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Image byte stream is different when file is read in different ways

Under my Spring 4.3/Maven 3.3 project I have an image file, a PNG file, at:
src/main/resources/images/account.png
I have a util java application file that reads in an image, and it writes it to the database field. The code is as follows:
private static String _accountFilename = "src/main/resources/images/account.png";
private byte[] getByteArrayFromFile(String filename)
{
FileInputStream fileInputStream = null;
File file = new File(filename);
byte[] bFile = new byte[(int) file.length()];
try
{
// convert file into array of bytes
fileInputStream = new FileInputStream(file);
fileInputStream.read(bFile);
fileInputStream.close();
for (int i = 0; i < bFile.length; i++)
{
System.out.print((char) bFile[i]);
}
System.out.println("Done");
}
catch (Exception e)
{
e.printStackTrace();
}
return bFile;
}
public String getImageData(byte[] imageByteArray)
{
Base64.Encoder encoder = Base64.getEncoder();
String base64 = encoder.encodeToString(imageByteArray);
base64 = "data:image/png;base64," + base64;
return base64;
}
The String that comes back from "getImageData" works great. I can put that String in the MySQL database, in a table, and the field is defined as TEXT.
I can pull that base64 encoded data back, and display the image.
Now, If I am calling this code from a Spring Service instead of an application, then the image "src/main/resources/images/account.png" is not found.
After researching on the Net for some time, there are many, many examples of getting a file from "resources" and many of these did not work for me. Since I am in Spring, I tried a few things and finally this worked:
#Value(value = "classpath:images/account.png")
private Resource defaultAccountImage;
private byte[] getByteArrayFromFile(Resource image)
{
InputStream inputStream = null;
byte[] bFile = null;
try
{
bFile = new byte[(int) image.contentLength()];
// convert file into array of bytes
inputStream = image.getInputStream();
inputStream.read(bFile);
inputStream.close();
for (int i = 0; i < bFile.length; i++)
{
System.out.print((char) bFile[i]);
}
System.out.println("Done");
}
catch (Exception e)
{
e.printStackTrace();
}
return bFile;
}
private String getImageData(byte[] imageByteArray)
{
Base64.Encoder encoder = Base64.getEncoder();
String base64 = encoder.encodeToString(imageByteArray);
base64 = "data:image/png;base64," + base64;
return base64;
}
public String getDefaultAccountImage()
{
byte[] accountImage = getByteArrayFromFile(defaultAccountImage);
String fileString = getImageData(accountImage);
return fileString;
}
When I look at the String/Image data between the first way with the standalone java app, and the second way with the #Value and inputstream, there is a definite different in the string data.
part of the string data is similar, but then it drastically changes, and they don't match. As a result the text data for the image from the second method doesn't display as an image.
So, I was hoping I could get this image text data, and it would be the same, but it is not. If I can use my web-service, which calls the business service which calls this ImageUtil code where I use the #Value to get the image resource and it saves the text string correctly, that would be great.
If you have any advice, I would very much appreciate it. Thanks!
UPDATE 1:
This is a multi-maven project:
parent-project
entity
dao
service
ws
When I run my test code within the Service layer, the suggested solution works great! The images are found and the byte string gets loaded as it should be. And then I compiled the code into a jar.
The entity.jar gets created first.
The dao.jar gets created and pulls in the entity.jar.
The service.jar gets created and pulls in the dao.jar. This layer also has the /resources/images/account.png file. But this image is now in the jar.
The ws.WAR file pulls in the service.jar file ...
so the code in the answer does not find the image in the resources.
When I run the tests from the ws layer, I get a FileNotFoundException.
So ... now I am researching on how to get an image from jar ...
Does this change how I should be getting my image byte array?

