In my program,I am producing a png from a panel,but I want to get rid of the bounding box of
this panel and to be more focused to the object in the panel.To do so, I want to get rid of the peripheral parts of png, and produce only the center of it.How can i do that ?
Assuming that you already have your image loaded into a BufferedImage (which seems to be the case), this code will crop the image from (x,y) to (width,height).
image = image.getSubimage(x, y, width, height);
Then save as normal.
Related
I am loading an external image with JavaFX:
Image tile = new Image(imageFile.toURI().toURL().toString(),width, height, true,true);
You need to supply the width and height. How can I get the image's width and height?
Now, I know that the width and height of a PNG image are determined by the bytes from 12 to 20 or something like that, so technically you could open a byte stream and interpret the bytes. However, this seems overkill for the simple task of drawing an image in my JavaFX application. Is there not a way to draw an image with its full size without asking me to supply the dimensions?
Just create the Image using a constructor which does not include dimensions (e.g. new Image(url)):
Image image = new Image(url);
I have two RenderedImages. I want to do an Overlay Operation with these two images and therefore they need to match in data type and the number of bands.
The problem I have is that one image has 3 bands (RGB) and the second image has 4 bands (ARGB).
My question is how can I add an Alpha Channel to the first image so I can do the Overlay Operation?
EDIT
Ok, I found a method of adding an Alpha Channel to the first image. Below is the code. I simply created a single banded constant image and merged it with my first image.
ParameterBlock pb = new ParameterBlock();
pb.add(new Float(finalImage.getWidth())).add(new Float(finalImage.getHeight()));
pb.add(new Byte[] {new Byte((byte)0xFF)});
RenderedImage alpha = JAI.create("constant", pb);
finalImage = BandMergeDescriptor.create(finalImage, alpha, null);
The problem I have now is that everytime I add an overlay the image changes colors. All the colors become nuances of red or pink. When I add a second overlay, the image becomes normal again, but the first overlay changes colors. All black areas become white.
Also the background of the overlay is not transparent. It is grey.
Below are examples of the images, so you see how the change colors:
As you can see, the picture and overlays change colors and the background of the overlay isn't transparent.
Can you help me solve this problem, so that the image is always displayed correctly? Thanks!
You can try to create a new BufferedImage with ARGB-model, and just paint the non-transparent background picture into this new BufferedImage. Then you have a BufferedImage with alpha-channel (although all of the pixels are opaque), so the Composition should hopefully work.
im not sure about TYPE_4BYTE_ARGB as I usually work with BufferedImages of TYPE_INT_ARGB but I have often used the method of drawing a RGB BufferedImage to a new ARGB BufferedImage and then drawing that onto other things without problem. the change in color would suggest an unwanted change is being made to the other channels in the overlay process as it doesn't seem to be specific to a specific image. If your overlay operation is similar to drawing one image onto another with alpha I would probably suggest using the Graphics.drawImage()/drawRenderedImage() method for the overlay itself not to mention the background should not even need alpha in this case.
the code:
public RenderedImage overlay(RenderedImage back, RenderedImage front, AffineTransform overlayTransformation)
{
BufferedImage newBack = new BufferedImage(back.getWidth(), back.getHeight(), TYPE_3BYTE_RGB);
newBack.setData(back.getData());
Graphics2D graphics = (Graphics2D)(newBack.getGraphics());
graphics.drawRenderedImage(front, overlayTransformation);
return newBack;
}
you may want to ensure the original back Raster is not modified though.
I'm making a simple side scroller game in Java but am having trouble making the camera move with the person. My plan was to create a buffered image that could adjust the region of the image that is displaying and simply have it follow my character. However, I couldn't find any functions in the API to change the region of the buffered image that's displayed, so how could I do this? Thanks for any help provided.
//The level is created in an 800x400 pixel size, is there any way I can change
//the region myImage displays?
myImage = new BufferedImage(400, 400, BufferedImage.TYPE_INT_RGB);
Well while you will be drawing your image you have a lot of options for example this function can draw any rectangle from your original image on any rectangle of the surface you get Graphics object from.
I want to inset a image into a background and save it, both are png files with transparency, below code work fine but new image become black & white only.
BufferedImage BUFFEREDIMAGE1=ImageIO.read(new File(strPATH+"/IMAGE.png"));
BufferedImage BUFFEREDIMAGE2=ImageIO.read(new File(strPATH+"/WATERMARK.png"));
Graphics2D GRAPHICS1=BUFFEREDIMAGE1.createGraphics();
GRAPHICS1.drawImage(BUFFEREDIMAGE2,intLeft,intTop,intWidth,intHeight,null);
GRAPHICS1.dispose();
ImageIO.write(BUFFEREDIMAGE2,"png",new File(strPATH,"SAVED.png"));
The most likely cause is that at some point the colour space of the image is becoming changed. You may be better off explicitly creating a new destination BufferedImage with the RGB or RGBA format and writing both source Images into it. This removes any possible variation in that area.
I am making a game in Java. I made a planet seen from outer space and I want to make it appear like the planet is slowly rotating. But I don't know how to rotate a image. I need a simple command that rotates my image 1 degree around its own center once. Any help?
This is what I want to do:
Image
Take a look at these tutorials:
Java2D: Have Fun With Affine Transform
Coordinate Translations and Rotations: Example Code
Transforming Shapes, Text, and Images
What you are describing is not rotating an image, but changing an image to represent a 3D rotation of the object in the image.
Ideally you wouldn't be working with this as an image but rather as a 3D object with a different camera angle. Then you would simply rotate the camera around the object and display the resulting image to the user.
However if you're set on doing this as an image, then you need to create a different images representing various states of rotation of your planet and have a separate thread that would replace the displayed image with the next one in sequence, at repeated intervals. Search the web for "java image animation" - there are plenty of tutorials on how to do this.
If you want to rotate an image in 2d space, you can use something like this:
Image image = ...
Graphics2D g2d = ...; //
g2d.translate(170, 0); // If needed
g2d.rotate(1); // Rotate the image by 1 radian
//or g2d.rotate(180.0/3.14); to rotate by 1 degree
g2d.drawImage(image, 0, 0, 200, 200, observer);