Case of Java realizing pdf to picture
- 2021-10-15 10:47:26
- OfStack
Project add dependencies:
<dependency>
<groupId>org.apache.pdfbox</groupId>
<artifactId>pdfbox</artifactId>
<version>2.0.15</version>
</dependency>
<dependency>
<groupId>org.apache.pdfbox</groupId>
<artifactId>pdfbox-tools</artifactId>
<version>2.0.15</version>
</dependency>
pdf file to picture:
public static List<String> pdf2Img(File pdfFile) {
if (pdfFile == null || !pdfFile.exists()) {
throw new RuntimeException("pdf File cannot be empty ");
}
String name = pdfFile.getName().substring(0, pdfFile.getName().lastIndexOf("."));
String targetPath = pdfFile.getParent() + File.separator + name;
List<String> imgList = new ArrayList<>();
try {
PDDocument doc = PDDocument.load(pdfFile);
// Number of pages
int pageCount = doc.getNumberOfPages();
PDFRenderer pdfRenderer = new PDFRenderer(doc);
for (int i = 0; i < pageCount; i++) {
File targetFile = new File(targetPath + File.separator + name + "-" + (i + 1) + ".jpg");
if (!targetFile.getParentFile().exists()) {
FileUtil.mkdir(targetFile.getParentFile());
}
pdfRenderer.renderImage(i);
BufferedImage image = pdfRenderer.renderImageWithDPI(i, 105, ImageType.RGB);
ImageIOUtil.writeImage(image, targetFile.getPath(), 105);
imgList.add(targetFile.getPath());
}
} catch (IOException e) {
log.error(" File conversion exception ", e);
throw new RuntimeException(" File conversion exception, err=" + e.getMessage());
}
pdf to 1 picture:
/**
* pdf Turn into 1 A picture
*
* @param pdfFile pdf Picture file
* @return Picture address
*/
public static String pdf2OneImg(File pdfFile) {
List<String> imgs = pdf2Img(pdfFile);
int len = imgs.size();
File[] src = new File[len];
BufferedImage[] images = new BufferedImage[len];
int[][] ImageArrays = new int[len][];
for (int i = 0; i < len; i++) {
try {
src[i] = new File(imgs.get(i));
if (!src[i].exists()) {
throw new RuntimeException(" Document " " + imgs.get(i) + " "Does not exist ");
}
images[i] = ImageIO.read(src[i]);
} catch (Exception e) {
log.error("", e);
throw new RuntimeException(e);
}
int width = images[i].getWidth();
int height = images[i].getHeight();
// Read from a picture RGB Pixel
ImageArrays[i] = new int[width * height];
ImageArrays[i] = images[i].getRGB(0, 0, width, height, ImageArrays[i], 0, width);
}
int dst_height = 0;
int dst_width = images[0].getWidth();
// Composite picture pixels
for (int i = 0; i < images.length; i++) {
dst_width = dst_width > images[i].getWidth() ? dst_width : images[i].getWidth();
dst_height += images[i].getHeight();
}
if (dst_height < 1) {
throw new RuntimeException(" File synthesis failed, the height of the synthesized picture file =" + dst_height);
}
String name = pdfFile.getName().substring(0, pdfFile.getName().lastIndexOf("."));
String targetPath = pdfFile.getParent() + File.separator + name;
// Output path
File outFile = new File(targetPath + File.separator + name + "-bigone.jpg");
// Generate a new picture
try {
dst_width = images[0].getWidth();
BufferedImage ImageNew = new BufferedImage(dst_width, dst_height, BufferedImage.TYPE_INT_RGB);
int height_i = 0;
for (int i = 0; i < images.length; i++) {
ImageNew.setRGB(0, height_i, dst_width, images[i].getHeight(), ImageArrays[i], 0, dst_width);
height_i += images[i].getHeight();
}
ImageIO.write(ImageNew, "jpg", outFile);
} catch (Exception e) {
log.error(" Image merge exception =", e);
throw new RuntimeException(e);
}
return outFile.getPath();
}