PDF控件Spire.PDF for .NET【转换】演示：将PDF 文档另存为 tiff 图像

╰+哭是因爲堅強的太久メ 2023-10-14 16:36 5阅读 0赞

[Spire.Doc ][Spire.Doc]是一款专门对 Word 文档进行操作的 类库。在于帮助开发人员无需安装 Microsoft Word情况下，轻松快捷高效地创建、编辑、转换和打印 Microsoft Word 文档。拥有近10年专业开发经验Spire系列办公文档开发工具，专注于创建、编辑、转换和打印Word/PDF/Excel等格式文件处理，小巧便捷。

[E-iceblue ][E-iceblue]功能类库Spire 系列文档处理组件均由中国本土团队研发，不依赖第三方软件，不受其他国家的技术或法律法规限制，同时适配国产操作系统如中科方德、中标麒麟等，兼容国产文档处理软件 WPS（如 .wps/.et/.dps 等格式

Tiff图像作为图形容器，可以存储光栅图像和矢量图像；可能包含支持 1 至 24 位颜色深度的高质量图形；支持有损和无损压缩；还支持多层和页面。如果您希望文档能够转换为高质量的图形，并且在压缩过程中保存时不丢失图像文件信息，tiff 图像是您的最佳选择。

本文介绍了使用[Spire.PDF for .NET ][Spire.Doc]通过 document.SaveAsImage() 和 JoinTiffImages() 方法将 PDF 文档保存为 tiff 图像的详细方法，Spire.PDF for .NET是一个 PDF 组件，包含令人难以置信的丰富的创建、阅读、编辑功能并在.NET、Silverlight 和 WPF 平台上操作 PDF 文档。下面的屏幕截图显示了将 PDF 文档保存为 tiff 图像后的结果：

![将 PDF 文档另存为 tiff 图像][PDF _ tiff]

该方法的主要步骤是：

**第 1 步：**创建一个新的 pdf 文档并加载它。

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

**步骤2：** 使用document.SaveAsImage()方法将pdf文档保存为图像数组。

>     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;
>     }

**步骤 3**：使用 JoinTiffImages() 方法将 pdf 页面中的图像保存为 tiff 图像类型，并指定编码器和图像编码器参数。

>     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++;
>     }
>     }

**完整代码：**

**\[C＃\]**

>     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 文档另存为 tiff 图像，如果您有其他问题也可以继续浏览本系列文章，获取相关教程~

[Spire.Doc]: https://www.evget.com/product/3368/download
[E-iceblue]: https://www.evget.com/vendor/481
[PDF _ tiff]: https://img-blog.csdnimg.cn/img_convert/ac959f26b34416d508239366e84f598d.png