Java Code Examples for ucar.ma2.DataType#unsignedByteToShort()

public static double entropy(byte[] data) {
  int[] p = new int[256];

  // count occurrences
  for (byte b : data) {
    short s = DataType.unsignedByteToShort(b);
    p[s]++;
  }

  double n = data.length;
  double iln2 = 1.0 / Math.log(2.0);
  double sum = 0.0;
  for (int i = 0; i < 256; i++) {
    if (p[i] == 0)
      continue;
    double prob = ((double) p[i]) / n;
    sum += Math.log(prob) * prob * iln2;
  }

  return (sum == 0) ? 0.0 : -sum;
}
 

protected Array convertEnums(Map<Integer, String> map, DataType dataType, Array values) {
  Array result = Array.factory(DataType.STRING, values.getShape());
  IndexIterator ii = result.getIndexIterator();
  values.resetLocalIterator();
  while (values.hasNext()) {
    int ival;
    if (dataType == DataType.ENUM1)
      ival = (int) DataType.unsignedByteToShort(values.nextByte());
    else if (dataType == DataType.ENUM2)
      ival = DataType.unsignedShortToInt(values.nextShort());
    else
      ival = values.nextInt();
    String sval = map.get(ival);
    if (sval == null)
      sval = "Unknown enum value=" + ival;
    ii.setObjectNext(sval);
  }
  return result;
}
 

@Override
public long readVariableSizeUnsigned(int size) throws IOException {
  long vv;
  if (size == 1) {
    vv = DataType.unsignedByteToShort(raf.readByte());
  } else if (size == 2) {
    if (debugPos) {
      log.debug("position={}", raf.getFilePointer());
    }
    short s = raf.readShort();
    vv = DataType.unsignedShortToInt(s);
  } else if (size == 4) {
    vv = DataType.unsignedIntToLong(raf.readInt());
  } else if (size == 8) {
    vv = raf.readLong();
  } else {
    vv = readVariableSizeN(size);
  }
  return vv;
}
 

void showBitmap(Grib1RecordBean bean1, Formatter f) throws IOException {
  byte[] bitmap;
  try (ucar.unidata.io.RandomAccessFile raf = bean1.getRaf()) {
    Grib1SectionBitMap bms = bean1.gr.getBitMapSection();
    f.format("%s%n", bms);
    bitmap = bms.getBitmap(raf);
  }

  if (bitmap == null) {
    f.format(" no bitmap%n");
    return;
  }

  int count = 0;
  int bits = 0;
  for (byte b : bitmap) {
    short s = DataType.unsignedByteToShort(b);
    bits += Long.bitCount(s);
    f.format("%8s", Long.toBinaryString(s));
    if (++count % 10 == 0)
      f.format("%n");
  }
  f.format("%n%n#bits on = %d%n", bits);
  f.format("bitmap size = %d%n", 8 * count);
}
 

void showBitmap(Grib2RecordBean bean1, Formatter f) throws IOException {
  byte[] bitmap;
  try (ucar.unidata.io.RandomAccessFile raf = bean1.getRaf()) {
    Grib2SectionBitMap bms = bean1.gr.getBitmapSection();
    f.format("%s%n", bms);
    bitmap = bms.getBitmap(raf);
  }

  if (bitmap == null) {
    f.format(" no bitmap%n");
    return;
  }

  int count = 0;
  int bits = 0;
  for (byte b : bitmap) {
    short s = DataType.unsignedByteToShort(b);
    bits += Long.bitCount(s);
    f.format("%8s", Long.toBinaryString(s));
    if (++count % 10 == 0)
      f.format("%n");
  }
  f.format("%n%n#bits on = %d%n", bits);
  f.format("total nbits = %d%n", 8 * count);
  f.format("bitmap nbytes = %d%n", bitmap.length);
}
 

private double readScaledInt(ByteBuffer buf) {
  // Get the first two bytes
  short s1 = buf.getShort();

  // And the last one as unsigned
  short s2 = DataType.unsignedByteToShort(buf.get());

  // Get the sign bit, converting from 0 or 2 to +/- 1.
  int posneg = 1 - ((s1 & 0x8000) >> 14);

  // Combine the first two bytes (without sign bit) with the last byte.
  // Multiply by proper factor for +/-
  int nn = (((s1 & 0x7FFF) << 8) | s2) * posneg;
  return (double) nn / 10000.0;
}
 

public static int countBits(byte[] bitmap) {
  int bits = 0;
  for (byte b : bitmap) {
    short s = DataType.unsignedByteToShort(b);
    bits += Long.bitCount(s);
  }
  return bits;
}
 

public void toRawGdsString(Formatter f) {
  byte[] bytes = gds.getRawBytes();
  int count = 1;
  for (byte b : bytes) {
    short s = DataType.unsignedByteToShort(b);
    f.format(" %d : %d%n", count++, s);
  }
}
 

public void toRawPdsString(Formatter f) {
  byte[] bytes = gr.getPDSsection().getRawBytes();
  int count = 1;
  for (byte b : bytes) {
    short s = DataType.unsignedByteToShort(b);
    f.format(" %d : %d%n", count++, s);
  }
}
 

