This is an automated email from the ASF dual-hosted git repository.
desruisseaux pushed a commit to branch geoapi-4.0
in repository https://gitbox.apache.org/repos/asf/sis.git
commit 869a6d4541d78390e8083f65d82eba8b68666185
Author: Martin Desruisseaux <martin.desruisse...@geomatys.com>
AuthorDate: Tue Nov 30 14:13:41 2021 +0100
Allow to specify default color palettes for netCDF variables.
This is an internal API for now, with colors depending on conventions.
---
.../apache/sis/coverage/grid/ImageRenderer.java | 69 +++++++++++++++++++++-
.../sis/internal/coverage/j2d/Colorizer.java | 3 +-
.../apache/sis/internal/earth/netcdf/GCOM_C.java | 31 ++++++++++
.../org/apache/sis/internal/netcdf/Convention.java | 26 +++++++-
.../org/apache/sis/internal/netcdf/Raster.java | 28 ++++++++-
.../apache/sis/internal/netcdf/RasterResource.java | 31 +++++++---
6 files changed, 173 insertions(+), 15 deletions(-)
diff --git
a/core/sis-feature/src/main/java/org/apache/sis/coverage/grid/ImageRenderer.java
b/core/sis-feature/src/main/java/org/apache/sis/coverage/grid/ImageRenderer.java
index e269dc3..bf2f424 100644
---
a/core/sis-feature/src/main/java/org/apache/sis/coverage/grid/ImageRenderer.java
+++
b/core/sis-feature/src/main/java/org/apache/sis/coverage/grid/ImageRenderer.java
@@ -16,9 +16,11 @@
*/
package org.apache.sis.coverage.grid;
-import java.util.Hashtable;
import java.util.Arrays;
+import java.util.Hashtable;
+import java.util.function.Function;
import java.nio.Buffer;
+import java.awt.Color;
import java.awt.Point;
import java.awt.Rectangle;
import java.awt.image.ColorModel;
@@ -37,6 +39,7 @@ import org.apache.sis.image.DataType;
import org.apache.sis.coverage.SubspaceNotSpecifiedException;
import org.apache.sis.coverage.MismatchedCoverageRangeException;
import org.apache.sis.coverage.SampleDimension;
+import org.apache.sis.coverage.Category;
import org.apache.sis.internal.coverage.j2d.Colorizer;
import org.apache.sis.internal.coverage.j2d.DeferredProperty;
import org.apache.sis.internal.coverage.j2d.RasterFactory;
@@ -247,7 +250,10 @@ public class ImageRenderer {
private int[] bankIndices;
/**
- * The band to be made visible (usually 0). All other bands, if any will
be ignored.
+ * The band to use for defining pixel colors when the image is displayed
on screen.
+ * All other bands, if any, will exist in the raster but be ignored at
display time.
+ *
+ * @see #setVisibleBand(int)
*/
private int visibleBand;
@@ -258,6 +264,15 @@ public class ImageRenderer {
private DataBuffer buffer;
/**
+ * The colors to use for each category. Never {@code null}.
+ * The function may return {@code null}, which means transparent.
+ * The default value is {@link Colorizer#GRAYSCALE}.
+ *
+ * @see #setCategoryColors(Function)
+ */
+ private Function<Category,Color[]> colors;
+
+ /**
* The properties to give to the image, or {@code null} if none.
*
* @see #addProperty(String, Object)
@@ -347,6 +362,7 @@ public class ImageRenderer {
this.pixelStride = toIntExact(pixelStride);
this.scanlineStride = toIntExact(scanlineStride);
this.offsetZ = offsetZ;
+ this.colors = Colorizer.GRAYSCALE;
}
/**
@@ -603,6 +619,53 @@ public class ImageRenderer {
}
/**
+ * Specifies the band to use for defining pixel colors when the image is
displayed on screen.
+ * All other bands, if any, will exist in the raster but be ignored at
display time.
+ * The default value is 0, the first (and often only) band.
