@DescribeResult(name = "result", description = "The contours feature collection")
  public SimpleFeatureCollection execute(
      @DescribeParameter(name = "data", description = "The raster to be used as the source")
          GridCoverage2D gc2d,
      @DescribeParameter(
              name = "band",
              description = "The source image band to process",
              min = 0,
              max = 1)
          Integer band,
      @DescribeParameter(name = "levels", description = "Values for which to generate contours")
          double[] levels,
      @DescribeParameter(
              name = "interval",
              description = "Interval between contour values (ignored if levels arg is supplied)",
              min = 0)
          Double interval,
      @DescribeParameter(
              name = "simplify",
              description = "Values for which to generate contours",
              min = 0)
          Boolean simplify,
      @DescribeParameter(
              name = "smooth",
              description = "Values for which to generate contours",
              min = 0)
          Boolean smooth,
      @DescribeParameter(
              name = "roi",
              description = "The geometry used to delineate the area of interest in model space",
              min = 0)
          Geometry roi,
      ProgressListener progressListener)
      throws ProcessException {

    //
    // initial checks
    //
    if (gc2d == null) {
      throw new ProcessException("Invalid input, source grid coverage should be not null");
    }
    if (band != null && (band < 0 || band >= gc2d.getNumSampleDimensions())) {
      throw new ProcessException("Invalid input, invalid band number:" + band);
    }
    boolean hasValues = !(levels == null || levels.length == 0);
    if (!hasValues && interval == null) {
      throw new ProcessException("One between interval and values must be valid");
    }

    // switch to geophisics if necessary
    gc2d = gc2d.view(ViewType.GEOPHYSICS);

    //
    // GRID TO WORLD preparation
    //
    final AffineTransform mt2D =
        (AffineTransform) gc2d.getGridGeometry().getGridToCRS2D(PixelOrientation.CENTER);

    // get the list of nodata, if any
    List<Object> noDataList = new ArrayList<Object>();
    for (GridSampleDimension sd : gc2d.getSampleDimensions()) {
      // grab all the explicit nodata
      final double[] sdNoData = sd.getNoDataValues();
      if (sdNoData != null) {
        for (double nodata : sdNoData) {
          noDataList.add(nodata);
        }
      }

      // handle also readers setting up nodata in a category with a specific name
      if (sd.getCategories() != null) {
        for (Category cat : sd.getCategories()) {
          if (cat.getName().equals(NO_DATA)) {
            final NumberRange<? extends Number> catRange = cat.getRange();
            if (catRange.getMinimum() == catRange.getMaximum()) {
              noDataList.add(catRange.getMinimum());
            } else {
              Range<Double> noData =
                  new Range<Double>(
                      catRange.getMinimum(),
                      catRange.isMinIncluded(),
                      catRange.getMaximum(),
                      catRange.isMaxIncluded());
              noDataList.add(noData);
            }
          }
        }
      }
    }

    // get the rendered image
    final RenderedImage raster = gc2d.getRenderedImage();

    // perform jai operation
    ParameterBlockJAI pb = new ParameterBlockJAI("Contour");
    pb.setSource("source0", raster);

    if (roi != null) {
      pb.setParameter("roi", CoverageUtilities.prepareROI(roi, mt2D));
    }
    if (band != null) {
      pb.setParameter("band", band);
    }
    if (interval != null) {
      pb.setParameter("interval", interval);
    } else {
      final ArrayList<Double> elements = new ArrayList<Double>(levels.length);
      for (double level : levels) elements.add(level);
      pb.setParameter("levels", elements);
    }
    if (simplify != null) {
      pb.setParameter("simplify", simplify);
    }
    if (smooth != null) {
      pb.setParameter("smooth", smooth);
    }
    if (noDataList != null) {
      pb.setParameter("nodata", noDataList);
    }

    final RenderedOp dest = JAI.create("Contour", pb);
    @SuppressWarnings("unchecked")
    final Collection<LineString> prop =
        (Collection<LineString>) dest.getProperty(ContourDescriptor.CONTOUR_PROPERTY_NAME);

    // wrap as a feature collection and return
    final SimpleFeatureType schema = CoverageUtilities.createFeatureType(gc2d, LineString.class);
    final SimpleFeatureBuilder builder = new SimpleFeatureBuilder(schema);
    int i = 0;
    final ListFeatureCollection featureCollection = new ListFeatureCollection(schema);
    final AffineTransformation jtsTransformation =
        new AffineTransformation(
            mt2D.getScaleX(),
            mt2D.getShearX(),
            mt2D.getTranslateX(),
            mt2D.getShearY(),
            mt2D.getScaleY(),
            mt2D.getTranslateY());
    for (LineString line : prop) {

