gov.nasa.worldwind.util.gdal
Class GDALUtils

java.lang.Object
  gov.nasa.worldwind.util.gdal.GDALUtils

public class GDALUtils
extends Object

Field Summary

static long	ALPHA_MASK
protected static byte	ALPHA_OPAQUE
protected static byte	ALPHA_TRANSPARENT
protected static CopyOnWriteArraySet<String>	failedLibraries
protected static String	GDAL_DATA_PATH
protected static String	GDAL_DRIVER_PATH
protected static String	gdalalljni
protected static AtomicBoolean	gdalIsAvailable
protected static String	JAVA_LIBRARY_PATH
protected static CopyOnWriteArraySet<String>	loadedLibraries
protected static String	OGR_DRIVER_PATH

Constructor Summary

GDALUtils()

Method Summary

protected static void	alterJavaLibraryPath(String newJavaLibraryPath)
protected static void	applyImageMask(byte[] alphaBand, IntBuffer maskBand)
protected static void	applyImageMask(int[] alphaBand, IntBuffer maskBand)
protected static void	applyImageMask(short[] alphaBand, IntBuffer maskBand)
protected static String	buildPathString(String[] folders, boolean addDefaultValues)
static double[]	calcGetGeoTransform(Sector sector, int width, int height) Calculates geo-transform matrix for a north-up raster
static boolean	canOpen(Object source) Checks if a data raster can is readable
static DataRaster	composeDataRaster(org.gdal.gdal.Dataset ds, AVList params)
protected static DataRaster	composeImageDataRaster(org.gdal.gdal.Dataset ds, AVList params) Opens image or elevation file, returns as a BufferedImage (even for elevations)
protected static DataRaster	composeNonImageDataRaster(org.gdal.gdal.Dataset ds, AVList params) The "composeDataRaster" method creates a ByteBufferRaster from an elevation (or non-image) Dataset.
protected static Double	convertStringToDouble(String s)
static org.gdal.osr.SpatialReference	createGeographicSRS()
protected static BufferedImage	detectVoidsAndMakeThemTransparent(BufferedImage sourceImage) Attempts to detect if there are any black|white|gray voids (also called black skirts) i n the image raster caused by inaccurate clipping.
static int[]	extractBandOrder(org.gdal.gdal.Dataset ds, AVList params)
protected static IntBuffer	extractImageMask(AVList params)
protected static void	extractMinMaxSampleValues(org.gdal.gdal.Dataset ds, org.gdal.gdal.Band band, AVList params)
static AVList	extractRasterParameters(org.gdal.gdal.Dataset ds)
static AVList	extractRasterParameters(org.gdal.gdal.Dataset ds, AVList params, boolean quickReadingMode) Extracts raster parameters to an AVList
protected static String	findGdalDataFolder()
protected static String[]	findGdalFolders()
protected static boolean	gdalPreLoadNativeLibrary(boolean allowLogErrors)
protected static String	getCurrentDirectory()
static String	getErrorMessage()
protected static LatLon	getLatLonForRasterPoint(double[] gt, int x, int y, org.gdal.osr.CoordinateTransformation ct)
protected static void	initialize()
protected static boolean	is32bitArchitecture()
protected static void	listAllRegisteredDrivers()
static org.gdal.gdal.Dataset	open(Object source) Opens image or elevation file, returns a DataSet object
static org.gdal.gdal.Dataset	open(Object source, boolean isSilentMode) Opens image or elevation file, returns a DataSet object
protected static void	replaceLibraryLoader()
protected static void	restoreJavaLibraryPath()
protected static void	scanFill(BufferedImage sourceImage)
protected static boolean	setNoDataValue(org.gdal.gdal.Band band, Double nodata)
protected static BufferedImage	verticalFlip(BufferedImage img) Flips image raster vertically

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

ALPHA_MASK

public static long ALPHA_MASK

ALPHA_OPAQUE

protected static byte ALPHA_OPAQUE

ALPHA_TRANSPARENT

protected static byte ALPHA_TRANSPARENT

failedLibraries

protected static final CopyOnWriteArraySet<String> failedLibraries

GDAL_DATA_PATH

protected static final String GDAL_DATA_PATH

See Also:

