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How to draw transperent composite with border on image inside canvas in SWT java

I am creating one project in which user can select ROI from image with mouse drag event and selected ROI should be movable and resizable.
This is similar like windows paint does when we open image in paint.
How to make composite(like swt button, text) transparent on image (which is inside canvas).
I have created one canvas and added image in that. I can select ROI from mouse with the help of listener added to canvas(SWT.paint). Here I am taking bounds value and creating one composite to MOVE ROI. I am able to create composite on image, also I am able to move this ROI. But I am unable to make this created ROI transparent.
I am expecting the way windows paint works, same way my project should give me facility to select rectangle on image and move it.

Please try to set draw/fill color with alpha value.
In the below example 100 is the alpha value which set the transparency. 255 means no transparency.
Color color = new Color(255, 0, 0, 100);

saving bufferedimage to gif

I have an application that plots images on a JPanel. I want to dispose of the GUI altogether, so that the application is called from code only, with no user interface, and so that the images are saved to a gif file only.
I have experimented with code from this question, and it seems to work fine when I call the save gif code from within the old GUI. However, the save gif code is not seeming to work when I remove the GUI, and I am wondering if that might be because the JPanel it is trying to print has not actually made it to a GUI container like a JFrame, etc.
The reason I am not posting code is that it is too verbose, an I am just asking for a simple, boilerplate answer.
I have experimented with writeablerasters for other applications. But that would require a major recoding project for this application, which paints by using the graphics.drawLine() method. Can anyone suggest a code-efficient way to take contents of a "phantom" JPanel, get it into a BufferedImage, and then save it as a gif without ever putting the JPanel in a GUI?

Since your application draws on a JPanel then it just needs a Graphics object. You can use one from a BufferedImage which then you will save to file. Example code:
BufferedImage image = new BufferedImage(100, 100, BufferedImage.TYPE_INT_ARGB);
Graphics g = image.getGraphics();
// Pass this graphics object to your application to perform the drawing
g.setColor(Color.red);
g.drawRoundRect(10, 10, 20, 20, 5, 5);
// save it to disk
ImageIO.write(image, "png", new File("test.png"));

This is difficult to answer without any example code, however.
If the component you are trying to render is not displayed on the screen, it is likely that it has not being laid out.
Before painting, you should make sure you size the component.
componentToBePainted.setSize(componentToBePainted.getPreferredSize());
You should also be using print or printAll over paint. When not attached to a native peer, paint can cause issue

Is it possible to add transparency to jpg in Java and Android

I want to load some images to the cloud, but I want to add some protections when someone views the photos and saves the images; they will not see anything because of the transparency.
would the code be common for Java and Android? I would like to prototype it in Java first.
I have found some code that combines two files. One file is my main file the other is a transparent file. The combined file does not have a transparent overlay.
Do I need to use an image drawing order?
http://www.developer.nokia.com/document/Java_Developers_Library_v2/GUID-D3E35E6F-0C45-48ED-B09D-F716E14C1C02/javax/microedition/amms/control/imageeffect/OverlayControl.html
BufferedImage image = ImageIO.read(new File("rose.jpg"));
BufferedImage overlay = ImageIO.read(new File("myimg1.gif"));
// create the new image, canvas size is the max. of both image sizes
int w = Math.max(image.getWidth(), overlay.getWidth());
int h = Math.max(image.getHeight(), overlay.getHeight());
BufferedImage combined = new BufferedImage(w, h, BufferedImage.TYPE_INT_ARGB);
// paint both images, preserving the alpha channels
Graphics g = combined.getGraphics();
g.drawImage(image, 0, 0, null);
g.drawImage(overlay, 0, 0, null);
// Save as new image
ImageIO.write(combined, "PNG", new File("combined.png"));

This won't work. If they can see the image, they can copy it, one way or another. A solution to consider is providing watermarked thumbnails at no charge, then only offering the full resolution image for a fee. However, they can still copy the full resolution image once they pay.

You can actually put a trans image as an overlay to the orginial image, that will
Protect from download, I think this is usually done by the server side aka your cloud
I know from some websites that they use some kind of an overlay such as yours
And the browser can't see the image below so you can't download.
I actually didn't understand how you implementing this - the image is opened in the browser?
Just a wild though, you can also cut the image into pieces like a jigsaw puzzle
The device won't have problems connecting it togther but when you download you'll
Download only "one piece of the puzzle" :-P

Save graphics as image?

I'm developing an app for BlackBerry with Eclipse and want to know if there is any way to save a picture that is drawn with a Graphics object...The app involves drawing a pie chart using Graphics.It works fine the first time I open the screen to display the chart but the next time I try to create the chart by calling the screen, it goes haywire.So I was wondering if I can save the chart as an image...that way I wont have to keep drawing over and over everytime I open the screen...Please help...Thanks in advance!

I understood you are using the java.awt.Graphics class, right?
Ensure you are drawing only on the AWT event thread.
Use
SwingUtilities.invokeLater(new Runnable() {
public void run() {
// YOUR CODE
}
});
to run your saving code on the event thread. If you try to save from another thread, the image could get distorted if it is not drawn completely.

I don't know the blackberry API but you could take other aproach to your problem. You could do offscreen rendering. Create a BufferedImage, get a reference to its Graphics object, do the rendering and then save the BufferedImage as a png for example.
For example:
int width = 200, height = 200;
// TYPE_INT_ARGB specifies the image format: 8-bit RGBA packed
// into integer pixels
BufferedImage bi = new BufferedImage(width, height, BufferedImage.TYPE_INT_ARGB);
Graphics2D ig2 = bi.createGraphics();
// Draw your chart
ImageIO.write(bi, "PNG", new File("yourImageName.PNG"));
This way you can do all your drawing once, saving it as a file or just in memory (depends on what you need) and then you just need either to load the image from the file or do g.drawImage() in your screen.
But as i said before i don't know if this applies to the Blackberry API it works for sure with the JDK/JRE in a desktop.

Image manipulation using java

i'm trying to create a program that generates images for use as multi-screen backgrounds, i'm doing this targeted at windows (in my case, 7 so that basically i can get images to change without seeing the same image on two different screens)
in my program, i read multiple image input files and compile them into a single output image that is the total size of the desktop (including black areas not seen on screens)
my question is, what class/methods are good for cropping/resizing/pasting into a new image in java because i'm coming across so many image manipulation classes and they all seem to do one tiny thing.
i will not be modifying any of the images beyond resize or crop and putting it into a certain position in the new (initially blank) image.
code can be made available as i plan to release it at some later point for whoever may like/need it.
thank you in advance, if this question has been answered, my apologies but i DID have a look around.

I do not know if this is the best method, but it is quite easy:
// load an image
Image image = javax.imageio.ImageIO.read(new File("someimage.png");
// resize it
image = image.getScaledInstance(100, 100, Image.SCALE_SMOOTH);
// create a new image to render to
BufferedImage newimg = new BufferedImage(200,100,BufferedImage.TYPE_INT_ARGB);
// get graphics to draw..
Graphics2D graphics =newimg.createGraphics();
//draw the other image on it
graphics.drawImage(image,0,0,null);
graphics.drawImage(image,100,0,null);
graphics.fillOval(20,20,40,40); //making it a bit ugly ;)
//export the new image
ImageIO.write(newimg,"png",new File("output.png"));
//done!
For simplicity I dropped all checks, exception handling, etc.