从演示文稿形状中提取图像

图像通常被添加到形状中，并且也经常用作幻灯片的背景。图像对象是通过 IImageCollection 添加的，这是一个 IPPImage 对象的集合。

本文解释了如何从演示文稿中提取添加的图像。

要从演示文稿中提取图像，您首先需要通过遍历每个幻灯片并逐一检查每个形状来找到图像。一旦找到或识别出图像，您可以提取它并将其保存为新文件。 XXX

public static void Run() {

    String path = @"D:\Aspose Data\";
    // 访问演示文稿
    Presentation pres = new Presentation(path + "ExtractImages.pptx");
    Aspose.Slides.IPPImage img = null;
    Aspose.Slides.IPPImage Backimg = null;

    int slideIndex = 0;
    String ImageType = "";
    bool ifImageFound = false;
    for (int i = 0; i < pres.Slides.Count; i++)
    {

        slideIndex++;
        // 访问第一张幻灯片
        ISlide sl = pres.Slides[i];
        System.Drawing.Imaging.ImageFormat Format = System.Drawing.Imaging.ImageFormat.Jpeg;

        // 访问第一张幻灯片 Slide sl = pres.getSlideByPosition(i);
        if (sl.Background.FillFormat.FillType == FillType.Picture)
        {
            // 获取背景图像  
            Backimg = sl.Background.FillFormat.PictureFillFormat.Picture.Image;

            // 设置首选图像格式 

            ImageType = Backimg.ContentType;
            ImageType = ImageType.Remove(0, ImageType.IndexOf("/") + 1);
            Format = GetImageFormat(ImageType);

            String ImagePath = path + "BackImage_";
            Backimg.SystemImage.Save(ImagePath + "Slide_" + slideIndex.ToString() + "." + ImageType, Format);

        }
        else
        {
            if (sl.LayoutSlide.Background.FillFormat.FillType == FillType.Picture)
            {
                // 获取背景图像  
                Backimg = sl.LayoutSlide.Background.FillFormat.PictureFillFormat.Picture.Image;

                // 设置首选图像格式 

                ImageType = Backimg.ContentType;
                ImageType = ImageType.Remove(0, ImageType.IndexOf("/") + 1);
                Format = GetImageFormat(ImageType);

                String ImagePath = path + "BackImage_Slide_" + i;
                Backimg.SystemImage.Save(ImagePath + "LayoutSlide_" + slideIndex.ToString() + "." + ImageType, Format);

            }
        }

        for (int j = 0; j < sl.Shapes.Count; j++)
        {
            // 访问包含图像的形状
            IShape sh = sl.Shapes[j];

            if (sh is AutoShape)
            {
                AutoShape ashp = (AutoShape)sh;
                if (ashp.FillFormat.FillType == FillType.Picture)
                {
                    img = ashp.FillFormat.PictureFillFormat.Picture.Image;
                    ImageType = img.ContentType;
                    ImageType = ImageType.Remove(0, ImageType.IndexOf("/") + 1);
                    ifImageFound = true;

                }
            }

            else if (sh is PictureFrame)
            {
                IPictureFrame pf = (IPictureFrame)sh;
                if (pf.FillFormat.FillType == FillType.Picture)
                {
                    img = pf.PictureFormat.Picture.Image;
                    ImageType = img.ContentType;
                    ImageType = ImageType.Remove(0, ImageType.IndexOf("/") + 1);
                    ifImageFound = true;
                }
            }

            // 设置提取图像的首选格式
            if (ifImageFound)
            {
                Format = GetImageFormat(ImageType);
                String ImagePath = path + "Slides\\Image_";
                img.SystemImage.Save(ImagePath + "Slide_" + slideIndex.ToString() + "_Shape_" + j.ToString() + "." + ImageType, Format);
            }
            ifImageFound = false;
        }
    }
}

public static System.Drawing.Imaging.ImageFormat GetImageFormat(String ImageType)
{
    System.Drawing.Imaging.ImageFormat Format = System.Drawing.Imaging.ImageFormat.Jpeg;
    switch (ImageType)
    {
        case "jpeg":
            Format = System.Drawing.Imaging.ImageFormat.Jpeg;
            break;

        case "emf":
            Format = System.Drawing.Imaging.ImageFormat.Emf;
            break;

        case "bmp":
            Format = System.Drawing.Imaging.ImageFormat.Bmp;
            break;

        case "png":
            Format = System.Drawing.Imaging.ImageFormat.Png;
            break;

        case "wmf":
            Format = System.Drawing.Imaging.ImageFormat.Wmf;
            break;

        case "gif":
            Format = System.Drawing.Imaging.ImageFormat.Gif;
            break;

    }
    return Format;
}