+ *
+ * <div class="note"><b>Implementation note:</b>
+ * an {@link java.awt.image.IndexColorModel} will be used for displaying
the image.</div>
+ *
+ * @param band the band to use for display purpose.
+ * @throws IllegalArgumentException if the given band is not between 0
(inclusive)
+ * and {@link #getNumBands()} (exclusive).
+ *
+ * @since 1.2
+ */
+ public void setVisibleBand(final int band) {
+ ArgumentChecks.ensureBetween("band", 0, getNumBands() - 1, band);
+ visibleBand = band;
+ }
+
+ /**
+ * Specifies the colors to apply for each category in a sample dimension.
+ * The given function can return {@code null}, which means transparent.
+ * If this method is never invoked, then the default is a grayscale for
+ * {@linkplain Category#isQuantitative() quantitative categories} and
+ * transparent for qualitative categories (typically "no data" values).
+ *
+ * <h4>Example</h4>
+ * the following code specifies a color palette from blue to red with
white in the middle.
+ * This is useful for data with a clear 0 (white) in the middle of the
range,
+ * with a minimal value equals to the negative of the maximal value.
+ *
+ * {@preformat java
+ * setCategoryColors((category) -> category.isQuantitative() ? new
Color[] {
+ * Color.BLUE, Color.CYAN, Color.WHITE, Color.YELLOW, Color.RED
+ * } : null);
+ * }
+ *
+ * @param colors the colors to use for each category. The {@code colors}
argument can not be null,
+ * but {@code colors.apply(Category)} can return null.
+ *
+ * @since 1.2
+ */
+ public void setCategoryColors(final Function<Category,Color[]> colors) {
+ ArgumentChecks.ensureNonNull("colors", colors);
+ this.colors = colors;
+ }
+
+ /**
* Creates a raster with the data specified by the last call to a {@code
setData(…)} method.
* The raster upper-left corner is located at the position given by {@link
#getBounds()}.
* The returned raster is often an instance of {@link WritableRaster}, but
read-only rasters are also allowed.
@@ -666,7 +729,7 @@ public class ImageRenderer {
@SuppressWarnings("UseOfObsoleteCollectionType")
public RenderedImage createImage() {
final Raster raster = createRaster();
- final Colorizer colorizer = new Colorizer(Colorizer.GRAYSCALE);
+ final Colorizer colorizer = new Colorizer(colors);
final ColorModel colors;
if (colorizer.initialize(bands[visibleBand]) ||
colorizer.initialize(raster.getSampleModel(), visibleBand)) {
colors = colorizer.createColorModel(buffer.getDataType(),
bands.length, visibleBand);
diff --git
a/core/sis-feature/src/main/java/org/apache/sis/internal/coverage/j2d/Colorizer.java
b/core/sis-feature/src/main/java/org/apache/sis/internal/coverage/j2d/Colorizer.java
index 1b3a83f..26e1c45 100644
---
a/core/sis-feature/src/main/java/org/apache/sis/internal/coverage/j2d/Colorizer.java
+++
b/core/sis-feature/src/main/java/org/apache/sis/internal/coverage/j2d/Colorizer.java
@@ -98,7 +98,8 @@ public final class Colorizer {
/**
* Blue to red color palette with white in the middle. Useful for data
with a clear 0 (white)
- * in the range center and negative and positive values (to appear blue
and red respectively).
+ * in the middle of the range and with minimal value equals to the
negative of maximal value
+ * (to appear blue and red respectively).
* Used for debugging purposes; production code should use a {@code
PaletteFactory} instead.
