We Keep Coding

Loading jpg image over mat frame opencv java

I have hand detection code right now that creates a green rectangle around the hand when detected. However, I want to fill the rectangle with another jpeg image. I was thinking of using ImagePattern where the image gets embedded inside the shape however that did not seem to work in my program.
Here is my code for creating the rectangle around the hand :
Imgproc.rectangle(frame, handsArray[i].tl(), handsArray[i].br(), new Scalar(0, 255, 0), 3);
The frame is a Mat and Imgproc is a opencv, javacv function.
Can someone please help me with this problem? I am struggling
Regards
Green Rectangle Around The Hand that needs to be filled
BufferedImage bi = null;
try {
bi = ImageIO.read(new File(trollFace));
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
Mat mat = new Mat(bi.getHeight(), bi.getWidth(), CvType.CV_8UC3);
byte[] data = ((DataBufferByte) bi.getRaster().getDataBuffer()).getData();
mat.put(0, 0, data);

You can do it in these steps:
Submat the rectangle from your source image
Mat submat = src.submat(new Rect(200, 200, 100, 100));
Now copy the sencond image into the submat
src2.copyTo(submat);
Note: Before copying, insure the size of the second image is the same as the rectangle, if not you can use the resize() function of the Imgprc class to resize the Mat. And it is that.
Update: The below is the example.
Mat src = Imgcodecs.imread("C:\\src1.jpg");
Mat src2 = Imgcodecs.imread("C:\\src2.jpg");
Imgproc.resize(src2, src2, new Size(100, 100));
Mat submat = src.submat(new Rect(200, 200, 100, 100));
src2.copyTo(submat);
// now you can do what you want with the src1

Convert color image into black and white using java created from scratch

I want to convert my picture from colored to Black and white which seems to be created from scratch.
Here is the code which i tried as described on the different post:
BufferedImage bi = ImageIO.read(new File("/Users/***/Documents/Photograph.jpg"));
ColorConvertOp op =
new ColorConvertOp(ColorSpace.getInstance(ColorSpace.CS_GRAY), null);
ImageIO.write(bi, "PNG", new File("/Users/bng/Documents/rendered2.png"));
op.filter(bi, bi);
But still my image is not converted to the Black and white. Additionally, this code is increasing the rendered2.png image size to 10 folds.
Also, it would be great if i could find some Java 8 way of doing this.
Any suggestions?

Here is the code which worked for me:
BufferedImage input = ImageIO.read(new File("/Users/bng/Documents/Photograph.jpg"));
// Create a black-and-white image of the same size.
BufferedImage im = new BufferedImage(input.getWidth(), input.getHeight(), BufferedImage.TYPE_BYTE_BINARY);
// Get the graphics context for the black-and-white image.
Graphics2D g2d = im.createGraphics();
// Render the input image on it.
g2d.drawImage(input, 0, 0, null);
// Store the resulting image using the PNG format.
ImageIO.write(im, "PNG", new File("/Users/bng/Documents/rendered.png"));
It was BufferedImage.TYPE_BYTE_BINARY which provided me the exact solution.
Lokking for the Java 8 Version for above code.

You have to find RGB of the existing colors of the image you want to change it.
Fyi, you want to change it as white RGB value is (255,255,255) and for black RGB value is (0,0,0)
Following method easily do the color change if you apply correct way of your requirement
private BufferedImage changeColor(BufferedImage image, int srcColor, int replaceColor)
{
BufferedImage destImage = new BufferedImage(image.getWidth(), image.getHeight(), BufferedImage.TYPE_INT_ARGB);
Graphics2D g = destImage.createGraphics();
g.drawImage(image, null, 0, 0);
g.dispose();
for (int width = 0; width < image.getWidth(); width++)
{
for (int height = 0; height < image.getHeight(); height++)
{
if (destImage.getRGB(width, height) == srcColor)
{
destImage.setRGB(width, height, replaceColor);
}
}
}
return destImage;
}

you have to use the ColorConvertOp in a proper way:
create Source image
apply filter
save dest
example:
BufferedImage src = ImageIO.read(new File("/Users/***/Documents/Photograph.jpg"));
ColorConvertOp op =
new ColorConvertOp(ColorSpace.getInstance(ColorSpace.CS_GRAY), null);
BufferedImage dest = op.filter(src, null);
ImageIO.write(dest, "PNG", new File("/Users/bng/Documents/rendered2.png"));
src:
dest:

Get a specific version of the icon of a file in Java

I was looking at this question and I was looking at the first answer.
So I tried to use this code:
public static Image getIcon(String fileName) throws Exception {
File file = new File(fileName);
FileSystemView view = FileSystemView.getFileSystemView();
Icon icon = view.getSystemIcon(file);
ImageIcon imageIcon = (ImageIcon) icon;
Image image = imageIcon.getImage();
return image;
}
Which does return an Image (or throws an Error) but the Image has terribly low resolution.
I am assuming that this is because the 16x16 Image is returned.
Is there any way to state which Image I want to be returned?

