java 如何使用pdfbox获取字体颜色

How to get font color using pdfbox

提问by Neeraj

I am trying to extract text with all information from the pdf using pdfbox. I got all the information i want, except color. I tried different ways to get the fontcolor (including Getting Text Colour with PDFBox). But not working. And now I copied code from PageDrawer class of pdfBox. But then also the RGB value is not correct.

我正在尝试使用 pdfbox 从 pdf 中提取包含所有信息的文本。我得到了我想要的所有信息，除了颜色。我尝试了不同的方法来获取字体颜色（包括使用 PDFBox 获取文本颜色）。但不工作。现在我从 pdfBox 的 PageDrawer 类中复制了代码。但是RGB值也不正确。

protected void processTextPosition(TextPosition text) {

        Composite com;
        Color col;
        switch(this.getGraphicsState().getTextState().getRenderingMode()) {
        case PDTextState.RENDERING_MODE_FILL_TEXT:
            com = this.getGraphicsState().getNonStrokeJavaComposite();
            int r =       this.getGraphicsState().getNonStrokingColor().getJavaColor().getRed();
            int g = this.getGraphicsState().getNonStrokingColor().getJavaColor().getGreen();
            int b = this.getGraphicsState().getNonStrokingColor().getJavaColor().getBlue();
            int rgb = this.getGraphicsState().getNonStrokingColor().getJavaColor().getRGB();
            float []cosp = this.getGraphicsState().getNonStrokingColor().getColorSpaceValue();
            PDColorSpace pd = this.getGraphicsState().getNonStrokingColor().getColorSpace();
            break;
        case PDTextState.RENDERING_MODE_STROKE_TEXT:
            System.out.println(this.getGraphicsState().getStrokeJavaComposite().toString());
            System.out.println(this.getGraphicsState().getStrokingColor().getJavaColor().getRGB());
           break;
        case PDTextState.RENDERING_MODE_NEITHER_FILL_NOR_STROKE_TEXT:
            //basic support for text rendering mode "invisible"
            Color nsc = this.getGraphicsState().getStrokingColor().getJavaColor();
            float[] components = {Color.black.getRed(),Color.black.getGreen(),Color.black.getBlue()};
            Color  c1 = new Color(nsc.getColorSpace(),components,0f);
            System.out.println(this.getGraphicsState().getStrokeJavaComposite().toString());
            break;
        default:
            System.out.println(this.getGraphicsState().getNonStrokeJavaComposite().toString());
            System.out.println(this.getGraphicsState().getNonStrokingColor().getJavaColor().getRGB());
    }

I am using the above code. The values getting are r = 0, g = 0, b = 0, inside cosp object value is [0.0], inside pd object array = null and colorSpace = null. and RGB value is always -16777216. Please help me. Thanks in advance.

我正在使用上面的代码。得到的值是 r = 0, g = 0, b = 0, 在 cosp 对象中值为 [0.0], 在 pd 对象数组中 = null 和 colorSpace = null。并且 RGB 值始终为 -16777216。请帮我。提前致谢。

采纳答案by demongolem

I tried the code in the link you posted and it worked for me. The colors I get back are 148.92, 179.01001 and 214.965. I wish I could give you my PDF to work with, maybe if I store it externally to SO? My PDF used a sort of palish blue color and that seems to match. It was just one page of text created in Word 2010 and exported, nothing too intense.

我尝试了您发布的链接中的代码，它对我有用。我得到的颜色是 148.92、179.01001 和 214.965。我希望我可以给你我的 PDF 来使用，也许如果我将它存储在 SO 的外部？我的 PDF 使用了一种淡蓝色，看起来很匹配。它只是在 Word 2010 中创建并导出的一页文本，没有太强烈的内容。

A couple of suggestions ....

几个建议......

1. Recall that the value returned is a float between 0 and 1. If a value is accidentally cast to int, then of course the values will end up containing nearly all 0. The linked to code multiples by 255 to get a range of 0 to 255.
2. As the commenter said, the most common color for a PDF file is black which is 0 0 0

1. 回想一下，返回的值是一个介于 0 和 1 之间的浮点数。如果一个值意外地转换为 int，那么当然这些值最终将包含几乎所有的 0。链接到代码乘以 255 以获得 0 到 255 的范围.
2. 正如评论者所说，PDF 文件最常见的颜色是黑色，即 0 0 0

That is all I can think of now, otherwise I have version of 1.7.1 of pdfbox and fontbox and like I said I pretty much followed the link you gave.

这就是我现在能想到的全部，否则我有 pdfbox 和 fontbox 的 1.7.1 版本，就像我说的那样，我几乎按照您提供的链接进行操作。

EDIT

编辑

Based upon my comments, here perhaps is a minorly invasive way of doing it for pdf files like color.pdf?

根据我的评论，对于 pdf 文件，这可能是一种微创方式，例如color.pdf？

In PDFStreamEngine.javain the processOperatormethod one can do inside the try block

在PDFStreamEngine.java的processOperator方法可以try块内做

if (operation.equals("RG")) {
   // stroking color space
   System.out.println(operation);
   System.out.println(arguments);
} else if (operation.equals("rg")) {
   // non-stroking color space
   System.out.println(operation);
   System.out.println(arguments);
} else if (operation.equals("BT")) {
   System.out.println(operation);    
} else if (operation.equals("ET")) {
   System.out.println(operation);           
}

This will show you the information, then it is up to you to process the color information for each section according to your needs. Here is a snippet from the beginning of the output of the above code when run on color.pdf...

