static void decomp()

in java/TJBench.java [162:329]
148 lines of code
55 McCabe index (conditional complexity)

  static void decomp(byte[][] jpegBufs, int[] jpegSizes, Object dstBuf, int w,
                     int h, int subsamp, int jpegQual, String fileName,
                     int tilew, int tileh) throws Exception {
    String qualStr = new String(""), sizeStr, tempStr;
    TJDecompressor tjd;
    double elapsed, elapsedDecode;
    int ps = TJ.getPixelSize(pf), i, iter = 0;
    int scaledw, scaledh, pitch;
    YUVImage yuvImage = null;

    if (lossless)
      sf = TJ.UNSCALED;

    scaledw = sf.getScaled(w);
    scaledh = sf.getScaled(h);

    if (jpegQual > 0)
      qualStr = new String((lossless ? "_PSV" : "_Q") + jpegQual);

    tjd = new TJDecompressor();
    tjd.set(TJ.PARAM_STOPONWARNING, stopOnWarning ? 1 : 0);
    tjd.set(TJ.PARAM_BOTTOMUP, bottomUp ? 1 : 0);
    tjd.set(TJ.PARAM_FASTUPSAMPLE, fastUpsample ? 1 : 0);
    tjd.set(TJ.PARAM_FASTDCT, fastDCT ? 1 : 0);
    tjd.set(TJ.PARAM_SCANLIMIT, limitScans ? 500 : 0);
    tjd.set(TJ.PARAM_MAXMEMORY, maxMemory);
    tjd.set(TJ.PARAM_MAXPIXELS, maxPixels);

    if (isCropped(cr)) {
      try {
        tjd.setSourceImage(jpegBufs[0], jpegSizes[0]);
      } catch (TJException e) { handleTJException(e); }
    }
    tjd.setScalingFactor(sf);
    tjd.setCroppingRegion(cr);
    if (isCropped(cr)) {
      scaledw = cr.width != 0 ? cr.width : scaledw - cr.x;
      scaledh = cr.height != 0 ? cr.height : scaledh - cr.y;
    }
    pitch = scaledw * ps;

    if (dstBuf == null) {
      if ((long)pitch * (long)scaledh > (long)Integer.MAX_VALUE)
        throw new Exception("Image is too large");
      if (precision == 8)
        dstBuf = new byte[pitch * scaledh];
      else
        dstBuf = new short[pitch * scaledh];
    }

    /* Set the destination buffer to gray so we know whether the decompressor
       attempted to write to it */
    if (precision == 8)
      Arrays.fill((byte[])dstBuf, (byte)127);
    else if (precision == 12)
      Arrays.fill((short[])dstBuf, (short)2047);
    else
      Arrays.fill((short[])dstBuf, (short)32767);

    if (doYUV) {
      int width = doTile ? tilew : scaledw;
      int height = doTile ? tileh : scaledh;

      yuvImage = new YUVImage(width, yuvAlign, height, subsamp);
      Arrays.fill(yuvImage.getBuf(), (byte)127);
    }

    /* Benchmark */
    iter = -1;
    elapsed = elapsedDecode = 0.0;
    while (true) {
      int tile = 0;
      double start = getTime();

      for (int y = 0; y < h; y += tileh) {
        for (int x = 0; x < w; x += tilew, tile++) {
          int width = doTile ? Math.min(tilew, w - x) : scaledw;
          int height = doTile ? Math.min(tileh, h - y) : scaledh;

          try {
            tjd.setSourceImage(jpegBufs[tile], jpegSizes[tile]);
          } catch (TJException e) { handleTJException(e); }
          if (doYUV) {
            yuvImage.setBuf(yuvImage.getBuf(), width, yuvAlign, height,
                            subsamp);
            try {
              tjd.decompressToYUV(yuvImage);
            } catch (TJException e) { handleTJException(e); }
            double startDecode = getTime();
            tjd.setSourceImage(yuvImage);
            try {
              tjd.decompress8((byte[])dstBuf, x, y, pitch, pf);
            } catch (TJException e) { handleTJException(e); }
            if (iter >= 0)
              elapsedDecode += getTime() - startDecode;
          } else {
            try {
              if (precision == 8)
                tjd.decompress8((byte[])dstBuf, x, y, pitch, pf);
              else if (precision == 12)
                tjd.decompress12((short[])dstBuf, x, y, pitch, pf);
              else
                tjd.decompress16((short[])dstBuf, x, y, pitch, pf);
            } catch (TJException e) { handleTJException(e); }
          }
        }
      }
      elapsed += getTime() - start;
      if (iter >= 0) {
        iter++;
        if (elapsed >= benchTime)
          break;
      } else if (elapsed >= warmup) {
        iter = 0;
        elapsed = elapsedDecode = 0.0;
      }
    }
    if (doYUV)
      elapsed -= elapsedDecode;

    for (i = 0; i < jpegBufs.length; i++)
      jpegBufs[i] = null;
    jpegBufs = null;  jpegSizes = null;
    System.gc();

    if (quiet != 0) {
      System.out.format("%-6s%s",
                        sigFig((double)(w * h) / 1000000. *
                               (double)iter / elapsed, 4),
                        quiet == 2 ? "\n" : "  ");
      if (doYUV)
        System.out.format("%s\n",
                          sigFig((double)(w * h) / 1000000. *
                                 (double)iter / elapsedDecode, 4));
      else if (quiet != 2)
        System.out.print("\n");
    } else {
      System.out.format("%s --> Frame rate:         %f fps\n",
                        (doYUV ? "Decomp to YUV" : "Decompress   "),
                        (double)iter / elapsed);
      System.out.format("                  Throughput:         %f Megapixels/sec\n",
                        (double)(w * h) / 1000000. * (double)iter / elapsed);
      if (doYUV) {
        System.out.format("YUV Decode    --> Frame rate:         %f fps\n",
                          (double)iter / elapsedDecode);
        System.out.format("                  Throughput:         %f Megapixels/sec\n",
                          (double)(w * h) / 1000000. *
                          (double)iter / elapsedDecode);
      }
    }

    if (!write) return;

    if (sf.getNum() != 1 || sf.getDenom() != 1)
      sizeStr = new String(sf.getNum() + "_" + sf.getDenom());
    else if (tilew != w || tileh != h)
      sizeStr = new String(tilew + "x" + tileh);
    else
      sizeStr = new String("full");
    if (decompOnly)
      tempStr = new String(fileName + "_" + sizeStr + (bmp ? ".bmp" : ".ppm"));
    else
      tempStr = new String(fileName + "_" +
                           (lossless ? "LOSSLS" : SUBNAME[subsamp]) + qualStr +
                           "_" + sizeStr + (bmp ? ".bmp" : ".ppm"));

    tjd.saveImage(precision, tempStr, dstBuf, scaledw, 0, scaledh, pf);
  }