ExampleVideoMosaic.java

/*
 * Copyright (c) 2011-2013, Peter Abeles. All Rights Reserved.
 *
 * This file is part of BoofCV (http://boofcv.org).
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package boofcv.examples.geometry;

import boofcv.abst.feature.detect.interest.ConfigGeneralDetector;
import boofcv.abst.feature.tracker.PointTracker;
import boofcv.abst.sfm.d2.ImageMotion2D;
import boofcv.abst.sfm.d2.MsToGrayMotion2D;
import boofcv.alg.sfm.d2.StitchingFromMotion2D;
import boofcv.core.image.ConvertBufferedImage;
import boofcv.factory.feature.tracker.FactoryPointTracker;
import boofcv.factory.sfm.FactoryMotion2D;
import boofcv.gui.image.ImageGridPanel;
import boofcv.gui.image.ShowImages;
import boofcv.io.MediaManager;
import boofcv.io.image.SimpleImageSequence;
import boofcv.io.wrapper.DefaultMediaManager;
import boofcv.misc.BoofMiscOps;
import boofcv.struct.image.ImageFloat32;
import boofcv.struct.image.ImageType;
import boofcv.struct.image.MultiSpectral;
import georegression.struct.homo.Homography2D_F64;
import georegression.struct.point.Point2D_F64;

import java.awt.image.BufferedImage;

/**
 * Example of how to create a mosaic from a video sequence using StitchingFromMotion2D.  Mosaics work best
 * when the scene being observed is far away or a flat surface.  The camera motion should typically be rotational only,
 * but translation can work depending on the scene's geometry.  Motion blur and cheap cameras in general will degrade
 * performance significantly with the current algorithm.  This example just demonstrates a gray scale image, but
 * with additional work color images can also be processed.
 *
 * @author Peter Abeles
 */
public class ExampleVideoMosaic {
	public static void main( String args[] ) {

		// Configure the feature detector
		ConfigGeneralDetector confDetector = new ConfigGeneralDetector();
		confDetector.threshold = 10;
		confDetector.maxFeatures = 300;
		confDetector.radius = 2;

		// Use a KLT tracker
		PointTracker<ImageFloat32> tracker = FactoryPointTracker.klt(new int[]{1,2,4,8},confDetector,3,
				ImageFloat32.class,ImageFloat32.class);

		// This estimates the 2D image motion
		// An Affine2D_F64 model also works quite well.
		ImageMotion2D<ImageFloat32,Homography2D_F64> motion2D =
				FactoryMotion2D.createMotion2D(200,3,2,30,0.6,0.5,false,tracker,new Homography2D_F64());

		// wrap it so it output color images while estimating motion from gray
		ImageMotion2D<MultiSpectral<ImageFloat32>,Homography2D_F64> motion2DColor =
				new MsToGrayMotion2D<ImageFloat32,Homography2D_F64>(motion2D,ImageFloat32.class);

		// This fuses the images together
		StitchingFromMotion2D<MultiSpectral<ImageFloat32>,Homography2D_F64>
				stitch = FactoryMotion2D.createVideoStitchMS(0.5, motion2DColor, ImageFloat32.class);

		// Load an image sequence
		MediaManager media = DefaultMediaManager.INSTANCE;
		String fileName = "../data/applet/shake.mjpeg";
		SimpleImageSequence<MultiSpectral<ImageFloat32>> video =
				media.openVideo(fileName, ImageType.ms(3, ImageFloat32.class));

		MultiSpectral<ImageFloat32> frame = video.next();

		// shrink the input image and center it
		Homography2D_F64 shrink = new Homography2D_F64(0.5,0,frame.width/3,0,0.5,frame.height/2,0,0,1);
		shrink = shrink.invert(null);

		// The mosaic will be larger in terms of pixels but the image will be scaled down.
		// To change this into stabilization just make it the same size as the input with no shrink.
		stitch.configure(frame.width,frame.height,null);
		// process the first frame
		stitch.process(frame);

		// Create the GUI for displaying the results + input image
		ImageGridPanel gui = new ImageGridPanel(1,2);
		gui.setImage(0,0,new BufferedImage(frame.width,frame.height,BufferedImage.TYPE_INT_RGB));
		gui.setImage(0,1,new BufferedImage(frame.width,frame.height,BufferedImage.TYPE_INT_RGB));
		gui.autoSetPreferredSize();

		ShowImages.showWindow(gui,"Example Mosaic");

		// process the video sequence one frame at a time
		while( video.hasNext() ) {
			frame = video.next();
			stitch.process(frame);

			// if the current image is close to the image border recenter the mosaic
			StitchingFromMotion2D.Corners corners = stitch.getImageCorners(frame.width,frame.height,null);
			if( nearBorder(corners.p0,stitch) || nearBorder(corners.p1,stitch) ||
					nearBorder(corners.p2,stitch) || nearBorder(corners.p3,stitch) ) {
				stitch.setOriginToCurrent();
			}

			// display the mosaic
			ConvertBufferedImage.convertTo(frame,gui.getImage(0, 0),true);
			ConvertBufferedImage.convertTo(stitch.getStitchedImage(), gui.getImage(0, 1),true);

			gui.repaint();

			// throttle the speed just in case it's on a fast computer
			BoofMiscOps.pause(50);
		}
	}

	/**
	 * Checks to see if the point is near the image border
	 */
	private static boolean nearBorder( Point2D_F64 p , StitchingFromMotion2D<?,?> stitch ) {
		int r = 10;
		if( p.x < r || p.y < r )
			return true;
		if( p.x >= stitch.getStitchedImage().width-r )
			return true;
		if( p.y >= stitch.getStitchedImage().height-r )
			return true;

		return false;
	}
}