public void toRawPdsString(Formatter f) {
  byte[] bytes = gr.getPDSsection().getRawBytes();
  int count = 1;
  for (byte b : bytes) {
    short s = DataType.unsignedByteToShort(b);
    f.format(" %d : %d%n", count++, s);
  }
}
 

public void toRawGdsString(Formatter f) {
  byte[] bytes = gds.getRawBytes();
  int count = 1;
  for (byte b : bytes) {
    short s = DataType.unsignedByteToShort(b);
    f.format(" %d : %d%n", count++, s);
  }
}
 

public static String showBits(byte[] bytes) {
  try (Formatter f = new Formatter()) {
    int count = 0;
    for (byte b : bytes) {
      short s = DataType.unsignedByteToShort(b);
      f.format("%8s", Long.toBinaryString(s));
      if (++count % 10 == 0)
        f.format("%n");
    }
    return f.toString();
  }
}
 

public byte[] convert(String srcPath, double a, double b) throws IOException {
  try (NetcdfFile ncfile = NetcdfFiles.open(srcPath)) {
    Variable v = ncfile.findVariable("image1/image_data");
    Array array = v.read();

    int[] cmap = new int[256]; // palette
    cmap[0] = 0x00FFFFFF; // transparent and white
    for (int i = 1; i != 256; i++) {
      // 1 to 255 renders as (almost) white to black
      cmap[i] = 0xFF000000 | ((0xFF - i) * 0x010101);
    }
    IndexColorModel colorModel =
        new IndexColorModel(8, cmap.length, cmap, 0, true, Transparency.OPAQUE, DataBuffer.TYPE_BYTE);

    int[] shape = array.getShape();
    BufferedImage bi = new BufferedImage(shape[1], shape[0], BufferedImage.TYPE_BYTE_INDEXED, colorModel);

    Index index = array.getIndex();
    for (int y = 0; y < shape[0]; y++) {
      for (int x = 0; x < shape[1]; x++) {
        index.set(y, x);

        byte bval = array.getByte(index);
        double dval = v.getDataType().isUnsigned() ? (double) DataType.unsignedByteToShort(bval) : (double) bval;

        // double dval = array.getDouble(index);
        // Fix for NetCDF returning all values larger than 127 as (value - 256):
        // if (dval < -1) {
        // dval += 256;
        // }
        int pval = (int) Math.round(a * dval + b);
        pval = Math.min(Math.max(pval, 0), 255);
        bi.getRaster().setSample(x, y, 0, pval);
      }
    }

    ByteArrayOutputStream os = new ByteArrayOutputStream();
    ImageIO.write(bi, "png", os);
    return os.toByteArray();
  }
}
 

private int makeUnsignedIntFromBytes(byte upper, byte lower) {
  return DataType.unsignedByteToShort(upper) * 256 + DataType.unsignedByteToShort(lower);
}
 

int[] getCalibrationInfo(ByteBuffer bos, int phys_elem, int ent_id) {

    bos.position(46);
    byte nv = bos.get(); /* Cal indicator */
    int navcal = DataType.unsignedByteToShort(nv);
    int[] calcods = null;
    if (navcal == 128) { /* Unidata Cal block found; unpack values */
      int scale = 10000;
      int jscale = 100000000;
      byte[] unsb = new byte[8];
      bos.get(unsb);
      bos.position(55);
      nv = bos.get();
      int calcod = DataType.unsignedByteToShort(nv);

      if (calcod > 0) {
        calcods = new int[5 * calcod + 1];
        calcods[0] = calcod;
        for (int i = 0; i < calcod; i++) {

          bos.position(56 + i * 16);
          int minb = bos.getInt() / 10000; /* min brightness values */
          int maxb = bos.getInt() / 10000; /* max brightness values */
          int mind = bos.getInt(); /* min data values */
          int maxd = bos.getInt(); /* max data values */

          int idscal = 1;
          while (mind % idscal == 0 && maxd % idscal == 0) {
            idscal *= 10;
          }
          idscal /= 10;

          if (idscal < jscale)
            jscale = idscal;

          calcods[1 + i * 5] = mind;
          calcods[2 + i * 5] = maxd;
          calcods[3 + i * 5] = minb;
          calcods[4 + i * 5] = maxb;
          calcods[5 + i * 5] = 0;

        }

        if (jscale > scale)
          jscale = scale;
        scale /= jscale;

        if (gini_GetPhysElemID(phys_elem, ent_id).contains("Precipitation")) {
          if (scale < 100) {
            jscale /= (100 / scale);
            scale = 100;
          }
        }

        for (int i = 0; i < calcod; i++) {
          calcods[1 + i * 5] /= jscale;
          calcods[2 + i * 5] /= jscale;
          calcods[5 + i * 5] = scale;
        }

      }

    }

    return calcods;
  }
 

@Test
public void testConvertUnsigned() {
  int val = (int) DataType.unsignedByteToShort((byte) -200);
  int val2 = DataType.unsignedShortToInt((short) -200);
  assertNotEquals(val, val2);
}
 

/**
 * Convert unsigned bytes into an integer.
 *
 * @param raf read one byte from here
 * @return integer value
 * @throws IOException on read error
 */
public static int uint(RandomAccessFile raf) throws IOException {
  int a = raf.read();
  return (int) DataType.unsignedByteToShort((byte) a);
}