WKBRasterWriter Class Reference

WKB Raster Writer, used in postGIS 2 but can be used elsewhere. More...

Public Member Functions
	WKBRasterWriter ()
void	reset ()
	Reset values before new write call. More...
byte[]	write (final GridCoverage coverage) throws IOException, FactoryException
	Encode given coverage in Postgis WKB. More...
void	write (final GridCoverage coverage, final OutputStream stream) throws IOException, FactoryException
	Encode given coverage in Postgis WKB. More...
void	write (final GridCoverage coverage, final OutputStream stream, final boolean littleEndian) throws IOException, FactoryException
	Encode given coverage in Postgis WKB. More...
byte[]	write (final RenderedImage image, final AffineTransform gridToCRS, final int srid) throws IOException
	Encode given image in Postgis WKB. More...
byte[]	write (final Raster image, final AffineTransform gridToCRS, final int srid) throws IOException
	Encode given image in Postgis WKB. More...
void	write (final RenderedImage image, AffineTransform gridToCRS, final int srid, final OutputStream stream) throws IOException
	Encode given image in Postgis WKB. More...
void	write (final Raster image, AffineTransform gridToCRS, final int srid, final OutputStream stream) throws IOException
	Encode given image in Postgis WKB. More...
void	write (final Raster image, AffineTransform gridToCRS, final int srid, OutputStream stream, final boolean littleEndian) throws IOException
	Encode given image in Postgis WKB. More...

Detailed Description

WKB Raster Writer, used in postGIS 2 but can be used elsewhere.

Author

Johann Sorel (Geomatys)

Constructor & Destructor Documentation

WKBRasterWriter()

WKBRasterWriter

(

)

                             {
    }

Member Function Documentation

reset()

void reset

(

)

Reset values before new write call.

                       {
    }

write() [1/8]

byte [] write

(

final GridCoverage

coverage

)

throws IOException, FactoryException

Encode given coverage in Postgis WKB.

Parameters

coverage

: grid coverage 2d , not null

Returns

byte[] encoded image

Exceptions

IOException

                                                                                          {
        final ByteArrayOutputStream out = new ByteArrayOutputStream();
        write(coverage, out);
        return out.toByteArray();
    }

Referenced by HexWKBRastDatatype.unparse(), WKBRastDatatype.unparse(), WKBRasterWriter.write(), and WKBRasterImageWriter.write().

write() [2/8]

void write	(	final GridCoverage	coverage,
		final OutputStream	stream
	)		throws IOException, FactoryException

Encode given coverage in Postgis WKB.

Parameters

coverage	: grid coverage 2d , not null
stream	: output stream to write in

Exceptions

IOException

                                                                                                                   {
        write(coverage, stream, true);
    }

References WKBRasterWriter.write().

write() [3/8]

void write	(	final GridCoverage	coverage,
		final OutputStream	stream,
		final boolean	littleEndian
	)		throws IOException, FactoryException

Encode given coverage in Postgis WKB.

Parameters

coverage	: grid coverage 2d , not null
stream	: output stream to write in
littleEndian	: wanted value encoding

Exceptions

IOException

                                                 {
        final GridGeometry gridGeometry = coverage.getGridGeometry();
        final CoordinateReferenceSystem crs = gridGeometry.getCoordinateReferenceSystem();
        final Integer srid = IdentifiedObjects.lookupEPSG(crs);
        if (srid == null) {
            throw new IOException("CoordinateReferenceSystem does not have an EPSG code.");
        }
        final MathTransform gridToCRS = coverage.getGridGeometry().getGridToCRS(PixelInCell.CELL_CENTER);
        if (!(gridToCRS instanceof AffineTransform)) {
            throw new IOException("Coverage GridToCRS transform is not affine.");
        }
        final RenderedImage image = coverage.render(null);
 
        write(image, (AffineTransform)gridToCRS, srid, stream);
    }

References WKBRasterWriter.write().

write() [4/8]

void write	(	final Raster	image,
		AffineTransform	gridToCRS,
		final int	srid,
		final OutputStream	stream
	)		throws IOException

Encode given image in Postgis WKB.

Parameters

image	: image , not null
gridToCRS	: image grid to crs, can be null
srid	: image srid
stream	: output stream to write in

Exceptions

IOException

                                                                          {
        write(image, gridToCRS, srid, stream, true);
    }

References WKBRasterWriter.write().

write() [5/8]

void write	(	final Raster	image,
		AffineTransform	gridToCRS,
		final int	srid,
		OutputStream	stream,
		final boolean	littleEndian
	)		throws IOException

Encode given image in Postgis WKB.

