在這篇文章中，我將會通過實例來解釋如何使用Aspose.BarCode for Java來識別PDF文檔中的條形碼。

生成條碼并插入PDF文檔

　　首先，我將啟用Aspose.BarCode for Java并生成一個條碼圖像。然后，將這個圖像保存到磁盤上的文件夾。接下來，我將使用Aspose.Words for Java 來創建一個Adobe PDF文檔，并將生成的條碼插入到PDF文檔中。

從PDF文檔中提取圖像并讀出條碼

　　對于識別部分，首先我會使用Aspose.Words for Java從PDF文檔中提取圖像。一旦提取圖像，我將會把這些圖像傳遞到Aspose.BarCode for Java中以便進行條碼識別。

　　以下代碼是一個完整的Java程序，可從Adobe PDF文檔生成和識別條碼：

[Java]

import com.aspose.barcode.*;

import com.aspose.barcoderecognition.BarCodeReadType;

import com.aspose.barcoderecognition.BarCodeReader;

import com.aspose.pdf.elements.Pdf;

import com.aspose.pdf.elements.Section;

import com.aspose.pdf.kit.License;

import com.aspose.pdf.kit.PdfExtractor;

import java.awt.Toolkit;

import java.io.File;

import java.io.FileInputStream;

import java.io.FileOutputStream;

public class RecognitionFromPdf

{

public static void main(String[] args)

{

try

{

// set license

License licPdfKit = new License();

FileInputStream stream = new FileInputStream("AsposeLicense.lic");

licPdfKit.setLicense(stream);

com.aspose.barcode.License licBarCode = new com.aspose.barcode.License();

licBarCode.setLicense("AsposeLicense.lic");

String strPdfDoc = " output1.pdf";

String strBarCodeImage = "";

// generate barcode and add to pdf file

BarCodeBuilder builder = new BarCodeBuilder();

builder.setSymbology(Symbology.CODE39STANDARD);

builder.setCodeText("test-123");

String strBarCodeImageSave = " img.jpg";

builder.save(strBarCodeImageSave);

//Instantiate a Pdf object by calling its empty constructor

Pdf pdf1 = new Pdf();

//Create a section in the Pdf object

Section sec1 = pdf1.getSections().add();

//Create an image object in the section

com.aspose.pdf.elements.Image img1 = new com.aspose.pdf.elements.Image(sec1);

//Add image object into the Paragraphs collection of the section

sec1.getParagraphs().add(img1);

//Set the path of image file

img1.getImageInfo().setFile(strBarCodeImageSave);

img1.getImageInfo().setTitle("JPEG image");

//Save the Pdf

FileOutputStream out = new FileOutputStream(new File(strPdfDoc));

pdf1.save(out);

//Instantiate PdfExtractor object

PdfExtractor extractor = new PdfExtractor();

//Bind the input PDF document to extractor

extractor.bindPdf(strPdfDoc);

//Extract images from the input PDF document

extractor.extractImage();

String suffix = ".jpg";

int imageCount = 1;

while (extractor.hasNextImage()) {

System.out.println("Extracting image " + imageCount);

strBarCodeImage = "tmpbarcode" + imageCount + suffix;

extractor.getNextImage(strBarCodeImage);

// recognize barcode from image

BarCodeReader reader = new BarCodeReader
(Toolkit.getDefaultToolkit().getImage(strBarCodeImage),
BarCodeReadType.Code39Standard);

while (reader.read())

{

System.out.println("codetext: " + reader.getCodeText());

}

imageCount++;

}

}

catch(Exception ex)

{

System.out.println(ex.getMessage());

}

}

}

下載《Aspose.BarCode for Java》