      // get value
      Double value = (Double) line.getUserData();
      line.setUserData(null);
      // filter coordinates in place
      line.apply(jtsTransformation);

      // create feature and add to list
      builder.set("the_geom", line);
      builder.set("value", value);

      featureCollection.add(builder.buildFeature(String.valueOf(i++)));
    }

    // return value

    return featureCollection;
  }
  /**
   * Executes the raster to vector process.
   *
   * @param coverage the input grid coverage
   * @param band the coverage band to process; defaults to 0 if {@code null}
   * @param insideEdges whether boundaries between raster regions with data values (ie. not NODATA)
   *     should be returned; defaults to {@code true} if {@code null}
   * @param roi optional polygonal {@code Geometry} to define a sub-area within which vectorizing
   *     will be done
   * @param noDataValues optional list of values to treat as NODATA; regions with these values will
   *     not be represented in the returned features; if {@code null}, 0 is used as the single
   *     NODATA value; ignored if {@code classificationRanges} is provided
   * @param classificationRanges optional list of {@code Range} objects to pre-classify the input
   *     coverage prior to vectorizing; values not included in the list will be treated as NODATA;
   *     values in the first {@code Range} are classified to 1, those in the second {@code Range} to
   *     2 etc.
   * @param progressListener an optional listener
   * @return a feature collection where each feature has a {@code Polygon} ("the_geom") and an
   *     attribute "value" with value of the corresponding region in either {@code coverage} or the
   *     classified coverage (when {@code classificationRanges} is used)
   * @throws ProcessException
   */
  @DescribeResult(name = "result", description = "The polygon feature collection")
  public SimpleFeatureCollection execute(
      @DescribeParameter(name = "data", description = "The raster to be used as the source")
          GridCoverage2D coverage,
      @DescribeParameter(
              name = "band",
              description = "(Integer, default=0) the source image band to process",
              min = 0)
          Integer band,
      @DescribeParameter(
              name = "insideEdges",
              description =
                  "(Boolean, default=true) whether to vectorize boundaries between adjacent regions with non-outside values",
              min = 0)
          Boolean insideEdges,
      @DescribeParameter(
              name = "roi",
              description = "The geometry used to delineate the area of interest in model space",
              min = 0)
          Geometry roi,
      @DescribeParameter(
              name = "nodata",
              description = "Collection<Number>, default={0}) values to treat as NODATA",
              collectionType = Number.class,
              min = 0)
          Collection<Number> noDataValues,
      @DescribeParameter(
              name = "ranges",
              description =
                  "The list of ranges to be applied. \n"
                      + "Each range is expressed as 'OPEN START ; END CLOSE'\n"
                      + "where 'OPEN:=(|[, CLOSE=)|]',\n "
                      + "START is the low value, or nothing to imply -INF,\n"
                      + "CLOSE is the biggest value, or nothing to imply +INF",
              collectionType = Range.class,
              min = 0)
          List<Range> classificationRanges,
      ProgressListener progressListener)
      throws ProcessException {

    //
    // initial checks
    //
    if (coverage == null) {
      throw new ProcessException("Invalid input, source grid coverage should be not null");
    }

    if (band == null) {
      band = 0;
    } else if (band < 0 || band >= coverage.getNumSampleDimensions()) {
      throw new ProcessException("Invalid input, invalid band number:" + band);
    }

    // do we have classification ranges?
    boolean hasClassificationRanges =
        classificationRanges != null && classificationRanges.size() > 0;

    // apply the classification by setting 0 as the default value and using 1, ..., numClasses for
    // the other classes.
    // we use 0 also as the noData for the resulting coverage.
    if (hasClassificationRanges) {

      final RangeLookupProcess lookup = new RangeLookupProcess();
      coverage = lookup.execute(coverage, band, classificationRanges, progressListener);
    }

    // Use noDataValues to set the "outsideValues" parameter of the Vectorize
    // operation unless classificationRanges are in use, in which case the
    // noDataValues arg is ignored.
    List<Number> outsideValues = new ArrayList<Number>();
    if (noDataValues != null && !hasClassificationRanges) {
      outsideValues.addAll(noDataValues);
    } else {
      outsideValues.add(0);
    }

