add support for images from Rosey Cubesat

src/main/java/ru/r2cloud/jradio/roseycub/ImageChunk.java

@@ -0,0 +1,57 @@
+package ru.r2cloud.jradio.roseycub;
+
+import java.io.DataInputStream;
+import java.io.IOException;
+
+public class ImageChunk {
+
+	private int sequenceId;
+	private boolean isPreview;
+	private int elementId;
+	private byte[] data;
+
+	public ImageChunk() {
+		// do nothing
+	}
+
+	public ImageChunk(DataInputStream dis) throws IOException {
+		sequenceId = dis.readUnsignedShort();
+		isPreview = (dis.readUnsignedByte() > 0);
+		elementId = dis.readUnsignedShort();
+		data = new byte[dis.available()];
+		dis.readFully(data);
+	}
+
+	public int getSequenceId() {
+		return sequenceId;
+	}
+
+	public void setSequenceId(int sequenceId) {
+		this.sequenceId = sequenceId;
+	}
+
+	public boolean isPreview() {
+		return isPreview;
+	}
+
+	public void setPreview(boolean isPreview) {
+		this.isPreview = isPreview;
+	}
+
+	public int getElementId() {
+		return elementId;
+	}
+
+	public void setElementId(int elementId) {
+		this.elementId = elementId;
+	}
+
+	public byte[] getData() {
+		return data;
+	}
+
+	public void setData(byte[] data) {
+		this.data = data;
+	}
+
+}

src/main/java/ru/r2cloud/jradio/roseycub/RoseyCubesatBeacon.java

@@ -12,6 +12,7 @@ public class RoseyCubesatBeacon extends Ax25Beacon {
 	private int payloadTo;
 	private int packetId;
 	private PeriodicMessage message;
+	private ImageChunk imageChunk;
 	private byte[] unknownPayload;
 
 	@Override
@@ -21,12 +22,22 @@ public void readBeacon(DataInputStream dis) throws IOException, UncorrectableExc
 		packetId = dis.readUnsignedShort();
 		if (packetId == 0xFFFF) {
 			message = new PeriodicMessage(dis);
+		} else if (packetId == 0xA40C) {
+			imageChunk = new ImageChunk(dis);
 		} else {
 			unknownPayload = new byte[dis.available()];
 			dis.readFully(unknownPayload);
 		}
 	}
 
+	public ImageChunk getImageChunk() {
+		return imageChunk;
+	}
+
+	public void setImageChunk(ImageChunk imageChunk) {
+		this.imageChunk = imageChunk;
+	}
+
 	public int getPayloadSize() {
 		return payloadSize;
 	}

