Spire.Doc 是一款專門對 Word 文檔進行操作的 類庫。在于幫助開發人員無需安裝 Microsoft Word情況下，輕松快捷高效地創建、編輯、轉換和打印 Microsoft Word 文檔。擁有近10年專業開發經驗Spire系列辦公文檔開發工具，專注于創建、編輯、轉換和打印Word/PDF/Excel等格式文件處理，小巧便捷。 

E-iceblue 功能類庫Spire 系列文檔處理組件均由中國本土團隊研發，不依賴第三方軟件，不受其他國家的技術或法律法規限制，同時適配國產操作系統如中科方德、中標麒麟等，兼容國產文檔處理軟件 WPS（如 .wps/.et/.dps 等格式

Spire.PDF for.net下載   Spire.PDF for java下載

Tiff圖像作為圖形容器，可以存儲光柵圖像和矢量圖像；可能包含支持 1 至 24 位顏色深度的高質量圖形；支持有損和無損壓縮；還支持多層和頁面。如果您希望文檔能夠轉換為高質量的圖形，并且在壓縮過程中保存時不丟失圖像文件信息，tiff 圖像是您的最佳選擇。

本文介紹了使用Spire.PDF for .NET 通過 document.SaveAsImage() 和 JoinTiffImages() 方法將 PDF 文檔保存為 tiff 圖像的詳細方法，Spire.PDF for .NET是一個 PDF 組件，包含令人難以置信的豐富的創建、閱讀、編輯功能并在.NET、Silverlight 和 WPF 平臺上操作 PDF 文檔。下面的屏幕截圖顯示了將 PDF 文檔保存為 tiff 圖像后的結果：

該方法的主要步驟是：

第 1 步：創建一個新的 pdf 文檔并加載它。

PdfDocument document = new PdfDocument();
document.LoadFromFile(@"sample.pdf");

步驟2： 使用document.SaveAsImage()方法將pdf文檔保存為圖像數組。

private static Image[] SaveAsImage(PdfDocument document)
{
Image[] images = new Image[document.Pages.Count];
for (int i = 0; i < document.Pages.Count; i++)
{
//use the document.SaveAsImage() method save the pdf as image
images[i] = document.SaveAsImage(i);
}
return images;
}

步驟 3：使用 JoinTiffImages() 方法將 pdf 頁面中的圖像保存為 tiff 圖像類型，并指定編碼器和圖像編碼器參數。

public static void JoinTiffImages(Image[] images, string outFile, EncoderValue compressEncoder)
{
//use the save encoder
Encoder enc = Encoder.SaveFlag;
EncoderParameters ep = new EncoderParameters(2);
ep.Param[0] = new EncoderParameter(enc, (long)EncoderValue.MultiFrame);
ep.Param[1] = new EncoderParameter(Encoder.Compression, (long)compressEncoder);
Image pages = images[0];
int frame = 0;
ImageCodecInfo info = GetEncoderInfo("image/tiff");
foreach (Image img in images)
{
if (frame == 0)
{
pages = img;
//save the first frame
pages.Save(outFile, info, ep);
}
else
{
//save the intermediate frames
ep.Param[0] = new EncoderParameter(enc, (long)EncoderValue.FrameDimensionPage);
pages.SaveAdd(img, ep);
}
if (frame == images.Length - 1)
{
//flush and close.
ep.Param[0] = new EncoderParameter(enc, (long)EncoderValue.Flush);
pages.SaveAdd(ep);
}
frame++;
}
}

完整代碼：

[C＃]

using System;
using System.Drawing;
using System.Drawing.Imaging;
using Spire.Pdf;
namespace SavePdfAsTiff
{
class Program
{
static void Main(string[] args)
{
PdfDocument document = new PdfDocument();
document.LoadFromFile(@"01.pdf");
JoinTiffImages(SaveAsImage(document),"result.tiff",EncoderValue.CompressionLZW);
System.Diagnostics.Process.Start("result.tiff");
}
private static Image[] SaveAsImage(PdfDocument document)
{
Image[] images = new Image[document.Pages.Count];
for (int i = 0; i < document.Pages.Count; i++)
{
images[i] = document.SaveAsImage(i);
}
return images;
}

