Develop Reference

Which image formats can be resized in JavaFX

There are about 100 jpeg & png color images used in our JavaFX-built desktop app which, when the window is resized, become stretched and blurry so I'd like to have all the graphics remade in a format that will allow them to be dynamically resized without losing quality. What image format or procedure should be used to do this?
Currently, each image is simply in an ImageView and resized as follows, but I'm open to other suggestions:
if(isSmall){
Rectangle2D visualBounds = Screen.getPrimary().getVisualBounds();
double sh = visualBounds.getHeight();
Scale scale = new Scale(sh, sh, 0, 0);
root.getTransforms().setAll(scale);
}

As has already been mentioned SVG is probably the way to go for you. JavaFX does not support SVG directly but you can find support here
javafxsvg and here svg-to-fxml-converter for example.

You can't resize an image to be bigger than it is without it getting blurry for most common formats. Instead make sure your images are big enough so you only need to downscale them.
The only format I ever heard of that could upscale further was using fractal compression, but AFAIK it is not in common use.

Android image strip and edit / combine 2 pictures

I want to create an android app that takes 2 pictures (taken from the phone camera). Takes the top part of pic1 and the bottom part of pic2 and combines them to the final picture.
I'm thinking about converting each image to byte array. Then take the half values from the array of the first image and the other half from the other image, merge them in the final array and convert that array back to image. Is it feasible? Is this a good solution or there is any better practice for this?

Well I guess I found the solution. There is a class in the Java6 API called "BufferedImage". This class has the methods: setRGB , getRGB where you can get the int value of the rgb color for the pixel you specify. This way you can get the pixel color from the image you want and set it in the target image.

Try using OpenCV. It will be very fast since it will be handling the images in native code. Convert Bitmap objects into Matrix(OpenCV) object and send the address to the native code where you can do these computations very easily. If any code is required, do let me know.

Java Picture Processing Framework

1) Load picture from byte array.
2) Verify it's current picture size.
3) Resize Picture according to my needs.
Is there any out of the box Java Framework which can help me to do it?
Thanks in advance.

Actually, java's default packages should be enough:
To load an image use javax.imageio.ImageIO.read(...)
To get it's size use the getWidth() and getHeight() of the returned BufferedImage object
To resize the image, you can: Create a new image (BufferedImage), acquire it's Grahpics objects, set the transformation, and then draw the original image.
Refer to the java working with images tutorial

I found thumbnailator to be very good.

Crop Bitmap without reading entire Bitmap first

I have a very large image and I only want to display a section the size of the display (no scaling), and the section should just be the center of the image. Because the image is very large I cannot read the entire image into memory and then crop it. This is what I have so far but it will give OutOfMemory for large images. Also I don't think inSampleSize applies because I want to crop the image, not lower the resolution.
Uri data = getIntent().getData();
InputStream is = getContentResolver().openInputStream(data);
Bitmap bitmap = BitmapFactory.decodeStream(is, null, null);
Any help would be great?

You can do this in 2 steps:
get the size of the bitmap, by using inJustDecodeBounds=true .
use BitmapRegionDecoder to decode just the part you want to .
The downside ? it works only from API 10 (but it's already the majority...).

I agree that the easiest way is to break the image up into many smaller tiled images and to just load the appropriate ones to make the image you are after.
However, if you do not want to do that, you may be forced to look into the encoding of the jpeg itself.
What you could do is something along the lines of copying the header from the file into a new file, and then extracting just the pixels you want in order to create a new file. Then reloading the new file will allow you to have just the subset of the image you are looking to work with, and all the regular java functionality and classes will be equally available for you to use.
I know it isn't necessarily an elegant or simple solution, however it does guarantee that you will be able to use the original java functionality which you expect to be able to use.

I think you're approaching the problem from the wrong direction.
If the bitmap is already so large it can't be loaded as a single continuous image, why store it as a single image? Slice it into tiles then load the center tile/tiles and act upon those.

How to save optimized png images with java's ImageIO?

I am generating lots of images in java and saving them through the ImageIO.write method like this:
final BufferedImage img = createSomeImage();
ImageIO.write( img, "png", new File( "/some/file.png" );
I was happy with the results until Google's firefox addon 'Page Speed' told me that i can save up to 60% of the size if i optimize the images. The images are QR codes, their size is around 900B each and the firefox-plugin optimized versions are around 300B.
I'd like to save such optimized 300B Images directly from java.
So here my question again: How to save optimized png images with java's ImageIO?

Use PngEncoderB to convert your BufferedImage into a PNG encoded byte array.
You can apply a filter to it, which helps prepare the image for better optimization. This is what OptiPNG does, only OptiPNG calculates which filter will get you the best compression.
You might have to try applying each filter to see which one is consistently better for you. With 2 bit color, I think the only filter that might help is "up", so I'm guessing that's the one to use.
Once you get the image to a PNG encoded byte array, you can write that directly to a file.