tiffmapproducer.java

电子地图服务器,搭建自己的地图服务

/* Copyright (c) 2001 - 2007 TOPP - www.openplans.org.  All rights reserved.
 * This code is licensed under the GPL 2.0 license, availible at the root
 * application directory.
 */
package org.vfny.geoserver.wms.responses.map.tiff;

import java.awt.image.RenderedImage;
import java.io.IOException;
import java.io.OutputStream;
import java.util.logging.Level;
import java.util.logging.Logger;

import javax.imageio.ImageIO;
import javax.imageio.ImageWriter;
import javax.imageio.spi.ImageWriterSpi;
import javax.imageio.stream.ImageOutputStream;

import org.vfny.geoserver.global.WMS;
import org.vfny.geoserver.wms.GetMapProducer;
import org.vfny.geoserver.wms.WmsException;
import org.vfny.geoserver.wms.responses.DefaultRasterMapProducer;

import com.sun.media.imageioimpl.plugins.tiff.TIFFImageWriterSpi;

/**
 * Map producer for producing Tiff images out of a map.
 * 
 * @author Simone Giannecchini
 * @since 1.4.x
 * 
 */
public final class TiffMapProducer extends DefaultRasterMapProducer {
	/** A logger for this class. */
	private static final Logger LOGGER = org.geotools.util.logging.Logging.getLogger("org.vfny.geoserver.responses.wms.map");

	private final static ImageWriterSpi writerSPI = new TIFFImageWriterSpi();

	/**
	 * Creates a {@link GetMapProducer} to encode the {@link RenderedImage}
	 * generated in <code>outputFormat</code> format.
	 * 
	 * @param outputFormat
	 *            the output format.
	 */
	public TiffMapProducer(String outputFormat, String mime, WMS wms) {
		super(outputFormat, mime, wms);
	}

	/**
	 * Transforms the rendered image into the appropriate format, streaming to
	 * the output stream.
	 * 
	 * @param format
	 *            The name of the format
	 * @param image
	 *            The image to be formatted.
	 * @param outStream
	 *            The stream to write to.
	 * 
	 * @throws WmsException
	 *             not really.
	 * @throws IOException
	 *             if the image writing fails.
	 */
	public void formatImageOutputStream(RenderedImage image,
			OutputStream outStream) throws WmsException, IOException {
		// getting a writer
		if (LOGGER.isLoggable(Level.FINE)) {
			LOGGER.fine("Getting a writer for tiff");
		}

		// get a writer
		final ImageWriter writer = writerSPI.createWriterInstance();

		// getting a stream caching in memory
		final ImageOutputStream ioutstream = ImageIO
				.createImageOutputStream(outStream);

		// tiff
		if (LOGGER.isLoggable(Level.FINE)) {
			LOGGER.fine("Writing tiff image ...");
		}

		// do we want it to be 8 bits?
		if (this.format.equalsIgnoreCase("image/tiff8")
				|| (this.mapContext.getPaletteInverter() != null)) {
			image = forceIndexed8Bitmask(image);
		}

		// write it out
		writer.setOutput(ioutstream);
		writer.write(image);
		ioutstream.close();
		writer.dispose();

		if (LOGGER.isLoggable(Level.FINE)) {
			LOGGER.fine("Writing tiff image done!");
		}
	}

	public String getContentDisposition() {
		// can be null
		return null;
	}
}