private static ImageCodecInfo GetEncoderInfo(string mimeType)
{
ImageCodecInfo[] encoders = ImageCodecInfo.GetImageEncoders();
for (int j = 0; j < encoders.Length; j++)
{
if (encoders[j].MimeType == mimeType)
return encoders[j];
}
throw new Exception(mimeType + " mime type not found in ImageCodecInfo");
}

public static void JoinTiffImages(Image[] images, string outFile, EncoderValue compressEncoder)
{
//use the save encoder
Encoder enc = Encoder.SaveFlag;
EncoderParameters ep = new EncoderParameters(2);
ep.Param[0] = new EncoderParameter(enc, (long)EncoderValue.MultiFrame);
ep.Param[1] = new EncoderParameter(Encoder.Compression, (long)compressEncoder);
Image pages = images[0];
int frame = 0;
ImageCodecInfo info = GetEncoderInfo("image/tiff");
foreach (Image img in images)
{
if (frame == 0)
{
pages = img;
//save the first frame
pages.Save(outFile, info, ep);
}

else
{
//save the intermediate frames
ep.Param[0] = new EncoderParameter(enc, (long)EncoderValue.FrameDimensionPage);

pages.SaveAdd(img, ep);
}
if (frame == images.Length - 1)
{
//flush and close.
ep.Param[0] = new EncoderParameter(enc, (long)EncoderValue.Flush);
pages.SaveAdd(ep);
}
frame++;
}
}
}
}

[VB.NET]

Imports System
Imports System.Drawing
Imports System.Drawing.Imaging
Imports Spire.Pdf
Namespace SavePdfAsTiff
Class Program
Sub Main()
Dim document As PdfDocument = New PdfDocument()
document.LoadFromFile("01.pdf")
JoinTiffImages(SaveAsImage(document), "result.tiff", EncoderValue.CompressionLZW)
System.Diagnostics.Process.Start("result.tiff")
End Sub
Private Shared Function SaveAsImage(ByVal document As PdfDocument)
Dim images() As Image = New Image(document.Pages.Count-1) {}
Dim i As Integer
For i = 0 To document.Pages.Count - 1 Step i + 1
images(i) = document.SaveAsImage(i)
Next
Return images
End Function
Private Shared Function GetEncoderInfo(ByVal mimeType As String) As ImageCodecInfo
Dim encoders() As ImageCodecInfo = ImageCodecInfo.GetImageEncoders()
Dim j As Integer
For j = 0 To encoders.Length - 1 Step j + 1
If encoders(j).MimeType = mimeType Then
Return encoders(j)
End If
Next
Throw New Exception(mimeType + " mime type not found in ImageCodecInfo")
End Function
Public Shared Sub JoinTiffImages(ByVal images() As Image, ByVal outFile As String, ByVal compressEncoder As EncoderValue)
'use the save encoder
Dim enc As Encoder = Encoder.SaveFlag
Dim ep As EncoderParameters = New EncoderParameters(2)
ep.Param(0) = New EncoderParameter(enc, CType(EncoderValue.MultiFrame, Long))
ep.Param(1) = New EncoderParameter(Encoder.Compression, CType(compressEncoder, Long))
Dim pages As Image = images(0)
Dim frame As Integer = 0
Dim info As ImageCodecInfo = GetEncoderInfo("image/tiff")
Dim img As Image
For Each img In images
If frame = 0 Then
pages = img
'save the first frame
pages.Save(outFile, info, ep)
Else
'save the intermediate frames
ep.Param(0) = New EncoderParameter(enc, CType(EncoderValue.FrameDimensionPage, Long))
pages.SaveAdd(img, ep)
End If

If frame = images.Length - 1 Then
'flush and close.
ep.Param(0) = New EncoderParameter(enc, CType(EncoderValue.Flush, Long))
pages.SaveAdd(ep)
End If
frame = frame + 1
Next
End Sub
End Class
End Namespace

以上便是如何PDF 文檔另存為 tiff 圖像，如果您有其他問題也可以繼續瀏覽本系列文章，獲取相關教程，你還可以給我留言或者加入我們的官方技術交流群。

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