You can get the file from the Resource, and proceed like the first example which works. Seems redundant, but if you can get the file, then you can test a number of things:
Write the file to disk and check the content
Write the file to disk and compare the sizes, etc.
import java.io.File;
import java.io.FileInputStream;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.core.io.Resource;
#Value(value = "classpath:images/account.png")
private Resource defaultAccountImage;
private byte[] getByteArrayFromFile(Resource image) {
FileInputStream fileInputStream = null;
byte[] bFile = null;
try {
File file = image.getFile();
bFile = new byte[(int) file.length()];
// convert file into array of bytes
fileInputStream = new FileInputStream(file);
fileInputStream.read(bFile);
fileInputStream.close();
for (int i = 0; i < bFile.length; i++) {
System.out.print((char) bFile[i]);
}
System.out.println("Done");
} catch (Exception e) {
e.printStackTrace();
}
return bFile;
}

OCR implementation using using java

I have written java code to convert images into text using java.But my code is taking only single image as input . I want that the program should fetch images from a folder and then run the OCR on it.
My code is:
import java.io.FileOutputStream;
import org.bytedeco.javacpp.*;
import org.junit.Test;
import static org.bytedeco.javacpp.lept.*;
import static org.bytedeco.javacpp.tesseract.*;
import static org.junit.Assert.assertTrue;
import java.io.File;
public class BasicTesseractExampleTest {
#Test
public void givenTessBaseApi_whenImageOcrd_thenTextDisplayed() throws Exception {
BytePointer outText;
TessBaseAPI api = new TessBaseAPI();
// Initialize tesseract-ocr with English, without specifying tessdata path
if (api.Init(".", "ENG") != 0) {
System.err.println("Could not initialize tesseract.");
System.exit(1);
}
PIX image = pixRead("IMG_0012 (1).jpg");
api.SetImage(image);
// Get OCR result
outText = api.GetUTF8Text();
String string = outText.getString();
assertTrue(!string.isEmpty())
System.out.println(str);
// Destroy used object and release memory
api.End();
outText.deallocate();
pixDestroy(image);
}
}

To read a list of files out of a given Path use for example:
File f = new File("C:/programs");
File[] fileArray = f.listFiles();
Now you can check every File out of the fileArray if it is a directory and skip that with:
if(fileArray[0].isDirectory()) continue;
To find the images you can check for example the ending of the filename with:
fileArray[0].getName().endsWith(".jpg")
Do this check for all files out ouf the fileArray and call your method with the right files. To check the right file you have to change this line of your code:
PIX image = pixRead("IMG_0012 (1).jpg");
and add the fileArray[?] where the ? must be replaced with the right number.

Write Base64-encoded image to file

How to write a Base64-encoded image to file?
I have encoded an image to a string using Base64.
First, I read the file, then convert it to a byte array and then apply Base64 encoding to convert the image to a string.
Now my problem is how to decode it.
byte dearr[] = Base64.decodeBase64(crntImage);
File outF = new File("c:/decode/abc.bmp");
BufferedImage img02 = ImageIO.write(img02, "bmp", outF);
The variable crntImage contains the string representation of the image.

Assuming the image data is already in the format you want, you don't need ImageIO at all - you just need to write the data to the file:
// Note preferred way of declaring an array variable
byte[] data = Base64.decodeBase64(crntImage);
try (OutputStream stream = new FileOutputStream("c:/decode/abc.bmp")) {
stream.write(data);
}
(I'm assuming you're using Java 7 here - if not, you'll need to write a manual try/finally statement to close the stream.)
If the image data isn't in the format you want, you'll need to give more details.

With Java 8's Base64 API
byte[] decodedImg = Base64.getDecoder()
.decode(encodedImg.getBytes(StandardCharsets.UTF_8));
Path destinationFile = Paths.get("/path/to/imageDir", "myImage.jpg");
Files.write(destinationFile, decodedImg);
If your encoded image starts with something like data:image/png;base64,iVBORw0..., you'll have to remove the part. See this answer for an easy way to do that.