Parameters

image	: image , not null
gridToCRS	: image grid to crs, can be null
srid	: image srid
stream	: output stream to write in
littleEndian	: wanted value encoding

Exceptions

IOException

                                                                                                {
        if(gridToCRS == null){
            gridToCRS = new AffineTransform();
        }
 
        if (!(stream instanceof BufferedOutputStream)) {
            stream = new BufferedOutputStream(stream);
        }
 
        final DataOutput ds;
        if(littleEndian){
            ds = new LEDataOutputStream(stream);
        }else{
            ds = new DataOutputStream(stream);
        }
 
        final SampleModel sm = image.getSampleModel();
        final Raster raster = image;
        final int nbBand = sm.getNumBands();
        final int width = image.getWidth();
        final int height = image.getHeight();
        int databufferType = sm.getDataType();
        if(databufferType == DataBuffer.TYPE_INT){
            //special case, most image compression bands on single int when it would be byte
            if(sm.getSampleSize()[0] <= 8){
                databufferType = DataBuffer.TYPE_BYTE;
            }
        }
 
        final int pixelType = WKBRasterConstants.getPixelType(databufferType);
        final int bytePerpixel = WKBRasterConstants.getNbBytePerPixel(pixelType);
 
        //endianess
        ds.write( littleEndian ? 1 : 0 );
        //version, 0 for now
        ds.writeShort(0);
        //number of bands
        ds.writeShort(nbBand);
        //grid to crs
        ds.writeDouble(gridToCRS.getScaleX());
        ds.writeDouble(gridToCRS.getScaleY());
        ds.writeDouble(gridToCRS.getTranslateX());
        ds.writeDouble(gridToCRS.getTranslateY());
        ds.writeDouble(gridToCRS.getShearX());
        ds.writeDouble(gridToCRS.getShearY());
        //write srid
        ds.writeInt(srid);
        //width and height
        ds.writeShort(width);
        ds.writeShort(height);
 
        //write each band
        for(int b=0;b<nbBand;b++){
 
            // band description
            final byte flags = (byte) pixelType;
            // OffDatabase = false
            // TODO HasNodata : we don't have informations for no data
            //      this would requiere a SampleDimension object
            // IsNodata = false
            // Reserved = false
            ds.write(flags);
 
            // TODO no data value
            ds.write(new byte[bytePerpixel]);
 
            //write values
            for(int y=raster.getMinY(),maxy=raster.getMinY()+height;y<maxy;y++){
                for(int x=raster.getMinX(),maxx=raster.getMinX()+width;x<maxx;x++){
                    switch(databufferType){
                        case DataBuffer.TYPE_BYTE :     ds.writeByte( (byte)raster.getSample(x, y, b)); break;
                        case DataBuffer.TYPE_SHORT :    ds.writeShort( (short)raster.getSample(x, y, b)); break;
                        case DataBuffer.TYPE_USHORT :   ds.writeShort( (short)raster.getSample(x, y, b)); break;
                        case DataBuffer.TYPE_INT :      ds.writeInt( raster.getSample(x, y, b)); break;
                        case DataBuffer.TYPE_FLOAT :    ds.writeFloat( raster.getSampleFloat(x, y, b)); break;
                        case DataBuffer.TYPE_DOUBLE :   ds.writeDouble( raster.getSampleDouble(x, y, b)); break;
                    }
                }
            }
 
        }
        stream.flush();
    }

References WKBRasterConstants.getNbBytePerPixel(), and WKBRasterConstants.getPixelType().

write() [6/8]

byte [] write	(	final Raster	image,
		final AffineTransform	gridToCRS,
		final int	srid
	)		throws IOException

Encode given image in Postgis WKB.

Parameters

image	: image , not null
gridToCRS	: image grid to crs, can be null
srid	: image srid

Returns

byte[] encoded image

Exceptions

IOException

                                               {
        final ByteArrayOutputStream out = new ByteArrayOutputStream();
        write(image, gridToCRS, srid, out);
        return out.toByteArray();
    }

References WKBRasterWriter.write().

write() [7/8]

void write	(	final RenderedImage	image,
		AffineTransform	gridToCRS,
		final int	srid,
		final OutputStream	stream
	)		throws IOException

Encode given image in Postgis WKB.

Parameters

image	: image , not null
gridToCRS	: image grid to crs, can be null
srid	: image srid
stream	: output stream to write in

Exceptions

IOException

                                                                          {
        write(image.getData(), gridToCRS, srid, stream, true);
    }

References WKBRasterWriter.write().

write() [8/8]

byte [] write	(	final RenderedImage	image,
		final AffineTransform	gridToCRS,
		final int	srid
	)		throws IOException

Encode given image in Postgis WKB.

Parameters

image	: image , not null
gridToCRS	: image grid to crs, can be null
srid	: image srid

Returns

byte[] encoded image

Exceptions

IOException

                                               {
        final ByteArrayOutputStream out = new ByteArrayOutputStream();
        write(image, gridToCRS, srid, out);
        return out.toByteArray();
    }

References WKBRasterWriter.write().