDepth;
public static readonly System.Drawing.Imaging.Encoder ColorDepth;
 staticval mutable ColorDepth : System.Drawing.Imaging.Encoder
Public Shared ReadOnly ColorDepth As Encoder 

Field Value

Examples

The following example creates a Bitmap object from a BMP file. The code saves the image as a TIFF file that has a color depth of 24 bits per pixel.

#using <System.Drawing.dll>

using namespace System;
using namespace System::Drawing;
using namespace System::Drawing::Imaging;
static ImageCodecInfo^ GetEncoderInfo( String^ mimeType );
int main()
{
   Bitmap^ myBitmap;
   ImageCodecInfo^ myImageCodecInfo;
   Encoder^ myEncoder;
   EncoderParameter^ myEncoderParameter;
   EncoderParameters^ myEncoderParameters;
   
   // Create a Bitmap object based on a BMP file.
   myBitmap = gcnew Bitmap( "C:\\Documents and Settings\\All Users\\Documents\\My Music\\music.bmp" );
   
   // Get an ImageCodecInfo object that represents the TIFF codec.
   myImageCodecInfo = GetEncoderInfo( "image/tiff" );
   
   // Create an Encoder object based on the GUID
   // for the ColorDepth parameter category.
   myEncoder = Encoder::ColorDepth;
   
   // 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.
   myEncoderParameters = gcnew EncoderParameters( 1 );
   
   // Save the image with a color depth of 24 bits per pixel.
   myEncoderParameter = gcnew EncoderParameter( myEncoder,__int64(24) );
   myEncoderParameters->Param[ 0 ] = myEncoderParameter;
   myBitmap->Save( "Shapes24bpp.tiff", myImageCodecInfo, myEncoderParameters );
}

static ImageCodecInfo^ GetEncoderInfo( String^ mimeType )
{
   int j;
   array<ImageCodecInfo^>^encoders;
   encoders = ImageCodecInfo::GetImageEncoders();
   for ( j = 0; j < encoders->Length; ++j )
   {
      if ( encoders[ j ]->MimeType == mimeType )
            return encoders[ j ];

   }
   return nullptr;
}
using System;
using System.Drawing;
using System.Drawing.Imaging;
class Example_SetColorDepth
{
    public static void Main()
    {
        Bitmap myBitmap;
        ImageCodecInfo myImageCodecInfo;
        Encoder myEncoder;
        EncoderParameter myEncoderParameter;
        EncoderParameters myEncoderParameters;
                     
        // Create a Bitmap object based on a BMP file.
        myBitmap = new Bitmap(@"C:\Documents and Settings\All Users\Documents\My Music\music.bmp");
                     
        // Get an ImageCodecInfo object that represents the TIFF codec.
        myImageCodecInfo = GetEncoderInfo("image/tiff");
                     
        // Create an Encoder object based on the GUID
        // for the ColorDepth parameter category.
        myEncoder = Encoder.ColorDepth;
                     
        // 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.
        myEncoderParameters = new EncoderParameters(1);
                     
        // Save the image with a color depth of 24 bits per pixel.
        myEncoderParameter =
            new EncoderParameter(myEncoder, 24L);
        myEncoderParameters.Param[0] = myEncoderParameter;
        myBitmap.Save("Shapes24bpp.tiff", myImageCodecInfo, myEncoderParameters);
    }

    private static ImageCodecInfo GetEncoderInfo(String mimeType)
    {
        int j;
        ImageCodecInfo[] encoders;
        encoders = ImageCodecInfo.GetImageEncoders();
        for(j = 0; j < encoders.Length; ++j)
        {
            if(encoders[j].MimeType == mimeType)
                return encoders[j];
        }
        return null;
    }
}
Imports System.Drawing
Imports System.Drawing.Imaging

Class Example_SetColorDepth

    Public Shared Sub Main()
        Dim myBitmap As Bitmap
        Dim myImageCodecInfo As ImageCodecInfo
        Dim myEncoder As Encoder
        Dim myEncoderParameter As EncoderParameter
        Dim myEncoderParameters As EncoderParameters

        ' Create a Bitmap object based on a BMP file.
        myBitmap = New Bitmap("C:\Documents and Settings\All Users\Documents\My Music\music.bmp")

        ' Get an ImageCodecInfo object that represents the TIFF codec.
        myImageCodecInfo = GetEncoderInfo("image/tiff")

        ' Create an Encoder object based on the GUID
        ' for the ColorDepth parameter category.
        myEncoder = Encoder.ColorDepth

        ' 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.
        myEncoderParameters = New EncoderParameters(1)

        ' Save the image with a color depth of 24 bits per pixel.
        myEncoderParameter = New EncoderParameter(myEncoder, CType(24L, Int32))
        myEncoderParameters.Param(0) = myEncoderParameter
        myBitmap.Save("Shapes24bpp.tiff", myImageCodecInfo, myEncoderParameters)

    End Sub


    Private Shared Function GetEncoderInfo(ByVal mimeType As String) As ImageCodecInfo
        Dim j As Integer
        Dim encoders() As ImageCodecInfo
        encoders = ImageCodecInfo.GetImageEncoders()

        j = 0
        While j < encoders.Length
            If encoders(j).MimeType = mimeType Then
                Return encoders(j)
            End If
            j += 1
        End While
        Return Nothing

    End Function
End Class

Remarks

When you pass a parameter to an image encoder, the parameter is encapsulated in an EncoderParameter object. One of the fields of the EncoderParameter object is a GUID that specifies the category of the parameter. Use the static fields of the Encoder class to retrieve an Encoder that contains parameters of the desired category.

The image encoders that are built into GDI+ receive parameters that belong to several categories. The following table lists all the categories and the GUID associated with each category.

ChrominanceTable f2e455dc-09b3-4316-8260-676ada32481c

ColorDepth 66087055-ad66-4c7c-9a18-38a2310b8337

Compression e09d739d-ccd4-44ee-8eba-3fbf8be4fc58

LuminanceTable edb33bce-0266-4a77-b904-27216099e717

Quality 1d5be4b5-fa4a-452d-9cdd-5db35105e7eb

RenderMethod 6d42c53a-229a-4825-8bb7-5c99e2b9a8b8

SaveFlag 292266fc-ac40-47bf-8cfc-a85b89a655de

ScanMethod 3a4e2661-3109-4e56-8536-42c156e7dcfa

Transformation 8d0eb2d1-a58e-4ea8-aa14-108074b7b6f9

Version 24d18c76-814a-41a4-bf53-1c219cccf797

Applies to

See also