예제 #1
0
  /**
   * Calculates the parameters of the SubbandAn objects that depend on the Quantizer. The 'stepWMSE'
   * field is calculated for each subband which is a leaf in the tree rooted at 'sb', for the
   * specified component. The subband tree 'sb' must be the one for the component 'n'.
   *
   * @param sb The root of the subband tree.
   * @param c The component index
   * @see SubbandAn#stepWMSE
   */
  protected void calcSbParams(SubbandAn sb, int c) {
    float baseStep;

    if (sb.stepWMSE > 0f) // parameters already calculated
    return;
    if (!sb.isNode) {
      if (isReversible(tIdx, c)) {
        sb.stepWMSE = (float) Math.pow(2, -(src.getNomRangeBits(c) << 1)) * sb.l2Norm * sb.l2Norm;
      } else {
        baseStep = ((Float) qsss.getTileCompVal(tIdx, c)).floatValue();
        if (isDerived(tIdx, c)) {
          sb.stepWMSE =
              baseStep
                  * baseStep
                  * (float) Math.pow(2, (sb.anGainExp - sb.level) << 1)
                  * sb.l2Norm
                  * sb.l2Norm;
        } else {
          sb.stepWMSE = baseStep * baseStep;
        }
      }
    } else {
      calcSbParams((SubbandAn) sb.getLL(), c);
      calcSbParams((SubbandAn) sb.getHL(), c);
      calcSbParams((SubbandAn) sb.getLH(), c);
      calcSbParams((SubbandAn) sb.getHH(), c);
      sb.stepWMSE = 1f; // Signal that we already calculated this branch
    }
  }
예제 #2
0
  /**
   * Returns the maximum number of magnitude bits in any subband in the given tile-component if
   * derived quantization is used
   *
   * @param sb The root of the subband tree of the tile-component
   * @param t Tile index
   * @param c Component index
   * @return The highest number of magnitude bit-planes
   */
  private int getMaxMagBitsDerived(Subband sb, int t, int c) {
    int tmp, max = 0;
    int g = ((Integer) gbs.getTileCompVal(t, c)).intValue();

    if (!sb.isNode) {
      float baseStep = ((Float) qsss.getTileCompVal(t, c)).floatValue();
      return g - 1 + sb.level - (int) Math.floor(Math.log(baseStep) / log2);
    }

    max = getMaxMagBitsDerived(sb.getLL(), t, c);
    tmp = getMaxMagBitsDerived(sb.getLH(), t, c);
    if (tmp > max) max = tmp;
    tmp = getMaxMagBitsDerived(sb.getHL(), t, c);
    if (tmp > max) max = tmp;
    tmp = getMaxMagBitsDerived(sb.getHH(), t, c);
    if (tmp > max) max = tmp;

    return max;
  }
예제 #3
0
  /**
   * Returns the maximum number of magnitude bits in any subband in the given tile-component if
   * expounded quantization is used
   *
   * @param sb The root of the subband tree of the tile-component
   * @param t Tile index
   * @param c Component index
   * @return The highest number of magnitude bit-planes
   */
  private int getMaxMagBitsExpounded(Subband sb, int t, int c) {
    int tmp, max = 0;
    int g = ((Integer) gbs.getTileCompVal(t, c)).intValue();

    if (!sb.isNode) {
      float baseStep = ((Float) qsss.getTileCompVal(t, c)).floatValue();
      return g
          - 1
          - (int)
              Math.floor(
                  Math.log(baseStep / (((SubbandAn) sb).l2Norm * (1 << sb.anGainExp))) / log2);
    }

    max = getMaxMagBitsExpounded(sb.getLL(), t, c);
    tmp = getMaxMagBitsExpounded(sb.getLH(), t, c);
    if (tmp > max) max = tmp;
    tmp = getMaxMagBitsExpounded(sb.getHL(), t, c);
    if (tmp > max) max = tmp;
    tmp = getMaxMagBitsExpounded(sb.getHH(), t, c);
    if (tmp > max) max = tmp;

    return max;
  }
예제 #4
0
  /**
   * Returns the next code-block in the current tile for the specified component. The order in which
   * code-blocks are returned is not specified. However each code-block is returned only once and
   * all code-blocks will be returned if the method is called 'N' times, where 'N' is the number of
   * code-blocks in the tile. After all the code-blocks have been returned for the current tile
   * calls to this method will return 'null'.
   *
   * <p>When changing the current tile (through 'setTile()' or 'nextTile()') this method will always
   * return the first code-block, as if this method was never called before for the new current
   * tile.
   *
   * <p>The data returned by this method can be the data in the internal buffer of this object, if
   * any, and thus can not be modified by the caller. The 'offset' and 'scanw' of the returned data
   * can be arbitrary. See the 'CBlkWTData' class.
   *
   * <p>The 'ulx' and 'uly' members of the returned 'CBlkWTData' object contain the coordinates of
   * the top-left corner of the block, with respect to the tile, not the subband.
   *
   * @param c The component for which to return the next code-block.
   * @param cblk If non-null this object will be used to return the new code-block. If null a new
   *     one will be allocated and returned. If the "data" array of the object is non-null it will
   *     be reused, if possible, to return the data.
   * @return The next code-block in the current tile for component 'n', or null if all code-blocks
   *     for the current tile have been returned.
   * @see CBlkWTData
   */
  public final CBlkWTData getNextInternCodeBlock(int c, CBlkWTData cblk) {
    // NOTE: this method is declared final since getNextCodeBlock() relies
    // on this particular implementation
    int k, j;
    int tmp, shiftBits, jmin;
    int w, h;
    int outarr[];
    float infarr[] = null;
    CBlkWTDataFloat infblk;
    float invstep; // The inverse of the quantization step size
    boolean intq; // flag for quantizig ints
    SubbandAn sb;
    float stepUDR; // The quantization step size (for a dynamic
    // range of 1, or unit)
    int g = ((Integer) gbs.getTileCompVal(tIdx, c)).intValue();

