imagereader.java

gcc的组建

                      {
                        dest = t.createBufferedImage (width, height);
                        break;
                      }
                    if (destType == null)
                      throw new IIOException ("invalid destination type");

                  }
              }
          }
      }
    if (dest == null)
      {
        Rectangle srcRegion = new Rectangle ();
        Rectangle destRegion = new Rectangle ();

        computeRegions (param, width, height, null, srcRegion, destRegion);

        if (destRegion.isEmpty())
          throw new IllegalArgumentException ("destination region empty");

        if (destType == null)
          {
            Object o = imageTypes.next();
            if (! (o instanceof ImageTypeSpecifier))
              throw new IllegalArgumentException ("non-ImageTypeSpecifier"
                                                  + " object");

            dest = ((ImageTypeSpecifier) o).createBufferedImage
              (destRegion.width, destRegion.height);
          }
        else
          dest = destType.createBufferedImage
            (destRegion.width, destRegion.height);
      }
    return dest;
  }

  /**
   * Get the metadata associated with this image.  If the reader is
   * set to ignore metadata or does not support reading metadata, or
   * if no metadata is available then null is returned.
   *
   * This more specific version of getImageMetadata(int) can be used
   * to restrict metadata retrieval to specific formats and node
   * names, which can limit the amount of data that needs to be
   * processed.
   *
   * @param imageIndex the frame index
   * @param formatName the format of metadata requested
   * @param nodeNames a set of Strings specifiying node names to be
   * retrieved
   *
   * @return a metadata object, or null
   *
   * @exception IllegalStateException if input has not been set
   * @exception IndexOutOfBoundsException if the frame index is
   * out-of-bounds
   * @exception IllegalArgumentException if formatName is null
   * @exception IllegalArgumentException if nodeNames is null
   * @exception IOException if a read error occurs
   */
  public IIOMetadata getImageMetadata (int imageIndex,
                                       String formatName,
                                       Set nodeNames)
    throws IOException
  {
    if (formatName == null || nodeNames == null)
      throw new IllegalArgumentException ("null argument");

    return getImageMetadata (imageIndex);
  }

  /**
   * Get the index at which the next image will be read.  If
   * seekForwardOnly is true then the returned value will increase
   * monotonically each time an image frame is read.  If
   * seekForwardOnly is false then the returned value will always be
   * 0.
   *
   * @return the current frame index
   */
  public int getMinIndex()
  {
    return minIndex;
  }

  /**
   * Get the image type specifier that most closely represents the
   * internal data representation used by this reader.  This value
   * should be included in the return value of getImageTypes.
   *
   * @param imageIndex the frame index
   *
   * @return an image type specifier
   *
   * @exception IllegalStateException if input has not been set
   * @exception IndexOutOfBoundsException if the frame index is
   * out-of-bounds
   * @exception IOException if a read error occurs
   */
  public ImageTypeSpecifier getRawImageType (int imageIndex)
    throws IOException
  {
    return (ImageTypeSpecifier) getImageTypes(imageIndex).next();
  }

  /**
   * Calculate a source region based on the given source image
   * dimensions and parameters.  Subsampling offsets and a source
   * region are taken from the given image read parameters and used to
   * clip the given image dimensions, returning a new rectangular
   * region as a result.
   *
   * @param param image parameters, or null
   * @param srcWidth the width of the source image
   * @param srcHeight the height of the source image
   *
   * @return a clipped rectangle
   */
  protected static Rectangle getSourceRegion (ImageReadParam param,
					      int srcWidth,
					      int srcHeight)
  {
    Rectangle clippedRegion = new Rectangle (0, 0, srcWidth, srcHeight);

    if (param != null)
      {
        Rectangle srcRegion = param.getSourceRegion();

        if (srcRegion != null)
          {
            clippedRegion.x = srcRegion.x > clippedRegion.x
              ? srcRegion.x : clippedRegion.x;
            clippedRegion.y = srcRegion.y > clippedRegion.y
              ? srcRegion.y : clippedRegion.y;
            clippedRegion.width = srcRegion.width > clippedRegion.width
              ? srcRegion.width : clippedRegion.width;
            clippedRegion.height = srcRegion.height > clippedRegion.height
              ? srcRegion.height : clippedRegion.height;
          }

        int xOffset = param.getSubsamplingXOffset();

        clippedRegion.x += xOffset;
        clippedRegion.width -= xOffset;

        int yOffset = param.getSubsamplingYOffset();

        clippedRegion.y += yOffset;
        clippedRegion.height -= yOffset;
      }
    return clippedRegion;
  }