*/
@Debug
diff --git
a/profiles/sis-japan-profile/src/main/java/org/apache/sis/internal/earth/netcdf/GCOM_C.java
b/profiles/sis-japan-profile/src/main/java/org/apache/sis/internal/earth/netcdf/GCOM_C.java
index 9df14da..3e23d77 100644
---
a/profiles/sis-japan-profile/src/main/java/org/apache/sis/internal/earth/netcdf/GCOM_C.java
+++
b/profiles/sis-japan-profile/src/main/java/org/apache/sis/internal/earth/netcdf/GCOM_C.java
@@ -16,12 +16,15 @@
*/
package org.apache.sis.internal.earth.netcdf;
+import java.util.Objects;
import java.util.Set;
import java.util.Map;
import java.util.HashMap;
import java.util.Collections;
import java.util.LinkedHashSet;
import java.util.regex.Pattern;
+import java.util.function.Function;
+import java.awt.Color;
import javax.measure.Unit;
import javax.measure.format.ParserException;
import org.opengis.referencing.crs.ProjectedCRS;
@@ -41,6 +44,7 @@ import
org.apache.sis.referencing.operation.transform.TransferFunction;
import org.apache.sis.referencing.operation.transform.MathTransforms;
import org.apache.sis.referencing.operation.matrix.Matrix3;
import org.apache.sis.referencing.CommonCRS;
+import org.apache.sis.coverage.Category;
import org.apache.sis.measure.NumberRange;
import org.apache.sis.measure.Units;
import ucar.nc2.constants.CF;
@@ -536,4 +540,31 @@ public final class GCOM_C extends Convention {
}
return super.getUnitFallback(data);
}
+
+ /**
+ * Returns the colors to use for each category, or {@code null} for the
default colors.
+ *
+ * @param data the variable for which to get the colors.
+ * @return colors to use for each category, or {@code null} for the
default.
+ */
+ @Override
+ public Function<Category,Color[]> getColors(final Variable data) {
+ if (QA_FLAG.equals(data.getName())) {
+ return (category) -> {
+ final NumberRange<?> range = category.getSampleRange();
+ if (Objects.equals(range.getMinValue(), range.getMaxValue())) {
+ return null; // A "no data" value.
+ }
+ /*
+ * Following colors are not really appropriate for "QA_flag"
because that variable is a bitmask
+ * rather than a continuous coverage. Following code may be
replaced by a better color palette
+ * in a future version.
+ */
+ return new Color[] {
+ Color.BLUE, Color.CYAN, Color.YELLOW, Color.RED
+ };
+ };
+ }
+ return super.getColors(data);
+ }
}
diff --git
a/storage/sis-netcdf/src/main/java/org/apache/sis/internal/netcdf/Convention.java
b/storage/sis-netcdf/src/main/java/org/apache/sis/internal/netcdf/Convention.java
index 19f26c8..d73cf32 100644
---
a/storage/sis-netcdf/src/main/java/org/apache/sis/internal/netcdf/Convention.java
+++
b/storage/sis-netcdf/src/main/java/org/apache/sis/internal/netcdf/Convention.java
@@ -23,6 +23,8 @@ import java.util.Iterator;
import java.util.Collections;
import java.util.LinkedHashMap;
import java.util.Locale;
+import java.util.function.Function;
+import java.awt.Color;
import javax.measure.Unit;
import javax.measure.format.ParserException;
import org.opengis.referencing.crs.ProjectedCRS;
@@ -35,6 +37,7 @@ import org.apache.sis.referencing.CommonCRS;
import org.apache.sis.internal.referencing.LazySet;
import org.apache.sis.measure.MeasurementRange;
import org.apache.sis.measure.NumberRange;
+import org.apache.sis.coverage.Category;
import org.apache.sis.math.Vector;
import org.apache.sis.util.Numbers;
import org.apache.sis.util.resources.Errors;
@@ -64,7 +67,7 @@ import ucar.nc2.constants.CF;
* @author Johann Sorel (Geomatys)
* @author Martin Desruisseaux (Geomatys)
* @author Alexis Manin (Geomatys)
- * @version 1.1
+ * @version 1.2
*
* @see <a href="https://issues.apache.org/jira/browse/SIS-315";>SIS-315</a>
*
@@ -766,4 +769,25 @@ public class Convention {
public Unit<?> getUnitFallback(final Variable data) throws ParserException
{
return null;
}
+
+ /**
+ * Returns the band to use for defining pixel colors when the image is
displayed on screen.
