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Writing JPEG image in java as uncompressed still destroys data

I was making an application that hides data in LSBs of a JPEG image. Knowing that JPEG is a lossy compression and has a default compression of 70%, I changed it's parameters to 100% thus assuming that it wont destroy any data in the image. Here is the code.
File output = new File(gui.getOutput()+".jpg");
ImageWriter jpgWriter = ImageIO.getImageWritersByFormatName("jpg").next();
ImageWriteParam jpgWriteParam = jpgWriter.getDefaultWriteParam();
jpgWriteParam.setCompressionMode(ImageWriteParam.MODE_EXPLICIT);
jpgWriteParam.setCompressionQuality(1f);
FileImageOutputStream outputStream = new FileImageOutputStream(output);
jpgWriter.setOutput(outputStream);
IIOImage outputImage = new IIOImage(image, null, null);
jpgWriter.write(null, outputImage, jpgWriteParam);
jpgWriter.dispose();
The image that was created was indeed loss less, but the data I stored within the pixels were destroyed. (I checked it by reading the inserted data in the LSB and it wasn't the data I stored in the image).
What should I do to avoid the data being destroyed?

A must read api, and it only applies to quantization step

Inserting 1 MB image in neo4j returns a different size (536 KB) when retrieved

I am trying to insert a 1 MB image inside neo4j using the following code:
File fnew = new File("C:\\Users\\myimage.jpg");
BufferedImage originalImage = ImageIO.read(fnew);
ByteArrayOutputStream baos = new ByteArrayOutputStream();
baos.flus();
ImageIO.write(originalImage, "jpg", baos);
return baos.toByteArray();
Then I insert this byte array using:
user.setProperty("photo", photo);
This all goes fine. When I try to select the photo, using the following method, it writes it on my hard drive disk as 536KB instead of the 1 MB original size.
byte[] imageInByte = (byte[]) user.getProperty("photo");
InputStream in = new ByteArrayInputStream(imageInByte);
BufferedImage bImageFromConvert = ImageIO.read(in);
ImageIO.write(bImageFromConvert, "jpg", new File("C:\\newimage.jpg"));
Now the weird part: I can see the image, open it, same resolution, I don't see any difference in terms of quality though. Looks like it is compressed.
Why is this happening?

Saving a jpg image through ImageIO results in lossy compression of the jpg (I believe the quality defaults to 70%). You can a) Change the the quality of the image when you write to file (see Setting jpg compression level with ImageIO in Java ) or b) if you don't actually need the BufferedImage, just read/write the bytes from file to database.

PDFBOX JPG image is working but PNG not working

I had print an image into 'PDF' using the following code:
InputStream in = new FileInputStream(new File("C:/"+imageName));
PDJpeg img = new PDJpeg(doc, in);
contentStream.drawXObject(img, 20, pageYaxis-120, 80, 80);
Here when imagName="a.jpg" its working fine, In case of imagName="b.png" its not working. In jpg images its working but in png its not. Why it is so? Please help me. How can I make print both the formats, I mean format in depended?

In Apache PDFBox 1.8, use PDPixelMap for PNG images:
BufferedImage awtImage = ImageIO.read(new File(image));
ximage = new PDPixelMap(doc, awtImage);
In the source code of PDFBox, see the ImageToPDF.java example. This will work with all files that can be read with ImageIO. However it is still useful to keep using PDJpeg for JPG images, because there the JPEG files are directly put into the PDF files without being converted into a lossless format.

Bitmap alphaImage = BitmapFactory.decodeStream(in);
PDImageXObject alphaXimage = LosslessFactory.createFromImage(document, alphaImage);

How to read Bytes of an Image in Java?

I am currently working with Image processing in Java. Initially I used ImageIO class to write images
ImageIO.write(image,"jpg",os);
the problem with this method is am lossing the actual image size and quality. Then I preferred ByteStream
Files.readAllBytes(fi.toPath());
to read and
fos.write(fileContent);
to write Images. This works perfectly. The issue I am facing here is I can read only files but not Images(ie, BuffreredImage image). Is it possible to read a Image rather than files here or should I move to someother IO?
Code Snippet is here,
try {
File fnew=new File("d:\\3\\IMG1.jpg");
java.io.FileOutputStream fos = new java.io.FileOutputStream(new File("d:\\3\\Test1\\4.jpg"));
File fi = new File("d:\\3\\7.jpg");
byte[] fileContent = Files.readAllBytes(fi.toPath());
fos.write(fileContent);
} catch (Exception e) {
System.out.println("Exception");
}
Any Kind of suggestions or help will be appreciated. Thanks in Advance.

the problem with this method is am lossing the actual image size and quality. Then I preferred ByteStream
When you read a JPEG with with ImageIO, it is converting the JPEG to a Bitmap automatically. Then when you write it, it is encoding to a JPEG again (which loses quality).
Just replace ImageIO.write(image,"jpg",os) with ImageIO.write(image,"png",os) and you are done. A lossless format such as PNG will not lose any data when you write the image.

BufferedImage getRGB() will get you all the actual pixel data for the image. There will be no compression or anything like JPEG. It will be the raw image.
Edited to add an example based on my comments...
BufferedImage image = ImageIO.read(new File("google.jpg"));
ImageWriter w = ImageIO.getImageWritersBySuffix("jpg").next();
ImageOutputStream out = ImageIO.createImageOutputStream(new File("output.jpg"));
w.setOutput(out);
ImageWriteParam param = new JPEGImageWriteParam(Locale.getDefault());
param.setCompressionMode(ImageWriteParam.MODE_EXPLICIT);
param.setCompressionQuality(1);
w.write(null, new IIOImage(image, null, null), param);
out.close();

Convert a bitmap image to an uncompressed tif image in Java

I'm trying to convert a bitmap image into an uncompressed tif file for use with the Tesseract OCR engine.
I can use this method to produce a compressed tif file...
final BufferedImage bmp = ImageIO.read(new File("input.bmp"));
ImageIO.write(bmp, "jpg", new File("output.tif"));
This produces an empty tif file when the "jpg" is changed to tif as these files are dealt with in Java Advanced Imaging (JAI).
How can I create an uncompressed tif image? Should I decompress the tif image produced from the above code or is there another way to handle the conversion process?
Any examples provided would be much appreciated.
Thanks
kingh32

You can use ImageWriteParam to disable compression:
TIFFImageWriterSpi spi = new TIFFImageWriterSpi();
ImageWriter writer = spi.createWriterInstance();
ImageWriteParam param = writer.getDefaultWriteParam();
param.setCompressionMode(ImageWriteParam.MODE_DISABLED);
ImageOutputStream ios = ImageIO.createImageOutputStream(new File("output.tif"));
writer.setOutput(ios);
writer.write(null, new IIOImage(bmp, null, null), param);

Some time before i was facing the problems with tiff images reading and conversion with jai.
I found that it need to install support for working with tiff images in jai, then it works fine for me u can also get it form here:
https://cds.sun.com/is-bin/INTERSHOP.enfinity/WFS/CDS-CDS_Developer-Site/en_US/-/USD/ViewProductDetail-Start?ProductRef=jaiio-1.0_01-oth-JPR#CDS-CDS_Developer
and install over a jvm then it will also work for you.
you can also have a look here
Java / JAI - save an image gray-scaled