Java offers you two possibilities to retrieve file icons.
You already know the first one:
Icon icon = FileSystemView.getFileSystemView().getSystemIcon(new File(FILENAME));
that gives you a 16x16 pixel result.
The other one using ShellFolder
Icon icon = new ImageIcon(ShellFolder.getShellFolder(new File(FILENAME)).getIcon(true));
will retrieve you the larger one (32x32) depending on the boolean flag getLargeIcon in the getIcon method.
I'm sorry for you but more is (at the moment) not possible with the java default libraries. Interest exists as you can read in this JDK bugreport.
But nothing has been done so far.
If you really want to have larger versions you will need to retrieve them with the OS depending native calls or store them manually as local application ressources.
Note: If you have problems accessing ShellFolder you should read this question.

I used this method:
protected ImageIcon getImageIcon() {
File f = new File((iconPath!=null)?iconPath:"");
if (!f.isFile() || !f.canRead()) {
iconPath = Constants.getDefaultPreviewIconPath();
}
ImageIcon icon = new ImageIcon(iconPath, titolo);
return new ImageIcon(Utils.getScaledImage(
icon.getImage(),
Constants.getICON_WIDTH(),
Constants.getICON_HEIGTH()));
}
where getScaledImage is:
public static Image getScaledImage(Image srcImg, int w, int h) {
BufferedImage resizedImg = new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB);
Graphics2D g2 = resizedImg.createGraphics();
g2.setRenderingHint(RenderingHints.KEY_INTERPOLATION, RenderingHints.VALUE_INTERPOLATION_BILINEAR);
g2.drawImage(srcImg, 0, 0, w, h, null);
g2.dispose();
return resizedImg;
}

Find format of clipboard image in Java

I'm getting images from clipboard using this:
if(Toolkit.getDefaultToolkit().getSystemClipboard().isDataFlavorAvailable(DataFlavor.imageFlavor)){
ImageIcon IMG = new ImageIcon((BufferedImage) Toolkit.getDefaultToolkit().getSystemClipboard().getData(DataFlavor.imageFlavor));
}
Now I want to save this image in disk using ImageIO.write;
How can I find image format (JPG,PNG,GIF,...) to use in ImageIO.write as formatName ?
Thanks

The mime type of the content of the clipboard when checked via
.isDataFlavorAvailable(DataFlavor.imageFlavor)
is image/x-java-image (but OS vendors do not need to follow MIME types for clipboards).
I found two ways to supposedly get an image from a clipboard and write it to a file:
Using a helper method found in this blog post: The nightmares of getting images from the Mac OS X clipboard using Java.
Clipboard clip = Toolkit.getDefaultToolkit().getSystemClipboard()
ImageIcon IMG = new ImageIcon((BufferedImage)
clip.getData(DataFlavor.imageFlavor));
BufferedImage bImage = getBufferedImage(IMG.getImage());
ImageIO.write(bImage, "png", new File("/tmp/test.png"));
The getBufferedImage method looks like this:
public static BufferedImage getBufferedImage(Image img) {
if (img == null) {
return null;
}
int w = img.getWidth(null);
int h = img.getHeight(null);
// draw original image to thumbnail image object and
// scale it to the new size on-the-fly
BufferedImage bufimg = new BufferedImage(w, h,
BufferedImage.TYPE_INT_RGB);
Graphics2D g2 = bufimg.createGraphics();
g2.setRenderingHint(RenderingHints.KEY_INTERPOLATION,
RenderingHints.VALUE_INTERPOLATION_BILINEAR);
g2.drawImage(img, 0, 0, w, h, null);
g2.dispose();
return bufimg;
}
Via Transferable. Note that this runs on OS X but produces an empty image of the correct size:
Clipboard clip = Toolkit.getDefaultToolkit().getSystemClipboard()
Transferable content =
clip.getContents(null);
BufferedImage img = (BufferedImage) content.getTransferData(
DataFlavor.imageFlavor);
ImageIO.write(img, "png", new File("/tmp/test.png"));

Creating image of a panel just creates a panel image rather then the stuff present on the panel

I am writing a code to make an image file of a chart appearing on a panel. For that purpose I create the buffered image of that and then use ImageIO.write(). It works but it only displays the panel(grey coloured panel) but does not show the chart present on that panel. What to do in this case?? Here is my code
com.objectplanet.chart.NonFlickerPanel p =
new com.objectplanet.chart.NonFlickerPanel(new BorderLayout());
p.add("Center", chart); // this statements adds the chart in the center of the panel
ChartPanel.add("Center", p);
ChartPanel.setSize(500, 200);
ChartPanel.show();
int w = ChartPanel.getWidth();
int h = ChartPanel.getHeight();
BufferedImage bi = new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB);
Graphics2D g = bi.createGraphics();
ChartPanel.paint(g);
ChartPanel.printAll(g);
File f = new File("D:\\image.png");
try {
// png is an image format (like gif or jpg)
ImageIO.write(bi, "png", f);
} catch (IOException ex) {
ex.printStackTrace();
}
Well i solved the problem .Anyone facing the same problem ,here is the solution
Use paintall function rather than just paint function