What is the best method to capture images from a live video device for use by a Java-based application?

Question

I am looking into an image processing problem for semi-real time detection of certain scenarios. My goal is to have the live video arrive as Motion JPEG frames in my Java code somehow.

I am familiar with the Java Media Framework and, sadly, I think we can consider that an effectively dead API. I am also familiar with Axis boxes and, while I really like their solution, I would appreciate any critical feedback on my specific points of interest.

This is how I define "best" for the purpose of this discussion:

• Latency - if I'm controlling the camera using this video stream, I would like to keep my round-trip latency at less than 100 milliseconds if possible. That's measured as the time between my control input to the time when I see the visible change. EDIT some time later: another thing to keep in mind is that camera control is likely to be a combination of manual and automatic (event triggers). We need to see those pictures right away, even if the high quality feed is archived separately.
• Cost - free / open source is better than not free.
• Adjustable codec parameters - I need to be able to tune the codec for certain situations. Sometimes a high-speed low-resolution stream is actually easier to process.
• "Integration" with Java - how much trouble is it to hook this solution to my code? Am I sending packets over a socket? Hitting URLs? Installing Direct3D / JNI combinations?
• Windows / Linux / both? - I would prefer an operating system agnostic solution because I have to deliver to several flavors of OS but there may be a solution that is optimal for one but not the other.

NOTE: I am aware of other image / video capture codecs and that is not the focus of this question. I am specifically not interested in streaming APIs (e.g., MPEG4) due to the loss of frame accuracy. However, if there is a solution to my question that delivers another frame-accurate data stream, please chime in.

Follow-up to this question: at this point, I am strongly inclined to buy appliances such as the Axis video encoders rather than trying to capture the video in software or on the PC directly. However, if someone has alternatives, I'd love to hear them.

Answer 1

This JavaCV implementation works fine.

CODE:

import com.googlecode.javacv.OpenCVFrameGrabber;

import com.googlecode.javacv.cpp.opencv_core.IplImage;
import static com.googlecode.javacv.cpp.opencv_highgui.*;

public class CaptureImage {
    private static void captureFrame() {
        // 0-default camera, 1 - next...so on
        final OpenCVFrameGrabber grabber = new OpenCVFrameGrabber(0);
        try {
            grabber.start();
            IplImage img = grabber.grab();
            if (img != null) {
                cvSaveImage("capture.jpg", img);
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
    public static void main(String[] args) {
        captureFrame();
    }
}

There is also post on viewing live video from Camera .And configuration for JavaCV :

I think this will meet your requirements.