Encoder.SaveFlag 字段

定义

命名空间:

System.Drawing.Imaging

程序集:

System.Drawing.Common.dll

包:

System.Drawing.Common v8.0.0

Source:

Encoder.cs

表示用保存标志参数类别的全局唯一标识符初始化的 Encoder 对象。

public: static initonly System::Drawing::Imaging::Encoder ^ SaveFlag;

public static readonly System.Drawing.Imaging.Encoder SaveFlag;

 staticval mutable SaveFlag : System.Drawing.Imaging.Encoder

Public Shared ReadOnly SaveFlag As Encoder 

字段值

Encoder

示例

以下示例创建三 Bitmap 个对象：一个来自 BMP 文件，一个来自 JPEG 文件，一个来自 PNG 文件。 该代码将所有三个图像保存在一个多帧 TIFF 文件中。

#using <System.Drawing.dll>

using namespace System;
using namespace System::Drawing;
using namespace System::Drawing::Imaging;
static ImageCodecInfo^ GetEncoderInfo( String^ mimeType );
int main()
{
   Bitmap^ multi;
   Bitmap^ page2;
   Bitmap^ page3;
   ImageCodecInfo^ myImageCodecInfo;
   Encoder^ myEncoder;
   EncoderParameter^ myEncoderParameter;
   EncoderParameters^ myEncoderParameters;
   
   // Create three Bitmap objects.
   multi = gcnew Bitmap( "Shapes.bmp" );
   page2 = gcnew Bitmap( "Iron.jpg" );
   page3 = gcnew Bitmap( "House.png" );
   
   // Get an ImageCodecInfo object that represents the TIFF codec.
   myImageCodecInfo = GetEncoderInfo( "image/tiff" );
   
   // Create an Encoder object based on the GUID
   // for the SaveFlag parameter category.
   myEncoder = Encoder::SaveFlag;
   
   // 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 first page (frame).
   myEncoderParameter = gcnew EncoderParameter( myEncoder,(__int64)EncoderValue::MultiFrame );
   myEncoderParameters->Param[ 0 ] = myEncoderParameter;
   multi->Save( "Multiframe.tiff", myImageCodecInfo, myEncoderParameters );
   
   // Save the second page (frame).
   myEncoderParameter = gcnew EncoderParameter( myEncoder,(__int64)EncoderValue::FrameDimensionPage );
   myEncoderParameters->Param[ 0 ] = myEncoderParameter;
   multi->SaveAdd( page2, myEncoderParameters );
   
   // Save the third page (frame).
   myEncoderParameter = gcnew EncoderParameter( myEncoder,(__int64)EncoderValue::FrameDimensionPage );
   myEncoderParameters->Param[ 0 ] = myEncoderParameter;
   multi->SaveAdd( page3, myEncoderParameters );
   
   // Close the multiple-frame file.
   myEncoderParameter = gcnew EncoderParameter( myEncoder,(__int64)EncoderValue::Flush );
   myEncoderParameters->Param[ 0 ] = myEncoderParameter;
   multi->SaveAdd( 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_MultiFrame
{
    public static void Main()
    {
        Bitmap multi;
        Bitmap page2;
        Bitmap page3;
        ImageCodecInfo myImageCodecInfo;
        Encoder myEncoder;
        EncoderParameter myEncoderParameter;
        EncoderParameters myEncoderParameters;
                     
        // Create three Bitmap objects.
        multi = new Bitmap("Shapes.bmp");
        page2 = new Bitmap("Iron.jpg");
        page3 = new Bitmap("House.png");
                     
        // Get an ImageCodecInfo object that represents the TIFF codec.
        myImageCodecInfo = GetEncoderInfo("image/tiff");
                     
        // Create an Encoder object based on the GUID
        // for the SaveFlag parameter category.
        myEncoder = Encoder.SaveFlag;
                     
        // 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 first page (frame).
        myEncoderParameter = new EncoderParameter(
            myEncoder,
            (long)EncoderValue.MultiFrame);
        myEncoderParameters.Param[0] = myEncoderParameter;
        multi.Save("Multiframe.tiff", myImageCodecInfo, myEncoderParameters);
                     
        // Save the second page (frame).
        myEncoderParameter = new EncoderParameter(
            myEncoder,
            (long)EncoderValue.FrameDimensionPage);
        myEncoderParameters.Param[0] = myEncoderParameter;
        multi.SaveAdd(page2, myEncoderParameters);
                     
        // Save the third page (frame).
        myEncoderParameter = new EncoderParameter(
            myEncoder,
            (long)EncoderValue.FrameDimensionPage);
        myEncoderParameters.Param[0] = myEncoderParameter;
        multi.SaveAdd(page3, myEncoderParameters);
                     
        // Close the multiple-frame file.
        myEncoderParameter = new EncoderParameter(
            myEncoder,
            (long)EncoderValue.Flush);
        myEncoderParameters.Param[0] = myEncoderParameter;
        multi.SaveAdd(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_MultiFrame
    
    Public Shared Sub Main() 
        Dim multi As Bitmap
        Dim page2 As Bitmap
        Dim page3 As Bitmap
        Dim myImageCodecInfo As ImageCodecInfo
        Dim myEncoder As Encoder
        Dim myEncoderParameter As EncoderParameter
        Dim myEncoderParameters As EncoderParameters
        
        ' Create three Bitmap objects.
        multi = New Bitmap("Shapes.bmp")
        page2 = New Bitmap("Iron.jpg")
        page3 = New Bitmap("House.png")
        
        ' Get an ImageCodecInfo object that represents the TIFF codec.
        myImageCodecInfo = GetEncoderInfo("image/tiff")
        
        ' Create an Encoder object based on the GUID
        ' for the SaveFlag parameter category.
        myEncoder = Encoder.SaveFlag
        
        ' 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 first page (frame).
        myEncoderParameter = New EncoderParameter(myEncoder, Fix(EncoderValue.MultiFrame))
        myEncoderParameters.Param(0) = myEncoderParameter
        multi.Save("Multiframe.tiff", myImageCodecInfo, myEncoderParameters)
        
        ' Save the second page (frame).
        myEncoderParameter = New EncoderParameter(myEncoder, Fix(EncoderValue.FrameDimensionPage))
        myEncoderParameters.Param(0) = myEncoderParameter
        multi.SaveAdd(page2, myEncoderParameters)
        
        ' Save the third page (frame).
        myEncoderParameter = New EncoderParameter(myEncoder, Fix(EncoderValue.FrameDimensionPage))
        myEncoderParameters.Param(0) = myEncoderParameter
        multi.SaveAdd(page3, myEncoderParameters)
        
        ' Close the multiple-frame file.
        myEncoderParameter = New EncoderParameter(myEncoder, Fix(EncoderValue.Flush))
        myEncoderParameters.Param(0) = myEncoderParameter
        multi.SaveAdd(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 'GetEncoderInfo
End Class

注解

将参数传递给图像编码器时，参数将封装在 对象中 EncoderParameter 。 对象的字段之 EncoderParameter 一是指定参数类别的 GUID。 使用 类的 Encoder 静态字段检索 Encoder 包含所需类别参数的 。

内置于 GDI+ 中的图像编码器接收属于多个类别的参数。 下表列出了所有类别以及与每个类别关联的 GUID。

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

另请参阅

• 在托管 GDI+ 中使用图像编码器和解码器