Java tutorial
/******************************************************************************* * Copyright (c) 2015-2019 Skymind, Inc. * * This program and the accompanying materials are made available under the * terms of the Apache License, Version 2.0 which is available at * https://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. * * SPDX-License-Identifier: Apache-2.0 ******************************************************************************/ package org.deeplearning4j.examples.multigpu.video; import org.apache.commons.io.FilenameUtils; import org.jcodec.api.SequenceEncoder; import java.awt.*; import java.awt.geom.Arc2D; import java.awt.geom.Ellipse2D; import java.awt.geom.Line2D; import java.awt.geom.Rectangle2D; import java.awt.image.BufferedImage; import java.io.File; import java.nio.file.Files; import java.nio.file.Paths; import java.nio.file.StandardOpenOption; import java.util.Random; /**A support class for generating a synthetic video data set * Nothing here is specific to DL4J * @author Alex Black */ public class VideoGenerator { public static final int NUM_SHAPES = 4; //0=circle, 1=square, 2=arc, 3=line public static final int MAX_VELOCITY = 3; public static final int SHAPE_SIZE = 25; public static final int SHAPE_MIN_DIST_FROM_EDGE = 15; public static final int DISTRACTOR_MIN_DIST_FROM_EDGE = 0; public static final int LINE_STROKE_WIDTH = 6; //Width of line (line shape only) public static final BasicStroke lineStroke = new BasicStroke(LINE_STROKE_WIDTH); public static final int MIN_FRAMES = 10; //Minimum number of frames the target shape to be present public static final float MAX_NOISE_VALUE = 0.5f; private static int[] generateVideo(String path, int nFrames, int width, int height, int numShapes, Random r, boolean backgroundNoise, int numDistractorsPerFrame) throws Exception { //First: decide where transitions between one shape and another are double[] rns = new double[numShapes]; double sum = 0; for (int i = 0; i < numShapes; i++) { rns[i] = r.nextDouble(); sum += rns[i]; } for (int i = 0; i < numShapes; i++) rns[i] /= sum; int[] startFrames = new int[numShapes]; startFrames[0] = 0; for (int i = 1; i < numShapes; i++) { startFrames[i] = (int) (startFrames[i - 1] + MIN_FRAMES + rns[i] * (nFrames - numShapes * MIN_FRAMES)); } //Randomly generate shape positions, velocities, colors, and type int[] shapeTypes = new int[numShapes]; int[] initialX = new int[numShapes]; int[] initialY = new int[numShapes]; double[] velocityX = new double[numShapes]; double[] velocityY = new double[numShapes]; Color[] color = new Color[numShapes]; for (int i = 0; i < numShapes; i++) { shapeTypes[i] = r.nextInt(NUM_SHAPES); initialX[i] = SHAPE_MIN_DIST_FROM_EDGE + r.nextInt(width - SHAPE_SIZE - 2 * SHAPE_MIN_DIST_FROM_EDGE); initialY[i] = SHAPE_MIN_DIST_FROM_EDGE + r.nextInt(height - SHAPE_SIZE - 2 * SHAPE_MIN_DIST_FROM_EDGE); velocityX[i] = -1 + 2 * r.nextDouble(); velocityY[i] = -1 + 2 * r.nextDouble(); color[i] = new Color(r.nextFloat(), r.nextFloat(), r.nextFloat()); } //Generate a sequence of BufferedImages with the given shapes, and write them to the video SequenceEncoder enc = new SequenceEncoder(new File(path)); int currShape = 0; int[] labels = new int[nFrames]; for (int i = 0; i < nFrames; i++) { if (currShape < numShapes - 1 && i >= startFrames[currShape + 1]) currShape++; BufferedImage bi = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB); Graphics2D g2d = bi.createGraphics(); g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON); g2d.setBackground(Color.BLACK); if (backgroundNoise) { for (int x = 0; x < width; x++) { for (int y = 0; y < height; y++) { bi.setRGB(x, y, new Color(r.nextFloat() * MAX_NOISE_VALUE, r.nextFloat() * MAX_NOISE_VALUE, r.nextFloat() * MAX_NOISE_VALUE).getRGB()); } } } g2d.setColor(color[currShape]); //Position of shape this frame int currX = (int) (initialX[currShape] + (i - startFrames[currShape]) * velocityX[currShape] * MAX_VELOCITY); int currY = (int) (initialY[currShape] + (i - startFrames[currShape]) * velocityY[currShape] * MAX_VELOCITY); //Render the shape switch (shapeTypes[currShape]) { case 0: //Circle g2d.fill(new Ellipse2D.Double(currX, currY, SHAPE_SIZE, SHAPE_SIZE)); break; case 1: //Square g2d.fill(new Rectangle2D.Double(currX, currY, SHAPE_SIZE, SHAPE_SIZE)); break; case 2: //Arc g2d.fill(new Arc2D.Double(currX, currY, SHAPE_SIZE, SHAPE_SIZE, 315, 225, Arc2D.PIE)); break; case 3: //Line g2d.setStroke(lineStroke); g2d.draw(new Line2D.Double(currX, currY, currX + SHAPE_SIZE, currY + SHAPE_SIZE)); break; default: throw new RuntimeException(); } //Add some distractor shapes, which are present for one frame only for (int j = 0; j < numDistractorsPerFrame; j++) { int distractorShapeIdx = r.nextInt(NUM_SHAPES); int distractorX = DISTRACTOR_MIN_DIST_FROM_EDGE + r.nextInt(width - SHAPE_SIZE); int distractorY = DISTRACTOR_MIN_DIST_FROM_EDGE + r.nextInt(height - SHAPE_SIZE); g2d.setColor(new Color(r.nextFloat(), r.nextFloat(), r.nextFloat())); switch (distractorShapeIdx) { case 0: g2d.fill(new Ellipse2D.Double(distractorX, distractorY, SHAPE_SIZE, SHAPE_SIZE)); break; case 1: g2d.fill(new Rectangle2D.Double(distractorX, distractorY, SHAPE_SIZE, SHAPE_SIZE)); break; case 2: g2d.fill(new Arc2D.Double(distractorX, distractorY, SHAPE_SIZE, SHAPE_SIZE, 315, 225, Arc2D.PIE)); break; case 3: g2d.setStroke(lineStroke); g2d.draw(new Line2D.Double(distractorX, distractorY, distractorX + SHAPE_SIZE, distractorY + SHAPE_SIZE)); break; default: throw new RuntimeException(); } } enc.encodeImage(bi); g2d.dispose(); labels[i] = shapeTypes[currShape]; } enc.finish(); //write .mp4 return labels; } public static void generateVideoData(String outputFolder, String filePrefix, int nVideos, int nFrames, int width, int height, int numShapesPerVideo, boolean backgroundNoise, int numDistractorsPerFrame, long seed) throws Exception { Random r = new Random(seed); for (int i = 0; i < nVideos; i++) { String videoPath = FilenameUtils.concat(outputFolder, filePrefix + "_" + i + ".mp4"); String labelsPath = FilenameUtils.concat(outputFolder, filePrefix + "_" + i + ".txt"); int[] labels = generateVideo(videoPath, nFrames, width, height, numShapesPerVideo, r, backgroundNoise, numDistractorsPerFrame); //Write labels to text file StringBuilder sb = new StringBuilder(); for (int j = 0; j < labels.length; j++) { sb.append(labels[j]); if (j != labels.length - 1) sb.append("\n"); } Files.write(Paths.get(labelsPath), sb.toString().getBytes("utf-8"), StandardOpenOption.CREATE, StandardOpenOption.TRUNCATE_EXISTING); } } }