使用pdfbox从pdf中提取图像 [英] extract images from pdf using pdfbox

问题描述

我试图使用pdfbox从pdf中提取图像。示例pdf 此处

I m trying to extract images from a pdf using pdfbox. The example pdf here

但我只是获得空白图片。

But i m getting blank images only.

我正在尝试的代码： -

The code i m trying:-

public static void main(String[] args) {
   PDFImageExtract obj = new PDFImageExtract();
    try {
        obj.read_pdf();
    } catch (IOException ex) {
        System.out.println("" + ex);
    }

}

 void read_pdf() throws IOException {
    PDDocument document = null; 
    try {
        document = PDDocument.load("C:\\Users\\Pradyut\\Documents\\MCS-034.pdf");
    } catch (IOException ex) {
        System.out.println("" + ex);
    }
    List pages = document.getDocumentCatalog().getAllPages();
    Iterator iter = pages.iterator(); 
    int i =1;
    String name = null;

    while (iter.hasNext()) {
        PDPage page = (PDPage) iter.next();
        PDResources resources = page.getResources();
        Map pageImages = resources.getImages();
        if (pageImages != null) { 
            Iterator imageIter = pageImages.keySet().iterator();
            while (imageIter.hasNext()) {
                String key = (String) imageIter.next();
                PDXObjectImage image = (PDXObjectImage) pageImages.get(key);
                image.write2file("C:\\Users\\Pradyut\\Documents\\image" + i);
                i ++;
            }
        }
    }

}

谢谢

推荐答案

以下是使用PDFBox 2.0.1的代码，它将获取PDF中所有图像的列表。这与其他代码的不同之处在于它将通过文档递归而不是尝试从顶层获取图像。

Here is code using PDFBox 2.0.1 that will get a list of all images from the PDF. This is different than the other code in that it will recurse through the document instead of trying to get the images from the top level.

public List<RenderedImage> getImagesFromPDF(PDDocument document) throws IOException {
        List<RenderedImage> images = new ArrayList<>();
    for (PDPage page : document.getPages()) {
        images.addAll(getImagesFromResources(page.getResources()));
    }

    return images;
}

private List<RenderedImage> getImagesFromResources(PDResources resources) throws IOException {
    List<RenderedImage> images = new ArrayList<>();

    for (COSName xObjectName : resources.getXObjectNames()) {
        PDXObject xObject = resources.getXObject(xObjectName);

        if (xObject instanceof PDFormXObject) {
            images.addAll(getImagesFromResources(((PDFormXObject) xObject).getResources()));
        } else if (xObject instanceof PDImageXObject) {
            images.add(((PDImageXObject) xObject).getImage());
        }
    }

    return images;
}

这篇关于使用pdfbox从pdf中提取图像的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！