+ * All other bands, if any, will exist in the raster but be ignored at
display time.
+ * The default value is 0, the first (and often only) band.
+ *
+ * @return the band on which {@link #getColors(Variable)} will apply.
+ */
+ public int getVisibleBand() {
+ return 0;
+ }
+
+ /**
+ * Returns the colors to use for each category, or {@code null} for the
default colors.
+ *
+ * @param data the variable for which to get the colors.
+ * @return colors to use for each category, or {@code null} for the
default.
+ */
+ public Function<Category,Color[]> getColors(final Variable data) {
+ return null;
+ }
}
diff --git
a/storage/sis-netcdf/src/main/java/org/apache/sis/internal/netcdf/Raster.java
b/storage/sis-netcdf/src/main/java/org/apache/sis/internal/netcdf/Raster.java
index c17ea2e..44196cd 100644
---
a/storage/sis-netcdf/src/main/java/org/apache/sis/internal/netcdf/Raster.java
+++
b/storage/sis-netcdf/src/main/java/org/apache/sis/internal/netcdf/Raster.java
@@ -17,10 +17,13 @@
package org.apache.sis.internal.netcdf;
import java.util.List;
+import java.util.function.Function;
+import java.awt.Color;
import java.awt.image.DataBuffer;
import java.awt.image.RenderedImage;
import java.awt.image.RasterFormatException;
import org.opengis.coverage.CannotEvaluateException;
+import org.apache.sis.coverage.Category;
import org.apache.sis.coverage.SampleDimension;
import org.apache.sis.coverage.grid.GridGeometry;
import org.apache.sis.coverage.grid.GridExtent;
@@ -40,7 +43,7 @@ import org.apache.sis.coverage.grid.BufferedGridCoverage;
* but it is {@link ImageRenderer} responsibility to perform this substitution
as an optimization.</p>
*
* @author Martin Desruisseaux (IRD, Geomatys)
- * @version 1.1
+ * @version 1.2
* @since 1.0
* @module
*/
@@ -57,20 +60,37 @@ final class Raster extends BufferedGridCoverage {
private final int[] bandOffsets;
/**
+ * The band to use for defining pixel colors when the image is displayed
on screen.
+ * All other bands, if any, will exist in the raster but be ignored at
display time.
+ *
+ * @see Convention#getVisibleBand()
+ */
+ private final int visibleBand;
+
+ /**
* Name to display in error messages. Not to be used for processing.
*/
private final String label;
/**
+ * The colors to use for each category, or {@code null} for default.
+ * The function may return {@code null}, which means transparent.
+ */
+ private final Function<Category,Color[]> colors;
+
+ /**
* Creates a new raster from the given resource.
*/
Raster(final GridGeometry domain, final List<SampleDimension> range, final
DataBuffer data,
- final int pixelStride, final int[] bandOffsets, final String label)
+ final String label, final int pixelStride, final int[] bandOffsets,
final int visibleBand,
+ final Function<Category,Color[]> colors)
{
super(domain, range, data);
this.label = label;
+ this.colors = colors;
this.pixelStride = pixelStride;
this.bandOffsets = bandOffsets;
+ this.visibleBand = visibleBand;
}
/**
@@ -85,6 +105,10 @@ final class Raster extends BufferedGridCoverage {
if (bandOffsets != null) {
renderer.setInterleavedPixelOffsets(pixelStride, bandOffsets);
}
+ if (colors != null) {
+ renderer.setCategoryColors(colors);
+ }
+ renderer.setVisibleBand(visibleBand);
return renderer.createImage();
} catch (IllegalArgumentException | ArithmeticException |
RasterFormatException e) {
throw new
CannotEvaluateException(Resources.format(Resources.Keys.CanNotRender_2, label,
e), e);
diff --git
a/storage/sis-netcdf/src/main/java/org/apache/sis/internal/netcdf/RasterResource.java
b/storage/sis-netcdf/src/main/java/org/apache/sis/internal/netcdf/RasterResource.java
index 7001f2e..4fa11f7 100644
---
a/storage/sis-netcdf/src/main/java/org/apache/sis/internal/netcdf/RasterResource.java
+++
b/storage/sis-netcdf/src/main/java/org/apache/sis/internal/netcdf/RasterResource.java
@@ -152,6 +152,14 @@ public final class RasterResource extends
AbstractGridResource implements Resour
private final int bandDimension;
/**
+ * The band to use for defining pixel colors when the image is displayed
on screen.
