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How to confirm that image was taken with specific device?

I want to write function in my android application that will confirm that picture was
taken by specific mobile device.
Today I can tell, if the picture was taken by specific model. (like galaxy s3).
But,I want more than that.
I would like to get from image EXIF unique id and compare it to the device unique id.
Thanks for help.

Maybe instead of using a long code. You can use a pre-ready Library for that.
Metadata metadata = ImageMetadataReader.readMetadata(imageFile);
This is the example code used by the Library, https://drewnoakes.com/code/exif/
It would give you the MetaData for the image. Which is also the content you want, Like the GeoLocation, CellularInformation, Resolution, Focus and all other data attached to the image.
A qoutation from the link
It understands several formats of metadata, all of which may be present in a single image: In addition it can decode values that are specific to particular camera manufacturers and models.
Then you can check for the details on that image and show or hide or what so ever you want to do with that image.
You can get the code from Google Code too: https://code.google.com/p/metadata-extractor/
Good luck!

How to create a progressive JPEG image on Android

I need to send images over a very low-bandwidth connection from an android phone (down to 10kByte/s) and would like to send them in progressive (interlaced) mode so that the user at the other end starts seeing the image already during the lengthy transfer. Right now, I am creating the image with the regular photo app:
Intent takePictureIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
But this creates non-progressive photos and I have not been able to discover how to convince it to do otherwise. The second option I explored (reading and re-compressing the taken image) got foiled because the Bitmap's compress method does not allow any encoding parameters besides format name and compression factor as far as I could determine:
bitmap.compress(Bitmap.CompressFormat.JPEG, 80, out);
My preferred solution would be to instruct the photo app to save in progressive mode.
The next best option would be a Java algorithm that losslessly converts the stored jpeg to progressive (jpegtran does this on Linux, but it is in C and relies on libjepeg).
The next best would a method to specify the relevant encoding parameters to android allowing me to re-compress it, or an alternative Java library that does the same.
Further research revealed that the algorithms are already there (/system/lib/libjpeg.so) with the sources in ~/android-sdk-linux/source-tree/external/jpeg -- but there do not seem to be JNI wrappers readily available.

Have you seen this document?
http://docs.oracle.com/javase/6/docs/api/javax/imageio/plugins/jpeg/JPEGImageWriteParam.html
It seems to have write progressive support.
Alternatively, you could use e.g. OpenJPEG through JNI. See http://www.linux-mag.com/id/7697/ as a start.

Pure Java alternative to JAI ImageIO for detecting CMYK images

first I'd like to explain the situation/requirements that lead to the question:
In our web application we can't support CMYK images (JPEG) since IE 8 and below can't display them.
Thus we need to detect when someone wants to upload such an image and deny it.
Unfortunately, Java's ImageIO won't read those images or would not enable me to get the detected color space. From debugging it seems like JPEGImageReader internally gets the color space code 11 (which would mean JCS_YCCK) but I can't safely access that information.
When querying the reader for the image types I get nothing for CMYK, so I might assume no image types = unsupported image.
I converted the source CMYK image to RGB using an imaging tool in order to test whether it would then be readable (I tried to simulate the admin's steps when getting the message "No CMYK supported"). However, JPEGImageReader would not read that image, since it assumes (comment in the source!)3-component RGB color space but the image header reports 4 components (maybe RGBA or ARGB) and thus an IllegalArgumentException is thrown.
Thus, ImageIO is not an option since I can't reliably get the color space of an image and I can't tell the admin why an otherwise fine image (it can be displayed by the browser) would not be accepted due to some internal error.
This led me to try JAI ImageIO whose CLibJPEGImageReader does an excellent job and correctly reads all my test images.
However, since we're deploying our application in a JBoss that might host other applications as well, we'd like to keep them as isolated as possible. AFAIK, I'd need to install JAI ImageIO to the JRE or otherwise make the native libs available in order to use them, and thus other applications might get access to them as well, which might cause side effects (at least we'd have to test a lot to ensure that's not the case).
That's the explanation for the question, and here it comes again:
Is there any pure Java alternative to JAI ImageIO which reliably detects and possibly converts CMYK images?
Thanks in advance,
Thomas

I found a solution that is ok for our needs: Apache Commons Sanselan. This library reads JPEG headers quite fast and accurate (at least all my test images) as well as a number of other image formats.
The downside is that it won't read JPEG image data, but I can do that with the basic JRE tools.
Reading JPEG images for conversion is quite easy (the ones that ImageIO refuses to read, too):
JPEGImageDecoder decoder = JPEGCodec.createJPEGDecoder(new FileInputStream( new File(pFilename) ) );
BufferedImage sourceImg = decoder.decodeAsBufferedImage();
Then if Sanselan tells me the image is actually CMYK, I get the source image's raster and convert myself:
for( /*each pixel in the raster, which is represented as int[4]*/ )
{
double k = pixel[3] / 255.0;
double r = (255.0 - pixel[0])*k;
double g = (255.0 - pixel[1])*k;
double b = (255.0 - pixel[2])*k;
}
This give quite good results in the RGB images not being too bright or dark. However, I'm not sure why multiplying with k prevents the brightening. The JPEG is actually decoded in native code and the CMYK->RGB conversion I got states something different, I just tried the multiply to see the visual result.
If anybody could shed some light on this, I'd be grateful.

