imagefuser.java

基于arcims地理信息系统示例~！实现了大部分的地图操作

/*
COPYRIGHT 1992-2004 ESRI

TRADE SECRETS: ESRI PROPRIETARY AND CONFIDENTIAL
Unpublished material - all rights reserved under the 
Copyright Laws of the United States.

For additional information, contact:
Environmental Systems Research Institute, Inc.
Attn: Contracts Dept
380 New York Street
Redlands, California, USA 92373

email: [e-mail]
*/
package com.esri.aims.mtier.model.util;
/**
 * <p>ImageFuser</p>
 * <p>Description: Fuses multiple images toghether with transparencies. Intended for use with the</p>
 * <p>ArcIMS JavaConnector</p>
 * <p>Environmental Systems Research Institute</p>
 * <p>Example:
 * String[] images = new String[2];
 * images[0] = "C:/arcims/output/world.jpg";
 * images[1] = "C:/arcims/output/world_mountains.jpg";
 *
 * double[] transparencies = new double[2];
 * transparencies[0] = 1.0;
 * transparencies[1] = 0.5;
 *
 * ImageFuser imageFuser = new ImageFuser();
 * imageFuser.fuseImages(images, transparencies, "C:/arcims/output/world_fused.jpg", "PNG");
 * </p>
 */
import javax.media.jai.RenderedOp;


public class ImageFuser {

  /**
   * Constructs an instance of the ImageFuser class.
   */

  public ImageFuser() {
  }

  /**
   * Fuses a String array of images into one image. The output image is rendered based on the provided transparency values.
   * The first image in the list always has a transparency of 1. Subsequent images in the list need to have one transparency value
   * in the transparencies array for each image in the images array.
   * @param images String array containing either internet, or filesystem locations of images.
   * @param transparencies double array containing a transparency value for each image in the images array.
   * @param outputFile path and file of new file to be generated.
   * @param outputType type of image file to generate. JPG, TIFF, PNG.
   * @throws java.net.MalformedURLException If URL to image in images array is not functional.
   * @throws java.io.IOException
   * @throws java.io.FileNotFoundException if image file in images array is not found.
   * @throws Exception general exception information.
   */

  public static void fuseImages(String[] images, double[] transparencies, String outputFile, String outputType)
  throws java.net.MalformedURLException, java.io.IOException, java.io.FileNotFoundException, Exception{

    javax.media.jai.PlanarImage bottom = null;
    javax.media.jai.PlanarImage top = null;



    double aBottom = 1;
    String bottomImageExtension = null;
    String topImageExtension = null;

    for(int i=0; i<images.length; i++){




      if(i == 0){
        bottom = readSourceImage(images[i]);
        aBottom = 1.0;
        bottomImageExtension = images[i].substring(images[i].length() - 3, images[i].length());
      }
      else{
        top = readSourceImage(images[i]);
        topImageExtension = images[i].substring(images[i].length() - 3, images[i].length());
      }



      if(i > 0){
        javax.media.jai.PlanarImage afaBottom = calculateAlphaImage(bottom, aBottom, bottomImageExtension);
        javax.media.jai.PlanarImage afaTop = calculateAlphaImage(top,transparencies[i],topImageExtension);
        javax.media.jai.PlanarImage outImage = fuseImages(top, bottom, afaTop, afaBottom);

        if(i < images.length-1){
          bottom = outImage;
          aBottom = 1;
          bottomImageExtension = "";
        }
        else{
          saveImage(outImage,outputFile,outputType);
        }
      }
    }
  }

  //Calcuates the alpha value of a PlanarImage, based on the provided transparency. Returns a PlanarImage with the
  //calculated alpha values.

  private static javax.media.jai.PlanarImage calculateAlphaImage(javax.media.jai.PlanarImage src, double transparency, String imageExtension) throws Exception{
    javax.media.jai.PlanarImage afa = null;

    int alpha = (int)(transparency*255);
    Byte[] bandValues = new Byte[3];
    bandValues[0] = new Byte((byte)alpha);
    bandValues[1] = new Byte((byte)alpha);
    bandValues[2] = new Byte((byte)alpha);

    java.awt.image.renderable.ParameterBlock pb = new java.awt.image.renderable.ParameterBlock();
    pb.add((float)src.getWidth());
    pb.add((float)src.getHeight());
    pb.add(bandValues);
    return afa = javax.media.jai.JAI.create("constant",pb,null);
  }

