Java BufferedImage how to know if a pixel is transparent

java transparency bufferedimage
Panos picture Panos · Jan 23, 2012 · Viewed 8.6k times · Source

I'm going to use the getRGB method of BufferedImage. I want to check the pixels of an image and see which of them have transparency (in general the pixels I will have that are transparent will be totaly transparent). How can I get it from the int that getRGB returns?

Answer

chubbsondubs picture chubbsondubs · Jan 23, 2012 
BufferedImage img = ....

public boolean isTransparent( int x, int y ) {
  int pixel = img.getRGB(x,y);
  if( (pixel>>24) == 0x00 ) {
      return true;
  }
  return false;
}

Of course img has to be in the correct format TYPE_4BYTE_ABGR or some format that supports alpha channels else if will always be opaque (ie 0xff).

Related questions

Java: Filling a BufferedImage with transparent pixels

I have an off-screen BufferedImage, constructed with the type BufferedImage.TYPE_INT_ARGB. It can contain anything, and I'm looking for a way to (fairly efficiently) completely overwrite the image with transparent pixels, resulting in an 'invisible' image. Using something …

Read More
How to read pixel color in a java BufferedImage with transparency

I am reading pixel color in a BufferedImage as follows: ..... InputStream is = new BufferedInputStream(conn.getInputStream()); BufferedImage image = ImageIO.read(is); int color = image.getRGB(x, y); int red = (colour & 0x00ff0000) >> 16; int green = (colour & 0x0000…

Read More
BufferedImage producing black background

Alright so I'm making a game, and I'm trying to modify the original hit marker image by adding text on it, and I'm using the following code: import javax.swing.ImageIcon; import javax.swing.Timer; import java.awt.Color; import …

Read More