boofcv.alg.background.moving.BackgroundMovingBasic_IL Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of feature Show documentation
BoofCV is an open source Java library for real-time computer vision and robotics applications.
There is a newer version: 0.26
/*
 * Copyright (c) 2011-2016, 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.alg.background.moving;

import boofcv.alg.interpolate.InterpolatePixelMB;
import boofcv.alg.interpolate.TypeInterpolate;
import boofcv.alg.misc.GImageMiscOps;
import boofcv.core.image.FactoryGImageMultiBand;
import boofcv.core.image.GImageMultiBand;
import boofcv.core.image.border.BorderType;
import boofcv.factory.interpolate.FactoryInterpolation;
import boofcv.struct.distort.PointTransformModel_F32;
import boofcv.struct.image.*;
import georegression.struct.InvertibleTransform;

/**
 * Implementation of {@link BackgroundMovingBasic} for {@link Planar}.
 *
 * @author Peter Abeles
 */
public class BackgroundMovingBasic_IL>
	extends BackgroundMovingBasic
{
	// where the background image is stored
	protected InterleavedF32 background;
	// interpolates the input image
	protected InterpolatePixelMB interpolationInput;
	// interpolates the background image
	protected InterpolatePixelMB interpolationBG;

	// wrappers which provide abstraction across image types
	protected GImageMultiBand inputWrapper;
	// storage for multi-band pixel values
	protected float[] pixelInput;
	protected float[] pixelBack;

	public BackgroundMovingBasic_IL(float learnRate, float threshold,
									PointTransformModel_F32 transform,
									TypeInterpolate interpType,
									ImageType imageType) {
		super(learnRate, threshold,transform, imageType);

		this.interpolationInput = FactoryInterpolation.createPixelMB(0, 255, interpType,BorderType.EXTENDED,imageType);

		int numBands = imageType.getNumBands();
		background = new InterleavedF32(1,1,numBands);

		this.interpolationBG = FactoryInterpolation.createPixelMB(
				0, 255, interpType, BorderType.EXTENDED, ImageType.il(numBands, InterleavedF32.class));
		this.interpolationBG.setImage(background);

		pixelInput = new float[numBands];
		pixelBack = new float[numBands];

		inputWrapper = FactoryGImageMultiBand.create(imageType);
	}

	/**
	 * Returns the background image.  Pixels which haven't been assigned yet are marked with {@link Float#MAX_VALUE}.
	 *
	 * @return background image.
	 */
	public InterleavedF32 getBackground() {
		return background;
	}

	@Override
	public void initialize(int backgroundWidth, int backgroundHeight, Motion homeToWorld) {
		background.reshape(backgroundWidth,backgroundHeight);
		GImageMiscOps.fill(background, Float.MAX_VALUE);

		this.homeToWorld.set(homeToWorld);
		this.homeToWorld.invert(worldToHome);

		this.backgroundWidth = backgroundWidth;
		this.backgroundHeight = backgroundHeight;
	}

	@Override
	public void reset() {
		GImageMiscOps.fill(background,Float.MAX_VALUE);
	}

	@Override
	protected void updateBackground(int x0, int y0, int x1, int y1, T frame) {

		transform.setModel(worldToCurrent);
		interpolationInput.setImage(frame);

		final int numBands = frame.getNumBands();
		float minusLearn = 1.0f - learnRate;

		for (int y = y0; y < y1; y++) {
			int indexBG = background.startIndex + y*background.stride + x0*numBands;
			for (int x = x0; x < x1; x++ ) {
				transform.compute(x,y,work);

				if( work.x >= 0 && work.x < frame.width && work.y >= 0 && work.y < frame.height) {

					interpolationInput.get(work.x, work.y, pixelInput);

					for (int band = 0; band < numBands; band++, indexBG++) {

						float value = pixelInput[band];
						float bg = background.data[indexBG];

						if( bg == Float.MAX_VALUE ) {
							background.data[indexBG] = value;
						} else {
							background.data[indexBG] = minusLearn*bg + learnRate*value;
						}
					}
				} else {
					indexBG += numBands;
				}
			}
		}
	}

	@Override
	protected void _segment(Motion currentToWorld, T frame, GrayU8 segmented) {
		transform.setModel(currentToWorld);
		inputWrapper.wrap(frame);

		int numBands = background.getNumBands();

		float thresholdSq = numBands*threshold*threshold;

		for (int y = 0; y < frame.height; y++) {
			int indexFrame = frame.startIndex + y*frame.stride;
			int indexSegmented = segmented.startIndex + y*segmented.stride;

			for (int x = 0; x < frame.width; x++, indexFrame += numBands , indexSegmented++ ) {
				transform.compute(x,y,work);

				escapeIf:
				if( work.x >= 0 && work.x < background.width && work.y >= 0 && work.y < background.height) {

					interpolationBG.get(work.x,work.y,pixelBack);

					double sumErrorSq = 0;
					for (int band = 0; band < numBands; band++) {
						float bg = pixelBack[band];
						float pixelFrame = inputWrapper.getF(indexFrame + band);

						if( bg == Float.MAX_VALUE ) {
							segmented.data[indexSegmented] = unknownValue;
							break escapeIf;
						} else {
							float diff = bg - pixelFrame;
							sumErrorSq += diff*diff;
						}
					}

					if ( sumErrorSq <= thresholdSq) {
						segmented.data[indexSegmented] = 0;
					} else {
						segmented.data[indexSegmented] = 1;
					}
				} else {
					// there is no background here.  Just mark it as not moving to avoid false positives
					segmented.data[indexSegmented] = unknownValue;
				}
			}
		}
	}


}