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Taking screenshot in Java (Robot, code working but not with external full screen application)

由 ▼魔方 西西 提交于 2019-12-01 00:23:00

Is this problem known,..

Yes. Typically it is caused by moving the rendering down to the level of the graphics card itself (largely side-stepping the OS).

..and how to fix this please?

AFAIU it cannot be fixed. Even native screenshot apps. will not manage to gain a screenshot of such a rendering.

Is this possible to simulate some "Print Screen" key in order to solve this problem? 

import java.awt.Robot;
import java.awt.Toolkit;
import java.awt.datatransfer.Clipboard;
import java.awt.datatransfer.DataFlavor;
import java.awt.event.KeyEvent;

public class ScreenshotUsingPrintScreen {

    public static void main(String[] args) throws Exception {
        int i = KeyEvent.VK_PRINTSCREEN;
        Clipboard cb = Toolkit.getDefaultToolkit().getSystemClipboard();
        DataFlavor[] flavors = cb.getAvailableDataFlavors();
        System.out.println("Before: ");
        for (DataFlavor flavor : flavors) {
            System.out.println(flavor);
        }

        // get the screenshot
        Robot robot = new Robot();
        robot.keyPress(KeyEvent.VK_PRINTSCREEN);
        robot.delay(40);
        robot.keyRelease(KeyEvent.VK_PRINTSCREEN);
        robot.delay(40);

        cb = Toolkit.getDefaultToolkit().getSystemClipboard();
        flavors = cb.getAvailableDataFlavors();
        System.out.println("After: ");
        for (DataFlavor flavor : flavors) {
            System.out.println(flavor);
        }
    }
}

Output

Before: 
java.awt.datatransfer.DataFlavor[mimetype=application/x-java-text-encoding;representationclass=[B]
java.awt.datatransfer.DataFlavor[mimetype=text/rtf;representationclass=java.io.InputStream]
java.awt.datatransfer.DataFlavor[mimetype=text/rtf;representationclass=java.nio.ByteBuffer]
java.awt.datatransfer.DataFlavor[mimetype=text/rtf;representationclass=[B]
java.awt.datatransfer.DataFlavor[mimetype=application/x-java-serialized-object;representationclass=java.lang.String]
java.awt.datatransfer.DataFlavor[mimetype=text/plain;representationclass=java.io.Reader]
java.awt.datatransfer.DataFlavor[mimetype=text/plain;representationclass=java.lang.String]
java.awt.datatransfer.DataFlavor[mimetype=text/plain;representationclass=java.nio.CharBuffer]
java.awt.datatransfer.DataFlavor[mimetype=text/plain;representationclass=[C]
java.awt.datatransfer.DataFlavor[mimetype=text/plain;representationclass=java.io.InputStream;charset=unicode]
java.awt.datatransfer.DataFlavor[mimetype=text/plain;representationclass=java.nio.ByteBuffer;charset=UTF-16]
java.awt.datatransfer.DataFlavor[mimetype=text/plain;representationclass=[B;charset=UTF-16]
java.awt.datatransfer.DataFlavor[mimetype=text/plain;representationclass=java.io.InputStream;charset=UTF-8]
java.awt.datatransfer.DataFlavor[mimetype=text/plain;representationclass=java.nio.ByteBuffer;charset=UTF-8]
java.awt.datatransfer.DataFlavor[mimetype=text/plain;representationclass=[B;charset=UTF-8]
java.awt.datatransfer.DataFlavor[mimetype=text/plain;representationclass=java.io.InputStream;charset=UTF-16BE]
java.awt.datatransfer.DataFlavor[mimetype=text/plain;representationclass=java.nio.ByteBuffer;charset=UTF-16BE]
java.awt.datatransfer.DataFlavor[mimetype=text/plain;representationclass=[B;charset=UTF-16BE]
java.awt.datatransfer.DataFlavor[mimetype=text/plain;representationclass=java.io.InputStream;charset=UTF-16LE]
java.awt.datatransfer.DataFlavor[mimetype=text/plain;representationclass=java.nio.ByteBuffer;charset=UTF-16LE]
java.awt.datatransfer.DataFlavor[mimetype=text/plain;representationclass=[B;charset=UTF-16LE]
java.awt.datatransfer.DataFlavor[mimetype=text/plain;representationclass=java.io.InputStream;charset=ISO-8859-1]
java.awt.datatransfer.DataFlavor[mimetype=text/plain;representationclass=java.nio.ByteBuffer;charset=ISO-8859-1]
java.awt.datatransfer.DataFlavor[mimetype=text/plain;representationclass=[B;charset=ISO-8859-1]
java.awt.datatransfer.DataFlavor[mimetype=text/plain;representationclass=java.io.InputStream;charset=windows-1252]
java.awt.datatransfer.DataFlavor[mimetype=text/plain;representationclass=java.nio.ByteBuffer;charset=windows-1252]
java.awt.datatransfer.DataFlavor[mimetype=text/plain;representationclass=[B;charset=windows-1252]
java.awt.datatransfer.DataFlavor[mimetype=text/plain;representationclass=java.io.InputStream;charset=US-ASCII]
java.awt.datatransfer.DataFlavor[mimetype=text/plain;representationclass=java.nio.ByteBuffer;charset=US-ASCII]
java.awt.datatransfer.DataFlavor[mimetype=text/plain;representationclass=[B;charset=US-ASCII]
After: 
java.awt.datatransfer.DataFlavor[mimetype=image/x-java-image;representationclass=java.awt.Image]
kmotawaze

The solution to your problem is right in front of you, try thinking differently. You don't need to use PrtScr function because almost all platforms (games) have an inbuilt screenshot function.

In Steam for example, this includes all games played through steam, F12 is used to take a screentshot. Instead of using PrtScr, use F12 in your code, the file is automatically stored, use that file, do what ever you like with it.

I know this is a bit late, but I hope it helps you with your project.

Edit to add exact code:

if (e.getKeyCode() == NativeKeyEvent.VC_0) {
    Robot robot = null;
    try {
        robot = new Robot();
        robot.keyPress(KeyEvent.VK_F12);
        robot.keyRelease(KeyEvent.VK_F12);
    } 
    catch (AWTException ex) {
        Logger.getLogger(JavaApplication6.class.getName()).log(Level.SEVERE, null, ex);
    }
}

This is in relation to steam, basically when you press "0", your program will simulate the input of F12, this will take a screenshot, which will be stored in "STEAM\userdata\137637106\760\remote\570\screenshots" directory.

Hope this helps.

标签
java
awt
fullscreen
screenshot
awtrobot
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