src/main/java/ru/r2cloud/jradio/roseycub/RoseyPictureDecoder.java

@@ -0,0 +1,170 @@
+package ru.r2cloud.jradio.roseycub;
+
+import java.awt.image.BufferedImage;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.Comparator;
+import java.util.Iterator;
+import java.util.List;
+import java.util.NoSuchElementException;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import ru.r2cloud.jradio.sharjahsat.Sharjahsat1PictureDecoder;
+
+public class RoseyPictureDecoder implements Iterator<BufferedImage> {
+
+	private static final Logger LOG = LoggerFactory.getLogger(Sharjahsat1PictureDecoder.class);
+	private static final int[][] ADJ_INDEXES = new int[][] { { -1, 0 }, { 0, -1 }, { 0, 1 }, { 1, 0 } };
+	private static final int[][] LEFT_RIGHT_INDEXES = new int[][] { { -1, 0 }, { 1, 0 } };
+	private static final int[][] TOP_BOTTOM_INDEXES = new int[][] { { 0, -1 }, { 0, 1 } };
+	private static final int[][] DIAGONAL_INDEXES = new int[][] { { -1, -1 }, { -1, 1 }, { 1, -1 }, { 1, 1 } };
+
+	private final List<RoseyCubesatBeacon> beacons;
+	private List<RoseyCubesatBeacon> currentBatch;
+	private int currentIndex = 0;
+	private boolean isPreview;
+
+	public RoseyPictureDecoder(List<RoseyCubesatBeacon> beacons) {
+		this.beacons = beacons;
+		// make sure packets sorted backwards using packet counter
+		Collections.sort(beacons, new Comparator<RoseyCubesatBeacon>() {
+			@Override
+			public int compare(RoseyCubesatBeacon o1, RoseyCubesatBeacon o2) {
+				if (o2.getImageChunk() == null || o1.getImageChunk() == null) {
+					return 0;
+				}
+				return Long.compare(o1.getImageChunk().getElementId(), o2.getImageChunk().getElementId());
+			}
+		});
+	}
+
+	@Override
+	public boolean hasNext() {
+		if (currentIndex >= beacons.size()) {
+			currentBatch = null;
+			return false;
+		}
+		Integer previousOffset = null;
+		currentBatch = new ArrayList<>();
+		for (; currentIndex < beacons.size(); currentIndex++) {
+			RoseyCubesatBeacon cur = beacons.get(currentIndex);
+			// filter out all non-image beacons
+			if (cur.getImageChunk() == null) {
+				continue;
+			}
+			if (previousOffset == null) {
+				isPreview = cur.getImageChunk().isPreview();
+			}
+			previousOffset = cur.getImageChunk().getElementId();
+			currentBatch.add(cur);
+			if (cur.getImageChunk().isPreview() && previousOffset == 21) {
+				break;
+			}
+			if (!cur.getImageChunk().isPreview() && previousOffset == 2159) {
+				break;
+			}
+		}
+		if (currentBatch.isEmpty()) {
+			currentBatch = null;
+			return false;
+		}
+		return true;
+	}
+
+	@Override
+	public BufferedImage next() {
+		if (currentBatch == null) {
+			throw new NoSuchElementException();
+		}
+		int width;
+		int height;
+		if (isPreview) {
+			width = 48;
+			height = 36;
+		} else {
+			width = 480;
+			height = 360;
+		}
+
+		try {
+			BufferedImage greyScale = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
+			for (RoseyCubesatBeacon cur : currentBatch) {
+				int batchX = (cur.getImageChunk().getElementId() * cur.getImageChunk().getData().length) % width;
+				int batchY = (cur.getImageChunk().getElementId() * cur.getImageChunk().getData().length) / width;
+				for (int i = 0; i < cur.getImageChunk().getData().length; i++) {
+					int x = batchX + i;
+					int y = batchY;
+					if (x >= greyScale.getWidth()) {
+						x = 0;
+						y++;
+					}
+					greyScale.setRGB(x, y, (cur.getImageChunk().getData()[i] & 0xFF));
+				}
+			}
+
+			BufferedImage result = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
+			// bayer convertion
+			// COLOR_BayerGR2RGB
+			for (int i = 0; i < greyScale.getWidth(); i++) {
+				for (int j = 0; j < greyScale.getHeight(); j++) {
+					int row = j % 2;
+					int col = i % 2;
+					int red = 0;
+					int green = 0;
+					int blue = 0;
+					// green
+					if (row == 0 && col == 0) {
+						red = calculatePixelValue(i, j, greyScale, LEFT_RIGHT_INDEXES);
+						green = (greyScale.getRGB(i, j) & 0xFF);
+						blue = calculatePixelValue(i, j, greyScale, TOP_BOTTOM_INDEXES);
+					}
+					// red
+					if (row == 0 && col == 1) {
+						red = (greyScale.getRGB(i, j) & 0xFF);
+						green = calculatePixelValue(i, j, greyScale, ADJ_INDEXES);
+						blue = calculatePixelValue(i, j, greyScale, DIAGONAL_INDEXES);
+					}
+					// blue
+					if (row == 1 && col == 0) {
+						red = calculatePixelValue(i, j, greyScale, DIAGONAL_INDEXES);
+						green = calculatePixelValue(i, j, greyScale, ADJ_INDEXES);
+						blue = (greyScale.getRGB(i, j) & 0xFF);
+					}
+					// green
+					if (row == 1 && col == 1) {
+						red = calculatePixelValue(i, j, greyScale, TOP_BOTTOM_INDEXES);
+						green = (greyScale.getRGB(i, j) & 0xFF);
+						blue = calculatePixelValue(i, j, greyScale, LEFT_RIGHT_INDEXES);
+					}
+					result.setRGB(i, j, (red << 16) | (green << 8) | (blue));
+				}
+			}
+			return result;
+		} catch (Exception e) {
+			LOG.error("unable to create image", e);
+			return null;
+		}
+	}
+
+	private static int calculatePixelValue(int x, int y, BufferedImage image, int[][] indexesToTake) {
+		int total = 0;
+		float sum = 0;
+		for (int index = 0; index < indexesToTake.length; index++) {
+			int[] ind = indexesToTake[index];
+			int expectedX = x + ind[0];
+			int expectedY = y + ind[1];
+			if (expectedX < 0 || expectedX >= image.getWidth()) {
+				continue;
+			}
+			if (expectedY < 0 || expectedY >= image.getHeight()) {
+				continue;
+			}
+			sum += (image.getRGB(expectedX, expectedY) & 0xFF);
+			total++;
+		}
+		return (int) (sum / total);
+	}
+
+}