I've posted a pure Java solution for reading all sorts of JPEG images and converting them to RGB.
It's built on the following facts:
While ImageIO cannot read JPEG images with CMYK as a buffered image, it can read the raw pixel data (raster).
Sanselan (or Apache Commons Imaging as it's called now) can be used to read the details of CMYK images.
There are images with inverted CMYK values (an old Photoshop bug).
There are images with YCCK instead of CMYK (can easily be converted).

Beware of another post as the Java 7 does not allow to use directly Sun's implementation without special parameters as indicated in import com.sun.image.codec.jpeg.*.

In our web application we can't support CMYK images (JPEG) since
IE 8 and below can't display them. Thus we need to detect when someone
wants to upload such an image and deny it.
I don't agree with your "Thus we need to detect when someone wants to upload such an image and deny it". A much more user-friendly policy would be to convert it to something else than CMYK.
The rest of your post is a bit confusing in that regards seen that you ask both for detection and conversion, which are two different things. Once again, I think converting the image is much more user-friendly.
No need to write in bold btw:
Is there any pure Java alternative to JAI ImageIO which reliably
detects and possibly converts CMYK images?
Pure Java I don't know, but ImageMagick works fine to convert CMYK image to RGB ones. Calling ImageMagick on the server-side from Java really isn't complicated. I used to do it manually by calling an external process but nowadays there are wrappers like JMagick and im4java.

BarCode Image Generator in Java

How can I create a barcode image in Java? I need something that will allow me to enter a number and produce the corresponding barcode image. Is there a free library available for this type of task?

iText is a great Java PDF library. They also have an API for creating barcodes. You don't need to be creating a PDF to use it.
This page has the details on creating barcodes. Here is an example from that site:
BarcodeEAN codeEAN = new BarcodeEAN();
codeEAN.setCodeType(codeEAN.EAN13);
codeEAN.setCode("9780201615883");
Image imageEAN = codeEAN.createImageWithBarcode(cb, null, null);
The biggest thing you will need to determine is what type of barcode you need. There are many different barcode formats and iText does support a lot of them. You will need to know what format you need before you can determine if this API will work for you.

There is also this free API that you can use to make free barcodes in java.
Barbecue

There is a free library called barcode4j

ZXing is a free open source Java library to read and generate barcode images. You need to get the source code and build the jars yourself. Here's a simple tutorial that I wrote for building with ZXing jars and writing your first program with ZXing.
[http://www.vineetmanohar.com/2010/09/java-barcode-api/]

I use
barbeque
, it's great, and supports a very wide range of different barcode formats.
See if you like
its API
.
Sample API:
public static Barcode createCode128(java.lang.String data)
throws BarcodeException
Creates a Code 128 barcode that
dynamically switches between character
sets to give the smallest possible
encoding. This will encode all
numeric characters, upper and lower
case alpha characters and control
characters from the standard ASCII
character set. The size of the barcode
created will be the smallest possible
for the given data, and use of this
"optimal" encoding will generally
give smaller barcodes than any of the
other 3 "vanilla" encodings.

library for server side image resampling using java?

I want to create a serve resampled (downsized) version of images using jsp. The original images are stored in the database as blobs. I want to to create a jsp that serves a downsampled image with decent quality (not pixelated) as per the passed image width/height (e.g. getimage.jsp?imageid=xxxx&maxside=200) . Can you point me to a opensource api or code that I can call from the jsp page?

Java already contains libraries for image manipulation. It should be easy to resize an image and output it from a JSP.
This servlet looks like it does a very similar thing to what you want your JSP to do.

Is there anything wrong with the built-in Image.getScaledInstance(w, h, hints)? (*)
Use hints=Image.SCALE_SMOOTH to get non-horrible thumbnailing. Then use an ImageIO to convert to the required format for output.
*: well yes, there is something wrong with it, it's a bit slow, but really with all the other web overhead to worry about that's not likely to be much of an issue. It's also not the best quality for when upscaling images, where a drawImage with BICUBIC renderinghint is more suitable. But you're talking about downscaling only at the moment.
Be sure to check the sizes passed in so that you can't DoS your servlet by passing in enormous sizes causing a memory-eatingly-huge image to be created.