No need to use BufferedImage, as you already have the image file in a byte array
byte dearr[] = Base64.decodeBase64(crntImage);
FileOutputStream fos = new FileOutputStream(new File("c:/decode/abc.bmp"));
fos.write(dearr);
fos.close();

import java.util.Base64;
.... Just making it clear that this answer uses the java.util.Base64 package, without using any third-party libraries.
String crntImage=<a valid base 64 string>
byte[] data = Base64.getDecoder().decode(crntImage);
try( OutputStream stream = new FileOutputStream("d:/temp/abc.pdf") )
{
stream.write(data);
}
catch (Exception e)
{
System.err.println("Couldn't write to file...");
}

Other option using apache-commons:
import org.apache.commons.codec.binary.Base64;
import org.apache.commons.io.FileUtils;
...
File file = new File( "path" );
byte[] bytes = Base64.decodeBase64( "base64" );
FileUtils.writeByteArrayToFile( file, bytes );

Try this:
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.net.URL;
import javax.imageio.ImageIO;
public class WriteImage
{
public static void main( String[] args )
{
BufferedImage image = null;
try {
URL url = new URL("URL_IMAGE");
image = ImageIO.read(url);
ImageIO.write(image, "jpg",new File("C:\\out.jpg"));
ImageIO.write(image, "gif",new File("C:\\out.gif"));
ImageIO.write(image, "png",new File("C:\\out.png"));
} catch (IOException e) {
e.printStackTrace();
}
System.out.println("Done");
}
}

Print PDF that contains JBIG2 images

Please, suggest me some libraries that will help me print PDF files that contain JBIG2 encoded images. PDFRenderer, PDFBox don't help me. These libs can print simple PDF, but not PDF containing JBIG2 images. PDFRenderer tries to fix it (according to bug issue on PDFRedndrer's bug tracker), but some pages still (especially where barcodes exist) don't want to print.
P.S. I use javax.print API within applet
Thanks!
UPDATE: also tried ICEPdf, is too don't want to work.
I came to the conclusion that all these libraries(PDFRenderer, ICEPdf, PDFBox) use JPedals jbig2 decoder. Bug (some pages didn't print) come from this decoder library. The open source version of this decoder (which is used in PDFRenderer, ICEPdf, PDFBox) is no longer supported, but JPedal has a new commercial branch of the project, and they wrote that the bug has been fixed in new commercial release, which costs $9k.
Any ideas?
UPDATE 2: yesterday I tried to replace JPedal's free library with other open-source jbig2-imageio libraries. But yet I don't get any successful results, so I created a new topic on their project's page (google-code's forum - here ). Would be grateful for any help.
I also found some helpfull discussions on Apache PDFBox bug-tracker: here and here.