这将显示信息，然后由您根据需要处理每个部分的颜色信息。这是上面代码在运行时输出开头的片段color.pdf...

BT rG [COSInt(1), COSInt(0), CosInt(0)] RG [COSInt(1), COSInt(0), CosInt(0)] ET BT ET BT rG [COSFloat{0.573}, COSFloat{0.816}, COSFloat{0.314}] RG [COSFloat{0.573}, COSFloat{0.816}, COSFloat{0.314}] ET ......

BT rG [COSInt(1), COSInt(0), CosInt(0)] RG [COSInt(1), COSInt(0), CosInt(0)] ET BT ET BT rG [COSFloat{0.573}, COSFloat{0.816}, COSFloat{0.314}] RG [COSFloat{0.573}, COSFloat{0.816}, COSFloat{0.314}] ET ......

You see in the above output an empty BT ET section, this being a section which is marked DEVICEGRAY. All the other give you [0,1] values for the R, G and B components

您在上面的输出中看到一个空的 BT ET 部分，这是一个标记为 DEVICEGRAY 的部分。所有其他为您提供 R、G 和 B 分量的 [0,1] 值

回答by kiranbkrishna

I also ended up doing something like this. Pasting code below, hope it helps someone.

我也最终做了这样的事情。粘贴代码如下，希望对大家有所帮助。

import java.io.IOException;
import java.util.List;
import org.apache.pdfbox.exceptions.COSVisitorException;
import org.apache.pdfbox.pdmodel.PDDocument;
import org.apache.pdfbox.pdmodel.PDPage;
import org.apache.pdfbox.pdmodel.edit.PDPageContentStream;
import org.apache.pdfbox.pdmodel.font.PDFont;
import org.apache.pdfbox.pdmodel.font.PDType1Font;
import org.apache.pdfbox.pdmodel.graphics.PDGraphicsState;
import org.apache.pdfbox.util.PDFTextStripper;
import org.apache.pdfbox.util.ResourceLoader;
import org.apache.pdfbox.util.TextPosition;

public class Parser extends PDFTextStripper {

public Parser() throws IOException {
    super(ResourceLoader.loadProperties(
            "org/apache/pdfbox/resources/PageDrawer.properties", true));
    super.setSortByPosition(true);
}

public void parse(String path) throws IOException{
    PDDocument doc = PDDocument.load(path);
    List<PDPage> pages = doc.getDocumentCatalog().getAllPages();
    for (PDPage page : pages) {
        this.processStream(page, page.getResources(), page.getContents().getStream());
    }
}

@Override
protected void processTextPosition(TextPosition text) {
    try {
        PDGraphicsState graphicsState = getGraphicsState();
        System.out.println("R = " + graphicsState.getNonStrokingColor().getJavaColor().getRed());
        System.out.println("G = " + graphicsState.getNonStrokingColor().getJavaColor().getGreen());
        System.out.println("B = " + graphicsState.getNonStrokingColor().getJavaColor().getBlue());
    }
    catch (IOException ioe) {}

}

public static void main(String[] args) throws IOException, COSVisitorException {
    Parser p = new Parser();
    p.parse("/Users/apple/Desktop/123.pdf");
}

}

回答by Jubin Patel

I found some code in one of my maintenance program.
I do not know it works for you or not, please try It. Also check out this link http://pdfbox.apache.org/apidocs/org/apache/pdfbox/pdmodel/common/class-use/PDStream.html

我在我的一个维护程序中找到了一些代码。
我不知道它是否适合您，请尝试一下。另请查看此链接http://pdfbox.apache.org/apidocs/org/apache/pdfbox/pdmodel/common/class-use/PDStream.html

It may help you

它可能会帮助你

PDDocument doc = null;
try {
    doc = PDDocument.load("C:/Path/To/Pdf/Sample.pdf");
    PDFStreamEngine engine = new PDFStreamEngine(ResourceLoader.loadProperties("org/apache/pdfbox/resources/PageDrawer.properties"));
    PDPage page = (PDPage)doc.getDocumentCatalog().getAllPages().get(0);
    engine.processStream(page, page.findResources(), page.getContents().getStream());
    PDGraphicsState graphicState = engine.getGraphicsState();
    System.out.println(graphicState.getStrokingColor().getColorSpace().getName());
    float colorSpaceValues[] = graphicState.getStrokingColor().getColorSpaceValue();
    for (float c : colorSpaceValues) {
        System.out.println(c * 255);
    }
}
finally {
    if (doc != null) {
        doc.close();
    }

回答by Robert Lill

With the pdfbox verson 2.0+ it is necessary to choose these operators in the constructor of your overwritten PDFTextStripper:

对于 pdfbox 版本 2.0+，有必要在覆盖的 PDFTextStripper 的构造函数中选择这些运算符：

addOperator(new SetStrokingColorSpace());
addOperator(new SetNonStrokingColorSpace());
addOperator(new SetStrokingDeviceCMYKColor());
addOperator(new SetNonStrokingDeviceCMYKColor());
addOperator(new SetNonStrokingDeviceRGBColor());
addOperator(new SetStrokingDeviceRGBColor());
addOperator(new SetNonStrokingDeviceGrayColor());
addOperator(new SetStrokingDeviceGrayColor());
addOperator(new SetStrokingColor());
addOperator(new SetStrokingColorN());
addOperator(new SetNonStrokingColor());
addOperator(new SetNonStrokingColorN());

Only then getGraphicsState() will return proper information.

只有这样 getGraphicsState() 才会返回正确的信息。

See https://pdfbox.apache.org/2.0/migration.html

见https://pdfbox.apache.org/2.0/migration.html