Constant Field Values

GDAL_DRIVER_PATH

protected static final String GDAL_DRIVER_PATH

See Also:

Constant Field Values

gdalalljni

protected static final String gdalalljni

gdalIsAvailable

protected static final AtomicBoolean gdalIsAvailable

JAVA_LIBRARY_PATH

protected static final String JAVA_LIBRARY_PATH

See Also:

Constant Field Values

loadedLibraries

protected static final CopyOnWriteArraySet<String> loadedLibraries

OGR_DRIVER_PATH

protected static final String OGR_DRIVER_PATH

See Also:

Constant Field Values

Constructor Detail

GDALUtils

public GDALUtils()

Method Detail

alterJavaLibraryPath

protected static void alterJavaLibraryPath(String newJavaLibraryPath)
                                    throws IllegalAccessException,
                                           NoSuchFieldException

Throws:

IllegalAccessException

NoSuchFieldException

applyImageMask

protected static void applyImageMask(byte[] alphaBand,
                                     IntBuffer maskBand)

applyImageMask

protected static void applyImageMask(int[] alphaBand,
                                     IntBuffer maskBand)

applyImageMask

protected static void applyImageMask(short[] alphaBand,
                                     IntBuffer maskBand)

buildPathString

protected static String buildPathString(String[] folders,
                                        boolean addDefaultValues)

calcGetGeoTransform

public static double[] calcGetGeoTransform(Sector sector,
                                           int width,
                                           int height)
                                    throws IllegalArgumentException

Calculates geo-transform matrix for a north-up raster

Parameters:

sector - Geographic area, a Sector

width - none-zero width of a raster

height - none-zero height of a raster

Returns:

an array of 6 doubles that contain a geo-transform matrix

Throws:

IllegalArgumentException - if sector is null, or raster size is zero

canOpen

public static boolean canOpen(Object source)

Checks if a data raster can is readable

Parameters:

source - the location of the local file, expressed as either a String path, a File, or a file URL.

Returns:

true, if source is readable

composeDataRaster

public static DataRaster composeDataRaster(org.gdal.gdal.Dataset ds,
                                           AVList params)
                                    throws IllegalArgumentException,
                                           WWRuntimeException

Throws:

IllegalArgumentException

WWRuntimeException

composeImageDataRaster

protected static DataRaster composeImageDataRaster(org.gdal.gdal.Dataset ds,
                                                   AVList params)
                                            throws IllegalArgumentException,
                                                   SecurityException,
                                                   WWRuntimeException

Opens image or elevation file, returns as a BufferedImage (even for elevations)

Parameters:

ds - GDAL's Dataset object

params - AVList of parameters

Returns:

DataRaster returns as a BufferedImage (even for elevations)

Throws:

IllegalArgumentException - if file is null

SecurityException - if file could not be read

WWRuntimeException - if GDAL library was not initialized

composeNonImageDataRaster

protected static DataRaster composeNonImageDataRaster(org.gdal.gdal.Dataset ds,
                                                      AVList params)
                                               throws IllegalArgumentException,
                                                      WWRuntimeException

The "composeDataRaster" method creates a ByteBufferRaster from an elevation (or non-image) Dataset.

Parameters:

ds - The GDAL dataset with data raster (expected only elevation raster); f or imagery rasters use composeImageDataRaster() method

params - , The AVList with properties (usually used to force projection info or sector)

Returns:

ByteBufferRaster as DataRaster

Throws:

IllegalArgumentException - if raster parameters (height, width, sector, etc) are invalid

WWRuntimeException - when invalid raster detected (like attempt to use the method for imagery raster)

convertStringToDouble

protected static Double convertStringToDouble(String s)

createGeographicSRS

public static org.gdal.osr.SpatialReference createGeographicSRS()
                                                         throws WWRuntimeException

Throws:

WWRuntimeException

detectVoidsAndMakeThemTransparent

protected static BufferedImage detectVoidsAndMakeThemTransparent(BufferedImage sourceImage)