As going through your comment in yms answer ie. " but what library I can use to extract images and (more importantly) put them back in PDF?"
Here is a simple demonstration of
1 ) Extracting jbig2 or you can say all images from pdf.
2 ) Converting jbig2 image to any other format, in my case its jpeg.
3 ) Creating new pdf containing the jpeg.
Using libraries jbig2-imageio and itext.
In the below example please change the resources and the directories path as per your need.
For this I had to go through several resources that I will attach in the end. Hope this helps.
import com.itextpdf.text.Document;
import com.itextpdf.text.Image;
import com.itextpdf.text.pdf.PdfPCell;
import com.itextpdf.text.pdf.PdfPTable;
import com.itextpdf.text.pdf.PdfReader;
import com.itextpdf.text.pdf.PdfWriter;
import com.itextpdf.text.pdf.parser.*;
import com.levigo.jbig2.JBIG2ImageReader;
import com.levigo.jbig2.JBIG2ImageReaderSpi;
import com.levigo.jbig2.JBIG2ReadParam;
import com.levigo.jbig2.io.DefaultInputStreamFactory;
import java.awt.image.BufferedImage;
import java.io.*;
import javax.imageio.ImageIO;
import javax.imageio.stream.ImageInputStream;
public class JBig2Image {
private String filepath;
private int imageIndex;
public JBig2Image() {
this.filepath = "/home/blackadmin/Desktop/pdf/demo18.jbig2";
this.imageIndex = 0;
extractImgFromPdf();
convertJBig2ToJpeg();
createPDF();
}
private void extractImgFromPdf() {
try {
/////////// Extract all Images from pdf /////////////////////////
PdfReader reader = new PdfReader("/home/blackadmin/Desktop/pdf/orig.pdf");
PdfReaderContentParser parser = new PdfReaderContentParser(reader);
MyImageRenderListener listener = new MyImageRenderListener("/home/blackadmin/Desktop/pdf/demo%s.%s");
for (int i = 1; i <= reader.getNumberOfPages(); i++) {
parser.processContent(i, listener);
}
} catch (IOException ex) {
System.out.println(ex);
}
}
private void convertJBig2ToJpeg() {
InputStream inputStream = null;
try {
///////// Read jbig2 image ////////////////////////////////////////
inputStream = new FileInputStream(new File(filepath));
DefaultInputStreamFactory disf = new DefaultInputStreamFactory();
ImageInputStream imageInputStream = disf.getInputStream(inputStream);
JBIG2ImageReader imageReader = new JBIG2ImageReader(new JBIG2ImageReaderSpi());
imageReader.setInput(imageInputStream);
JBIG2ReadParam param = imageReader.getDefaultReadParam();
BufferedImage bufferedImage = imageReader.read(imageIndex, param);
////////// jbig2 to jpeg ///////////////////////////////////////////
ImageIO.write(bufferedImage, "jpeg", new File("/home/blackadmin/Desktop/pdf/demo18.jpeg"));
} catch (IOException ex) {
System.out.println(ex);
} finally {
try {
inputStream.close();
} catch (IOException ex) {
System.out.println(ex);
}
}
}
public void createPDF() {
Document document = new Document();
try {
PdfWriter.getInstance(document,
new FileOutputStream("/home/blackadmin/Desktop/pdf/output.pdf"));
document.open();
PdfPTable table = new PdfPTable(1); //1 column.
Image image = Image.getInstance("/home/blackadmin/Desktop/pdf/demo18.jpeg");
image.scaleToFit(800f, 600f);
image.scaleAbsolute(800f, 600f); // Give the size of image you want to print on pdf
PdfPCell nestedImgCell = new PdfPCell(image);
table.addCell(nestedImgCell);
document.add(table);
document.close();
System.out.println(
"======== PDF Created Successfully =========");
} catch (Exception e) {
System.out.println(e);
}
}
public static void main(String[] args) throws IOException {
new JBig2Image();
}
}
class MyImageRenderListener implements RenderListener {
/**
* The new document to which we've added a border rectangle.
*/
protected String path = "";
/**
* Creates a RenderListener that will look for images.
*/
public MyImageRenderListener(String path) {
this.path = path;
}
/**
* #see com.itextpdf.text.pdf.parser.RenderListener#beginTextBlock()
*/
public void beginTextBlock() {
}
/**
* #see com.itextpdf.text.pdf.parser.RenderListener#endTextBlock()
*/
public void endTextBlock() {
}
/**
* #see com.itextpdf.text.pdf.parser.RenderListener#renderImage(
* com.itextpdf.text.pdf.parser.ImageRenderInfo)
*/
public void renderImage(ImageRenderInfo renderInfo) {
try {
String filename;
FileOutputStream os;
PdfImageObject image = renderInfo.getImage();
if (image == null) {
return;
}
filename = String.format(path, renderInfo.getRef().getNumber(), image.getFileType());
os = new FileOutputStream(filename);
os.write(image.getImageAsBytes());
os.flush();
os.close();
} catch (IOException e) {
System.out.println(e.getMessage());
}
}
/**
* #see com.itextpdf.text.pdf.parser.RenderListener#renderText(
* com.itextpdf.text.pdf.parser.TextRenderInfo)
*/
public void renderText(TextRenderInfo renderInfo) {
}
}
References :
1 ) Extracting jbig2 from pdf (extract images) (MyImageRenderListener).
2 ) Converting jbig2 (JBIG2ImageReaderDemo)