src/test/java/ru/r2cloud/jradio/roseycub/RoseyCubesatBeaconTest.java

@@ -19,18 +19,27 @@ public void testMessage() throws Exception {
 		result.readBeacon(data);
 		AssertJson.assertObjectsEqual("RoseyCubesatBeacon-message.json", result);
 	}
-
+
+	@Test
+	public void testImageChunk() throws Exception {
+		byte[] data = ViterbiTest.hexStringToByteArray("A49EA68AB262E0A49EA68AB2626303F05701A40C00000006620A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A");
+		RoseyCubesatBeacon result = new RoseyCubesatBeacon();
+		result.readBeacon(data);
+		AssertJson.assertObjectsEqual("RoseyCubesatBeacon-image.json", result);
+	}
+
 	@Test
 	public void testUnknown() throws Exception {
 		byte[] data = ViterbiTest.hexStringToByteArray("A49EA68AB262E0A49EA68AB2626303F00601FA02004F000E");
 		RoseyCubesatBeacon result = new RoseyCubesatBeacon();
 		result.readBeacon(data);
 		AssertJson.assertObjectsEqual("RoseyCubesatBeacon-unknown.json", result);
 	}
-	
+
 	@Test
 	public void testPojo() {
 		assertThat(RoseyCubesatBeacon.class, allOf(hasValidBeanConstructor(), hasValidGettersAndSetters()));
 		assertThat(PeriodicMessage.class, allOf(hasValidBeanConstructor(), hasValidGettersAndSetters()));
 	}
+
 }

src/test/java/ru/r2cloud/jradio/roseycub/RoseyPictureDecoderTest.java

@@ -0,0 +1,35 @@
+package ru.r2cloud.jradio.roseycub;
+
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+
+import java.io.BufferedReader;
+import java.io.InputStreamReader;
+import java.util.ArrayList;
+import java.util.List;
+
+import org.junit.Test;
+
+import ru.r2cloud.jradio.TestUtil;
+import ru.r2cloud.jradio.fec.ViterbiTest;
+
+public class RoseyPictureDecoderTest {
+
+	@Test
+	public void testSuccess() throws Exception {
+		List<RoseyCubesatBeacon> beacons = new ArrayList<>();
+		try (BufferedReader r = new BufferedReader(new InputStreamReader(RoseyPictureDecoderTest.class.getClassLoader().getResourceAsStream("rosey_beacons.txt")))) {
+			String curline = null;
+			while ((curline = r.readLine()) != null) {
+				curline = curline.trim();
+				RoseyCubesatBeacon cur = new RoseyCubesatBeacon();
+				cur.readBeacon(ViterbiTest.hexStringToByteArray(curline));
+				beacons.add(cur);
+			}
+		}
+		RoseyPictureDecoder decoder = new RoseyPictureDecoder(beacons);
+		assertTrue(decoder.hasNext());
+		TestUtil.assertImage("expected/rosey/rosey.png", decoder.next());
+		assertFalse(decoder.hasNext());
+	}
+}