    // Are we quantizing ints or floats?
    intq = (src.getDataType(tIdx, c) == DataBlk.TYPE_INT);

    // Check that we have an output object
    if (cblk == null) {
      cblk = new CBlkWTDataInt();
    }

    // Cache input float code-block
    infblk = this.infblk;

    // Get data to quantize. When quantizing int data 'cblk' is used to
    // get the data to quantize and to return the quantized data as well,
    // that's why 'getNextCodeBlock()' is used. This can not be done when
    // quantizing float data because of the different data types, that's
    // why 'getNextInternCodeBlock()' is used in that case.
    if (intq) { // Source data is int
      cblk = src.getNextCodeBlock(c, cblk);
      if (cblk == null) {
        return null; // No more code-blocks in current tile for comp.
      }
      // Input and output arrays are the same (for "in place" quant.)
      outarr = (int[]) cblk.getData();
    } else { // Source data is float
      // Can not use 'cblk' to get float data, use 'infblk'
      infblk = (CBlkWTDataFloat) src.getNextInternCodeBlock(c, infblk);
      if (infblk == null) {
        // Release buffer from infblk: this enables to garbage collect
        // the big buffer when we are done with last code-block of
        // component.
        this.infblk.setData(null);
        return null; // No more code-blocks in current tile for comp.
      }
      this.infblk = infblk; // Save local cache
      infarr = (float[]) infblk.getData();
      // Get output data array and check that there is memory to put the
      // quantized coeffs in
      outarr = (int[]) cblk.getData();
      if (outarr == null || outarr.length < infblk.w * infblk.h) {
        outarr = new int[infblk.w * infblk.h];
        cblk.setData(outarr);
      }
      cblk.m = infblk.m;
      cblk.n = infblk.n;
      cblk.sb = infblk.sb;
      cblk.ulx = infblk.ulx;
      cblk.uly = infblk.uly;
      cblk.w = infblk.w;
      cblk.h = infblk.h;
      cblk.wmseScaling = infblk.wmseScaling;
      cblk.offset = 0;
      cblk.scanw = cblk.w;
    }

    // Cache width, height and subband of code-block
    w = cblk.w;
    h = cblk.h;
    sb = cblk.sb;

    if (isReversible(tIdx, c)) { // Reversible only for int data
      cblk.magbits = g - 1 + src.getNomRangeBits(c) + sb.anGainExp;
      shiftBits = 31 - cblk.magbits;

      // Update the convertFactor field
      cblk.convertFactor = (1 << shiftBits);

      // Since we used getNextCodeBlock() to get the int data then
      // 'offset' is 0 and 'scanw' is the width of the code-block The
      // input and output arrays are the same (i.e. "in place")
      for (j = w * h - 1; j >= 0; j--) {
        tmp = (outarr[j] << shiftBits);
        outarr[j] = ((tmp < 0) ? (1 << 31) | (-tmp) : tmp);
      }
    } else { // Non-reversible, use step size
      float baseStep = ((Float) qsss.getTileCompVal(tIdx, c)).floatValue();

      // Calculate magnitude bits and quantization step size
      if (isDerived(tIdx, c)) {
        cblk.magbits = g - 1 + sb.level - (int) Math.floor(Math.log(baseStep) / log2);
        stepUDR = baseStep / (1 << sb.level);
      } else {
        cblk.magbits =
            g - 1 - (int) Math.floor(Math.log(baseStep / (sb.l2Norm * (1 << sb.anGainExp))) / log2);
        stepUDR = baseStep / (sb.l2Norm * (1 << sb.anGainExp));
      }
      shiftBits = 31 - cblk.magbits;
      // Calculate step that decoder will get and use that one.
      stepUDR = convertFromExpMantissa(convertToExpMantissa(stepUDR));
      invstep = 1.0f / ((1L << (src.getNomRangeBits(c) + sb.anGainExp)) * stepUDR);
      // Normalize to magnitude bits (output fractional point)
      invstep *= (1 << (shiftBits - src.getFixedPoint(c)));

      // Update convertFactor and stepSize fields
      cblk.convertFactor = invstep;
      cblk.stepSize = ((1L << (src.getNomRangeBits(c) + sb.anGainExp)) * stepUDR);

      if (intq) { // Quantizing int data
        // Since we used getNextCodeBlock() to get the int data then
        // 'offset' is 0 and 'scanw' is the width of the code-block
        // The input and output arrays are the same (i.e. "in place")
        for (j = w * h - 1; j >= 0; j--) {
          tmp = (int) (outarr[j] * invstep);
          outarr[j] = ((tmp < 0) ? (1 << 31) | (-tmp) : tmp);
        }
      } else { // Quantizing float data
        for (j = w * h - 1, k = infblk.offset + (h - 1) * infblk.scanw + w - 1, jmin = w * (h - 1);
            j >= 0;
            jmin -= w) {
          for (; j >= jmin; k--, j--) {
            tmp = (int) (infarr[k] * invstep);
            outarr[j] = ((tmp < 0) ? (1 << 31) | (-tmp) : tmp);
          }
          // Jump to beggining of previous line in input
          k -= infblk.scanw - w;
        }
      }
    }
    // Return the quantized code-block
    return cblk;
  }