There is a fork of the JPedal library by Borisvl located at
https://github.com/Borisvl/JBIG2-Image-Decoder#readme
which contains speed improvements and I believe it should also fix your bug.
EDIT : The bug is related to simple range checking. Basically you need to prevent GetPixel from accessing x,y values outside of the bitmap extents.
You need to make sure the following conditions are met before calling getPixel
col >= 0 and col < bitmap.width
row >= 0 and row < bitmap.height
Here is some Delphi code with a couple of small range checks. I cannot test the Java code myself but you need to make changes to src/org/jpedal/jbig2/image/JBIG2Bitmap.java
procedure TJBIG2Bitmap.combine(bitmap: TJBIG2Bitmap; x, y: Integer; combOp: Int64);
...
...
var
begin
srcWidth := bitmap.width;
srcHeight := bitmap.height;
srcRow := 0;
srcCol := 0;
if (x < 0) then x := 0;
if (y < 0) then y := 0;
for row := y to Min(y + srcHeight - 1, Self.height - 1) do // <<<<<<<< HERE
begin
for col := x to x + srcWidth - 1 do
begin
srcPixel := bitmap.getPixel(srcCol, srcRow);
Andrew.

How about using AcrobatReader itself? It's a bit muddy getting it to work, and not a robust solution I guess. But will probably print all of it perfectly. And be free
Some info about this route;
http://vineetreynolds.blogspot.nl/2005/12/silent-print-pdf-print-pdf.html
http://www.codeproject.com/Questions/98586/Programmatically-print-PDF-documents
http://forums.adobe.com/message/2336723

You have tools as ImageMagick which handle images and convert them to a lot of formats. I used it some years ago so I can't tell you if the jbig2 format is properly handled by default or if you have to install some plugin.
You can try the following to have a list of supported formats beginning with J like the JBIG2 you are searching for:
$ convert -list format | grep -i J
It is really obvious to convert to pdf with with tool too, coupled with gs tool aka GhostScript.
If fact nothing prevent you to display a PNG/JPEG version of the image and provide a download link to the original JBIG2 file with its own metadatas.

As an alternative, you could try doing this server-side:
Approach 1:
Convert the PDF files to raster images using an external application and print that instead.
Approach 2:
Adjust your PDF files by recompressing JBIG2 images:
1- Extracting the images compressed as JBIG2 from your files.
2- Re-compress them with some other algorithm (jpeg, png, etc). In order to do this you might need to go outside of Java using either JNI or calling an external application. You can try with jbig2dec or ImageMagic for example if the GPL lincense suits your needs.
3- Put the recompressed images back in your PDF.
This approach will imply some quality loss on those images, but at least you will be able to print the files.
You can do this in Java with iText, there is a chapter about resizing images in the book iText in Action (with sample code). The idea there is to extract the image, resize it (including recompression) and put it back. You can use this as starting point. Be aware that iText is an AGPL project, hence you cannot use it for free in commercial closed-source applications.
If you are using a Windows-based server and you can afford a commercial tool, you can also achieve this with Amyuni PDF Creator either with C#/VB.Net or C++ (Usual disclaimer applies for this suggestion). You just need to go though all objects of type acObjectTypePicture and set the attribute Compression to acJPegHigh, this approach does not require any external JBIG2 decoder, (I can include some sample code here if you are interested).
If you are using an applet just to print your PDF files, you could also try generating a PDF file that shows the print dialog when opened

Java get image extension/type using BufferedImage from URL

I am familiar with working with images. I retrieve/read an image from a URL, where the URL does not have a file extension. Then I wish to write/save the image to the local storage, but I have to specify the image file extension (i.e. JPG, PNG, etc.), which I cannot retrieve its extension through the BufferedImage.
Could one please point out how it can be done?
Any other method will do.

Use ImageReader.getFormatName()
You can get the image readers for a file using ImageIO.getImageReaders(Object input).
I haven't tested it myself, but you can try this:
ImageInputStream iis = ImageIO.createImageInputStream(file);
Iterator<ImageReader> imageReaders = ImageIO.getImageReaders(iis);
while (imageReaders.hasNext()) {
ImageReader reader = (ImageReader) imageReaders.next();
System.out.printf("formatName: %s%n", reader.getFormatName());
}