Attempts to detect if there are any black|white|gray voids (also called black skirts) i n the image raster caused by inaccurate clipping. The algorithm checks each corner of the image and if it detects black|white|gray pixel, uses a scanline version of flood fill algorithm to make the area transparent. See more http://en.wikipedia.org/wiki/Flood_fill#Scanline_fill

Parameters:

sourceImage - a source image raster

Returns:

BufferedImage with voids (if detected) filled with a transparent pixel values

extractBandOrder

public static int[] extractBandOrder(org.gdal.gdal.Dataset ds,
                                     AVList params)
                              throws IllegalArgumentException,
                                     WWRuntimeException

Throws:

IllegalArgumentException

WWRuntimeException

extractImageMask

protected static IntBuffer extractImageMask(AVList params)

extractMinMaxSampleValues

protected static void extractMinMaxSampleValues(org.gdal.gdal.Dataset ds,
                                                org.gdal.gdal.Band band,
                                                AVList params)

extractRasterParameters

public static AVList extractRasterParameters(org.gdal.gdal.Dataset ds)
                                      throws IllegalArgumentException,
                                             WWRuntimeException

Throws:

IllegalArgumentException

WWRuntimeException

extractRasterParameters

public static AVList extractRasterParameters(org.gdal.gdal.Dataset ds,
                                             AVList params,
                                             boolean quickReadingMode)
                                      throws IllegalArgumentException,
                                             WWRuntimeException

Extracts raster parameters to an AVList

Parameters:

ds - A GDAL dataset

params - AVList to hold retrieved metadata, if null, a new instance will be created and returned as a return value

quickReadingMode - if quick reading mode is enabled GDAL will not spend much time on heavy calculations, like for example calculating Min/Max for entire elevation raster

Returns:

AVList with retrieved metadata

Throws:

IllegalArgumentException - when the passed dataset is null pr emtpy, or any of the dimension is 0

WWRuntimeException - if GDAL is not available, or a dataset contains no bands

The extractRasterParameters() sets next key/value pairs:

AVKey.WIDTH - the maximum width of the image

AVKey.HEIGHT - the maximum height of the image

AVKey.COORDINATE_SYSTEM - one of the next values: AVKey.COORDINATE_SYSTEM_SCREEN AVKey.COORDINATE_SYSTEM_GEOGRAPHIC AVKey.COORDINATE_SYSTEM_PROJECTED

AVKey.SECTOR - in case of Geographic CS, contains a regular Geographic Sector defined by lat/lon coordinates of corners in case of Projected CS, contains a bounding box of the area

AVKey.COORDINATE_SYSTEM_NAME

AVKey.PIXEL_WIDTH (Double) pixel size, UTM images usually specify 1 (1 meter); if missing and Geographic Coordinate System is specified will be calculated as LongitudeDelta/WIDTH

AVKey.PIXEL_HEIGHT (Double) pixel size, UTM images usually specify 1 (1 meter); if missing and Geographic Coordinate System is specified will be calculated as LatitudeDelta/HEIGHT

AVKey.ORIGIN (LatLon) specifies coordinate of the image's origin (one of the corners, or center) If missing, upper left corner will be set as origin

AVKey.DATE_TIME (0 terminated String, length == 20) if missing, current date & time will be used

AVKey.PIXEL_FORMAT required (valid values: AVKey.ELEVATION | AVKey.IMAGE } specifies weather it is a digital elevation model or image

AVKey.IMAGE_COLOR_FORMAT required if AVKey.PIXEL_FORMAT is AVKey.IMAGE (valid values: AVKey.COLOR and AVKey.MONOCHROME)

AVKey.DATA_TYPE required ( valid values: AVKey.INT16, and AVKey.FLOAT32 )

AVKey.VERSION optional, if missing a default will be used "NASA World Wind"

AVKey.DISPLAY_NAME, (String) optional, specifies a name of the document/image

AVKey.DESCRIPTION (String) optional, for any kind of descriptions

AVKey.MISSING_DATA_SIGNAL optional, set the AVKey.MISSING_DATA_SIGNAL ONLY if you know for sure that the specified value actually represents void (NODATA) areas. Elevation data usually has "-32767" (like DTED), or "-32768" like SRTM, but some has "0" (mostly images) and "-9999" like NED. Note! Setting "-9999" is very ambiguos because -9999 for elevation is valid value;