+ * All other bands, if any, will exist in the raster but be ignored at
display time.
+ *
+ * @see Convention#getVisibleBand()
+ */
+ private final int visibleBand;
+
+ /**
* Path to the netCDF file for information purpose, or {@code null} if
unknown.
*
* @see #getComponentFiles()
@@ -182,13 +190,14 @@ public final class RasterResource extends
AbstractGridResource implements Resour
final int numBands, final int bandDim, final Object lock)
{
super(decoder.listeners);
- data = bands.toArray(new Variable[bands.size()]);
- ranges = new SampleDimension[numBands];
- identifier = decoder.nameFactory.createLocalName(decoder.namespace,
name);
- location = decoder.location;
+ this.lock = lock;
gridGeometry = grid;
bandDimension = bandDim;
- this.lock = lock;
+ location = decoder.location;
+ identifier = decoder.nameFactory.createLocalName(decoder.namespace,
name);
+ visibleBand = decoder.convention().getVisibleBand();
+ ranges = new SampleDimension[numBands];
+ data = bands.toArray(new Variable[bands.size()]);
assert data.length == (bandDimension >= 0 ? 1 : ranges.length);
}
@@ -523,7 +532,7 @@ public final class RasterResource extends
AbstractGridResource implements Resour
* Adds the "missing value" or "fill value" as qualitative categories.
If a value has both roles, use "missing value"
* as category name. If the sample values are already real values,
then the "no data" values have been replaced by NaN
* values by Variable.replaceNaN(Object). The qualitative categories
constructed below must be consistent with the NaN
- * values created by 'replaceNaN'.
+ * values created by `replaceNaN`.
*/
boolean setBackground = true;
int ordinal = band.hasRealValues() ? 0 : -1;
@@ -659,7 +668,7 @@ public final class RasterResource extends
AbstractGridResource implements Resour
}
/*
* Iterate over netCDF variables in the order they appear in the
file, not in the order requested
- * by the 'range' argument. The intent is to perform sequential
I/O as much as possible, without
+ * by the `range` argument. The intent is to perform sequential
I/O as much as possible, without
* seeking backward. In the (uncommon) case where bands are one of
the variable dimension instead
* than different variables, the reading of the whole variable
occurs during the first iteration.
*/
@@ -721,11 +730,17 @@ public final class RasterResource extends
AbstractGridResource implements Resour
throw new DataStoreContentException(canNotReadFile(), e);
}
}
+ /*
+ * At this point the I/O operation is completed and sample values have
been stored in a NIO buffer.
+ * Provide to `Raster` all information needed for building a
`RenderedImage` when requested.
+ */
if (imageBuffer == null) {
throw new
DataStoreContentException(Errors.getResources(getLocale()).getString(Errors.Keys.UnsupportedType_1,
dataType.name()));
}
+ final Variable main = data[visibleBand];
final Raster raster = new Raster(domain,
UnmodifiableArrayList.wrap(bands), imageBuffer,
- rangeIndices.getPixelStride(), bandOffsets,
String.valueOf(identifier));
+ String.valueOf(identifier), rangeIndices.getPixelStride(),
bandOffsets, visibleBand,
+ main.decoder.convention().getColors(main));
logReadOperation(location, domain, startTime);
return raster;
}