    //
    // GRID TO WORLD preparation
    //
    final AffineTransform mt2D =
        (AffineTransform) coverage.getGridGeometry().getGridToCRS2D(PixelOrientation.UPPER_LEFT);

    // get the rendered image
    final RenderedImage raster = coverage.getRenderedImage();

    // perform jai operation
    ParameterBlockJAI pb = new ParameterBlockJAI("Vectorize");
    pb.setSource("source0", raster);

    if (roi != null) {
      pb.setParameter("roi", CoverageUtilities.prepareROI(roi, mt2D));
    }
    pb.setParameter("band", band);
    pb.setParameter("outsideValues", outsideValues);
    if (insideEdges != null) {
      pb.setParameter("insideEdges", insideEdges);
    }
    // pb.setParameter("removeCollinear", false);

    final RenderedOp dest = JAI.create("Vectorize", pb);
    @SuppressWarnings("unchecked")
    final Collection<Polygon> prop =
        (Collection<Polygon>) dest.getProperty(VectorizeDescriptor.VECTOR_PROPERTY_NAME);

    // wrap as a feature collection and return
    final SimpleFeatureType featureType =
        CoverageUtilities.createFeatureType(coverage, Polygon.class);
    final SimpleFeatureBuilder builder = new SimpleFeatureBuilder(featureType);
    int i = 0;
    final ListFeatureCollection featureCollection = new ListFeatureCollection(featureType);
    final AffineTransformation jtsTransformation =
        new AffineTransformation(
            mt2D.getScaleX(),
            mt2D.getShearX(),
            mt2D.getTranslateX(),
            mt2D.getShearY(),
            mt2D.getScaleY(),
            mt2D.getTranslateY());
    for (Polygon polygon : prop) {
      // get value
      Double value = (Double) polygon.getUserData();
      polygon.setUserData(null);
      // filter coordinates in place
      polygon.apply(jtsTransformation);

      // create feature and add to list
      builder.set("the_geom", polygon);
      builder.set("value", value);

      featureCollection.add(builder.buildFeature(String.valueOf(i++)));
    }

    // return value
    return featureCollection;
  }
  public boolean extractTiffMetadata(File tifFile, TiffMeta surface)
      throws UnknownCRSException, FactoryException, TransformException, IOException {

    Preconditions.checkArgument(tifFile != null, "File is null.");

    GeoTiffReader gtr = new GeoTiffReader(tifFile);

    try {

      CoordinateReferenceSystem crs = gtr.getCoordinateReferenceSystem();
      surface.setCRS(crs);
      Integer epsgCode = CRS.lookupEpsgCode(crs, true);

      if (epsgCode == null) {
        ReferenceIdentifier name = crs.getName();
        String crsName = "Unknown";
        if (name != null) {
          crsName = name.toString();
        }
        throw new UnknownCRSException(crsName);
      }

      String srid = "EPSG:" + epsgCode;
      surface.setSrid(srid);

      //
      // extremaOp(surface, gtr.read(null));

      /*
       * Build the envelope and set to WGS84
       */
      GeneralEnvelope origEnv = gtr.getOriginalEnvelope();
      DirectPosition ll = origEnv.getLowerCorner();
      DirectPosition ur = origEnv.getUpperCorner();

      Envelope e = new Envelope();
      e.expandToInclude(ll.getOrdinate(0), ll.getOrdinate(1));
      e.expandToInclude(ur.getOrdinate(0), ur.getOrdinate(1));

      Geometry poly = envelopeToWgs84(epsgCode, e);

      if (poly instanceof Polygon) {
        surface.setEnvelope((Polygon) poly);
      }

      /*
       * Figure out the pixel size
       */
      ImageLayout imageLayout = gtr.getImageLayout();
      int imageWidth = imageLayout.getWidth(null);
      int imageHeight = imageLayout.getHeight(null);

      double pixelSizeX = e.getWidth() / imageWidth;
      double pixelSizeY = e.getHeight() / imageHeight;

      surface.setPixelSizeX(pixelSizeX);
      surface.setPixelSizeY(pixelSizeY);

      surface.setMinVal(0d);
      surface.setMaxVal(100d);

      GridCoverage2D gridCoverage2D = gtr.read(null);

      try {
        int nDims = gridCoverage2D.getNumSampleDimensions();
        surface.setNumSampleDimensions(nDims);

        extremaOp(surface, gridCoverage2D);

      } finally {
        gridCoverage2D.dispose(false);
      }

    } finally {

      gtr.dispose();
    }

    return true;
  }