The suggestion to use ImageIO.createImageInputStream(obj) will not work if the object is a URL.
One alternative is to use the URLConnection.guessContentTypeFromStream(InputStream stream) method. This method guesses the content type by examining the first 12 bytes of a stream.
One complication with using this method is that it requires the given stream parameter to be mark supported, and the stream returned by java url.openStream() is not mark supported.
Additionally, if you want to be determine the content type and download the image to a BufferedImage, then it would be preferable if the solution only downloaded the content once (as opposed to making two passes, once to determine the content type and a second time to download the image).
One solution is to use the PushbackInputStream. The PushbackInputStream can be used to download the first initial bytes to determine content type. The bytes can then be pushed back on the stream so that the ImageIO.read(stream) can read the stream in its entirety.
Possible solution:
// URLConnection.guessContentTypeFromStream only needs the first 12 bytes, but
// just to be safe from future java api enhancements, we'll use a larger number
int pushbackLimit = 100;
InputStream urlStream = url.openStream();
PushbackInputStream pushUrlStream = new PushbackInputStream(urlStream, pushbackLimit);
byte [] firstBytes = new byte[pushbackLimit];
// download the first initial bytes into a byte array, which we will later pass to
// URLConnection.guessContentTypeFromStream
pushUrlStream.read(firstBytes);
// push the bytes back onto the PushbackInputStream so that the stream can be read
// by ImageIO reader in its entirety
pushUrlStream.unread(firstBytes);
String imageType = null;
// Pass the initial bytes to URLConnection.guessContentTypeFromStream in the form of a
// ByteArrayInputStream, which is mark supported.
ByteArrayInputStream bais = new ByteArrayInputStream(firstBytes);
String mimeType = URLConnection.guessContentTypeFromStream(bais);
if (mimeType.startsWith("image/"))
imageType = mimeType.substring("image/".length());
// else handle failure here
// read in image
BufferedImage inputImage = ImageIO.read(pushUrlStream);

If you get the image from a URL, that means you can access the image through an InputStream. From that you can use ImageIO to get the image type (format) and with the following code, create a BufferedImage at the same time.
public static BufferedImageWrapper getImageAndTypeFromInputStream(InputStream is) {
String format = null;
BufferedImage bufferedimage = null;
try (ImageInputStream iis = ImageIO.createImageInputStream(is);) {
Iterator<ImageReader> readers = ImageIO.getImageReaders(iis);
if (readers.hasNext()) {
ImageReader reader = readers.next();
format = reader.getFormatName();
reader.setInput(iis);
bufferedimage = reader.read(0);
}
} catch (IOException e) {
logger.error("ERROR DETERMINING IMAGE TYPE!!!", e);
}
return new BufferedImageWrapper(format, bufferedimage);
}
public static class BufferedImageWrapper {
private final String imageType;
private final BufferedImage bufferedimage;
/**
* Constructor
*
* #param imageType
* #param bufferedimage
*/
public BufferedImageWrapper(String imageType, BufferedImage bufferedimage) {
this.imageType = imageType;
this.bufferedimage = bufferedimage;
}
public String getImageType() {
return imageType;
}
public BufferedImage getBufferedimage() {
return bufferedimage;
}
}

This works by feeding in a URL object (that is an image), and returning a file extension
It requires an initial download though, to the java tmp directory, and it is then deleted after the ImageReader attempts to get the gather the image type
import javax.imageio.ImageIO;
import javax.imageio.stream.ImageInputStream;
import javax.imageio.ImageReader;
import java.util.Iterator;
public String getImageFileExtFromUrl(URL urlObject) throws URISyntaxException, IOException{
System.out.println("IN DOWNLOAD FILE FROM URL METHOD");
String tmpFolder = System.getProperty("java.io.tmpdir");
String tmpFileStr = tmpFolder + "/" + new Date().getTime();
Files.copy(urlObject.openStream(), Paths.get(tmpFileStr), StandardCopyOption.REPLACE_EXISTING);
File download = new File(tmpFileStr);
System.out.println("FILE DOWNLOAD EXISTS: " + download.exists() );
try{
ImageInputStream iis = ImageIO.createImageInputStream(download);
Iterator<ImageReader> iter = ImageIO.getImageReaders(iis);
ImageReader reader = iter.next();
String formatName = reader.getFormatName();
System.out.println("FOUND IMAGE FORMAT :" + formatName);
iis.close();
return formatName;
}catch(Exception e){
e.printStackTrace();
}finally{
Files.delete(Paths.get(tmpFileStr));
}
return null;
}