Re: Screen recording needs a performance boost.
On Jul 20, 7:54 pm, "Andrew Thompson" <u32984@uwe> wrote:
pyro9...@gmail.com wrote:
I'm using robot to capture my screen in "real-time" and only able to
pull about 12fps, does anyone know how to improve the fps? Is the
while loop slowing it down?
Of course it is! The code is setting up try/catch constructs,
instantiating objects, updating a number of GUI elements,
scaling images, ..and creating a screencapture of the entire
screen!
..
Any help or idea's is appreciated.
Here is my altered code, and test results..
Oh, and while I recall, please post SSCCE's, rather
than code snippets..
<http://www.physci.org/codes/sscce.html>
<sscce>
import java.awt.*;
import javax.swing.*;
public class AnimatedScreenCapture extends JFrame {
JLabel jLabel1;
Robot robot;
Rectangle rectangle1;
int scaleX;
int scaleY;
public AnimatedScreenCapture() {
super("Animated Screen Capture");
setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
jLabel1 = new JLabel();
jLabel1.setPreferredSize(new Dimension(400,300));
getContentPane().add( jLabel1 );
rectangle1 = new Rectangle(100,100);
scaleX = Toolkit
.getDefaultToolkit()
.getScreenSize()
.width / 2;
scaleY =Toolkit
.getDefaultToolkit()
.getScreenSize()
.height / 2;
try {
robot = new java.awt.Robot();
} catch (AWTException e) {
e.printStackTrace();
System.exit(-1);
}
}
public void startCapture2() {
long t0 = System.currentTimeMillis();
int i = 0;
int fps = 0;
while (true) {
i++;
long t1 = System.currentTimeMillis();
int seconds = (int) (t1-t0)/1000;
if (i%1000==0 && seconds>0) {
fps = i / seconds;
this.setTitle("FPS: " + fps);
}
Image screen_capture = robot
.createScreenCapture(rectangle1)
.getScaledInstance(scaleX, scaleY, Image.SCALE_FAST)
;
jLabel1.setIcon(new ImageIcon(screen_capture));
jLabel1.update(jLabel1.getGraphics());
}
}
public static void main(String[] args) throws AWTException {
Thread t = new Thread() {
public void run() {
AnimatedScreenCapture asc = new AnimatedScreenCapture();
asc.pack();
asc.setVisible(true);
asc.startCapture2();
}
};
SwingUtilities.invokeLater(t);
}}
</sscce>
Results:
FPS Conditions
3 original code (screen size 1024x768)
3 instantiated robot in constructor
4 replaced try/catch on division with test for 0.
20-22 screencap2 with rect of 100,100
250-290+ " " " " " and no scale
520-600+ " " " " " and no label update
540+ " " " " " and no label update/scale
It seems most of the time is taken up scaling the image
and updating the GUI. This should be done in a separate
thread.
This is not a good project for a newbie.
--
Andrew Thompsonhttp://www.athompson.info/andrew/
Message posted via JavaKB.comhttp://www.javakb.com/Uwe/Forums.aspx/java-setup/200707/1
Thanks for your time! I appreciate your efforts. I'll remember to give
usable code in the future. I guess in my head I was expecting there
to be some sort of obvious problem with my code. Not sure about your
"not a good project for a newbie" comment though.. I'm not new to
programming, I'm just newer to Java, and I've never done anything
multi-threaded so I figured this project would be good. Either way,
I'm moving on because I'm having fun.
I changed the screen area size captured to the full desktop resolution
and found that your application isn't any faster then mine. However,
your comments and code gave me some idea's on improving mine, and I've
gained about 5fps.
This is what I've come up with for the code (the GUI is in a seperate
class file, and isn't included)
import java.awt.AWTException;
import java.awt.Image;
import java.awt.Rectangle;
import java.awt.Robot;
import java.awt.Toolkit;
import javax.swing.ImageIcon;
public class ThreadedTest_HelperV2 extends Thread {
ThreadTest_Form myForm;
public ThreadedTest_HelperV2(ThreadTest_Form parent) {
this.myForm = parent;
}
public void run() {
int i = 0;
int fps = 0;
Robot robot = null;
Image screen_capture = null;
Rectangle screen = new
Rectangle(Toolkit.getDefaultToolkit().getScreenSize());
int scaleX =
Toolkit.getDefaultToolkit().getScreenSize().width / 4;
int scaleY =
Toolkit.getDefaultToolkit().getScreenSize().height / 4;
myForm.setSize(scaleX+5, scaleY+25);
long t0 = System.currentTimeMillis();
while (true) {
i++;
long t1 = System.currentTimeMillis();
int seconds = (int) (t1-t0) / 1000;
if (seconds > 1) {
fps = i / seconds;
myForm.setTitle("FPS: " + fps);
}
else
myForm.setTitle("FPS: Analyzing..");
try {
robot = new java.awt.Robot();
screen_capture =
robot.createScreenCapture(screen).getScaledInstance(scaleX, scaleY,
Image.SCALE_FAST);
} catch (AWTException e) {
e.printStackTrace();
System.exit(-1);
}
myForm.jLabel1.setIcon(new ImageIcon(screen_capture));
myForm.jLabel1.update(myForm.jLabel1.getGraphics());
}
}
}
The only real issue I've come up with using this code is that my
jframe/jlabel (can't tell which) flickers a bit. I've read that this
is because you aren't supposed to update swing elements inside a
thread, but I'm still working on separating the logic. Running into
problems with this since I keep getting "non-static blah blah must be
set to static" when trying to modify objects.
Any hints?