  //Reads in image sources from both internet locations, and filesystems. Returns a PlanarImage of read image.

  private static javax.media.jai.PlanarImage readSourceImage(String fileName) throws java.net.MalformedURLException, java.io.IOException{
    javax.media.jai.PlanarImage src = null;

    if(fileName.startsWith("http://")){
      java.net.URL imageURL = new java.net.URL(fileName);
      java.net.URLConnection con = imageURL.openConnection();
      java.io.InputStream imageStream = com.sun.media.jai.codec.SeekableStream.wrapInputStream(con.getInputStream(), true);
      src = javax.media.jai.JAI.create("stream", imageStream);
    }
    else
      src = javax.media.jai.JAI.create("fileload", fileName);

    if(fileName.substring(fileName.length() - 3, fileName.length()).equalsIgnoreCase("png") && src.getNumBands() == 1){
      com.sun.media.jai.codec.SeekableStream is = null;
      if(fileName.startsWith("http://")){
        java.net.URL imageUrl = new java.net.URL(fileName);
        java.net.URLConnection con = imageUrl.openConnection();
        is = com.sun.media.jai.codec.SeekableStream.wrapInputStream(con.getInputStream(), true);
      }
      else
        is = new com.sun.media.jai.codec.FileSeekableStream(fileName);

      com.sun.media.jai.codec.PNGDecodeParam dec = new com.sun.media.jai.codec.PNGDecodeParam();
      dec.setExpandPalette(true);
      com.sun.media.jai.codec.ImageDecoder decoder = com.sun.media.jai.codec.ImageCodec.createImageDecoder("PNG",is,dec);
      java.awt.image.RenderedImage im = decoder.decodeAsRenderedImage();
      src = javax.media.jai.PlanarImage.wrapRenderedImage(im);
      }
      return src;
  }

  //Used internally to save the PlanarImage out to a file system.

  private static void saveImage(javax.media.jai.PlanarImage src, String fileName, String type) throws java.io.FileNotFoundException, java.io.IOException{
    if(type.equalsIgnoreCase("PNG8")){
      type = "PNG";
      java.awt.image.renderable.ParameterBlock pb = new java.awt.image.renderable.ParameterBlock();
      javax.media.jai.ColorCube colorMap = javax.media.jai.ColorCube.BYTE_496;
      javax.media.jai.KernelJAI[] ditherMask = javax.media.jai.KernelJAI.DITHER_MASK_443;
      pb.addSource(src).add(colorMap).add(ditherMask);
      src = javax.media.jai.JAI.create("ordereddither",pb);
    }
    else if(type.equalsIgnoreCase("JPG")){
      type = "JPEG";
    }
    else if(type.equalsIgnoreCase("TIF")){
      type = "TIFF";
    }
    else if(type.equalsIgnoreCase("TIFF") || type.equalsIgnoreCase("JPEG") || type.equalsIgnoreCase("PNG")){
      type = "JPEG";
    }
    javax.media.jai.JAI.create("filestore",src,fileName,type,null);
  }

  //Used internally to fuse the images together into one PlanarImage.

  private static javax.media.jai.PlanarImage fuseImages(javax.media.jai.PlanarImage srcTop, javax.media.jai.PlanarImage srcBottom, javax.media.jai.PlanarImage afaTop, javax.media.jai.PlanarImage afaBottom){
    java.awt.image.renderable.ParameterBlock pb = new java.awt.image.renderable.ParameterBlock();
    pb.addSource(srcTop);
    pb.addSource(srcBottom);
    pb.add(afaTop);
    pb.add(afaBottom);
    pb.add(new Boolean(false));
    pb.add(javax.media.jai.operator.CompositeDescriptor.NO_DESTINATION_ALPHA);
    return javax.media.jai.JAI.create("composite",pb,null);
  }
}