AVKey.MISSING_DATA_REPLACEMENT (String type forced by spec) Most images have "NODATA" as "0", elevations have as "-9999", or "-32768" (sometimes "-32767")

AVKey.COORDINATE_SYSTEM required, valid values AVKey.COORDINATE_SYSTEM_GEOGRAPHIC or AVKey.COORDINATE_SYSTEM_PROJECTED

AVKey.COORDINATE_SYSTEM_NAME Optional, A name of the Coordinates System as a String

AVKey.PROJECTION_EPSG_CODE Required; Integer; EPSG code or Projection Code If CS is Geodetic and EPSG code is not specified, a default WGS84 (4326) will be used

AVKey.PROJECTION_DATUM Optional, AVKey.PROJECTION_DESC Optional, AVKey.PROJECTION_NAME Optional, AVKey.PROJECTION_UNITS Optional,

AVKey.ELEVATION_UNIT Required, if AVKey.PIXEL_FORMAT = AVKey.ELEVATION, value: AVKey.UNIT_FOOT or AVKey.UNIT_METER (default, if not specified)

AVKey.RASTER_PIXEL, optional, values: AVKey.RASTER_PIXEL_IS_AREA or AVKey.RASTER_PIXEL_IS_POINT if not specified, default for images is RASTER_PIXEL_IS_AREA, and AVKey.RASTER_PIXEL_IS_POINT for elevations

findGdalDataFolder

protected static String findGdalDataFolder()

findGdalFolders

protected static String[] findGdalFolders()

gdalPreLoadNativeLibrary

protected static boolean gdalPreLoadNativeLibrary(boolean allowLogErrors)

getCurrentDirectory

protected static String getCurrentDirectory()

getErrorMessage

public static String getErrorMessage()

Returns:

returns an error string, if no errors returns null

getLatLonForRasterPoint

protected static LatLon getLatLonForRasterPoint(double[] gt,
                                                int x,
                                                int y,
                                                org.gdal.osr.CoordinateTransformation ct)

initialize

protected static void initialize()

is32bitArchitecture

protected static boolean is32bitArchitecture()

listAllRegisteredDrivers

protected static void listAllRegisteredDrivers()

open

public static org.gdal.gdal.Dataset open(Object source)
                                  throws FileNotFoundException,
                                         IllegalArgumentException,
                                         SecurityException,
                                         WWRuntimeException

Opens image or elevation file, returns a DataSet object

Parameters:

source - the location of the local file, expressed as either a String path, a File, or a file URL.

Returns:

returns a Dataset object

Throws:

FileNotFoundException - if file not found

IllegalArgumentException - if file is null

SecurityException - if file could not be read

WWRuntimeException - if GDAL library was not initialized

open

public static org.gdal.gdal.Dataset open(Object source,
                                         boolean isSilentMode)
                                  throws FileNotFoundException,
                                         IllegalArgumentException,
                                         SecurityException,
                                         WWRuntimeException

Opens image or elevation file, returns a DataSet object

Parameters:

source - the location of the local file, expressed as either a String path, a File, or a file URL.

isSilentMode - specifies a silent mode of reading file (usually needed for canRead() and readMetadata())

Returns:

returns a Dataset object

Throws:

FileNotFoundException - if file not found

IllegalArgumentException - if file is null

SecurityException - if file could not be read

WWRuntimeException - if GDAL library was not initialized

replaceLibraryLoader

protected static void replaceLibraryLoader()

restoreJavaLibraryPath

protected static void restoreJavaLibraryPath()

scanFill

protected static void scanFill(BufferedImage sourceImage)

setNoDataValue

protected static boolean setNoDataValue(org.gdal.gdal.Band band,
                                        Double nodata)

verticalFlip

protected static BufferedImage verticalFlip(BufferedImage img)

Flips image raster vertically

Parameters:

img - A source raster as a BufferedImage

Returns:

A vertically flipped image raster as a BufferedImage