  /**
   * Get the metadata associated with the image being read.  If the
   * reader is set to ignore metadata or does not support reading
   * metadata, or if no metadata is available then null is returned.
   * This method returns metadata associated with the entirety of the
   * image data, whereas getStreamMetadata() returns metadata
   * associated with a frame within a multi-image data stream.
   *
   * This more specific version of getStreamMetadata() can be used to
   * restrict metadata retrieval to specific formats and node names,
   * which can limit the amount of data that needs to be processed.
   *
   * @param formatName the format of metadata requested
   * @param nodeNames a set of Strings specifiying node names to be
   * retrieved
   *
   * @return metadata associated with the image being read, or null
   *
   * @exception IllegalArgumentException if formatName is null
   * @exception IllegalArgumentException if nodeNames is null
   * @exception IOException if a read error occurs
   */
  public IIOMetadata getStreamMetadata (String formatName,
                                        Set nodeNames)
    throws IOException
  {
    if (formatName == null || nodeNames == null)
      throw new IllegalArgumentException ("null argument");

    return getStreamMetadata();
  }

  /**
   * Read the given frame all at once, using default image read
   * parameters, and return a buffered image.
   *
   * The returned image will be formatted according to the
   * currently-preferred image type specifier.
   *
   * Installed read progress listeners, update progress listeners and
   * warning listeners will be notified of read progress, changes in
   * sample sets and warnings respectively.
   *
   * @param the index of the image frame to read
   *
   * @return a buffered image
   *
   * @exception IllegalStateException if input has not been set
   * @exception IndexOutOfBoundsException if the frame index is
   * out-of-bounds
   * @exception IOException if a read error occurs
   */
  public BufferedImage read (int imageIndex)
    throws IOException
  {
    return read (imageIndex, null);
  }

  /**
   * Read the given frame all at once, using the given image read
   * parameters, and return an IIOImage.  The IIOImage will contain a
   * buffered image as returned by getDestination.
   *
   * Installed read progress listeners, update progress listeners and
   * warning listeners will be notified of read progress, changes in
   * sample sets and warnings respectively.
   *
   * The source and destination band settings are checked with a call
   * to checkReadParamBandSettings.
   *
   * @param the index of the image frame to read
   * @param the image read parameters
   *
   * @return an IIOImage
   *
   * @exception IllegalStateException if input has not been set
   * @exception IndexOutOfBoundsException if the frame index is
   * out-of-bounds
   * @exception IllegalArgumentException if param.getSourceBands() and
   * param.getDestinationBands() are incompatible
   * @exception IllegalArgumentException if either the source or
   * destination image regions are empty
   * @exception IOException if a read error occurs
   */
  public IIOImage readAll (int imageIndex,
			   ImageReadParam param)
    throws IOException
  {
    checkReadParamBandSettings (param,
                                param.getSourceBands().length,
                                param.getDestinationBands().length);

    List l = new ArrayList ();

    for (int i = 0; i < getNumThumbnails (imageIndex); i++)
      l.add (readThumbnail(imageIndex, i));

    return new IIOImage (getDestination(param, getImageTypes(imageIndex),
                                        getWidth(imageIndex),
                                        getHeight(imageIndex)),
                         l,
                         getImageMetadata (imageIndex));
  }

  /**
   * Read all image frames all at once, using the given image read
   * parameters iterator, and return an iterator over a collection of
   * IIOImages.  Each IIOImage in the collection will contain a
   * buffered image as returned by getDestination.
   *
   * Installed read progress listeners, update progress listeners and
   * warning listeners will be notified of read progress, changes in
   * sample sets and warnings respectively.
   *
   * Each set of source and destination band settings are checked with
   * a call to checkReadParamBandSettings.
   *
   * @param an iterator over the image read parameters
   *
   * @return an IIOImage
   *
   * @exception IllegalStateException if input has not been set
   * @exception IllegalArgumentException if a non-ImageReadParam is
   * found in params
   * @exception IllegalArgumentException if param.getSourceBands() and
   * param.getDestinationBands() are incompatible
   * @exception IllegalArgumentException if either the source or
   * destination image regions are empty
   * @exception IOException if a read error occurs
   */
  public Iterator readAll (Iterator params)
    throws IOException
  {
    List l = new ArrayList ();
    int index = 0;

    while (params.hasNext())
      {
        if (params != null && ! (params instanceof ImageReadParam))
          throw new IllegalArgumentException ("non-ImageReadParam found");

        l.add (readAll(index++, (ImageReadParam) params.next ()));
      }

    return l.iterator();
  }

  /**
   * Read a rendered image.  This is a more general counterpart to
   * read (int, ImageReadParam).  All image data may not be read
   * before this method returns and so listeners will not necessarily
   * be notified.
   *
   * @param the index of the image frame to read
   * @param the image read parameters
   *
   * @return a rendered image
   *
   * @exception IllegalStateException if input is null
   * @exception IndexOutOfBoundsException if the frame index is
   * out-of-bounds
   * @exception IllegalArgumentException if param.getSourceBands() and
   * param.getDestinationBands() are incompatible
   * @exception IllegalArgumentException if either the source or
   * destination image regions are empty
   * @exception IOException if a read error occurs
   */
  public RenderedImage readAsRenderedImage (int imageIndex,
					    ImageReadParam param)
    throws IOException
  {
    return read (imageIndex, param);
  }

  /**
   * Read the given tile into a buffered image.  If the tile
   * coordinates are out-of-bounds an exception is thrown.  If the
   * image is not tiled then the coordinates 0, 0 are expected and the
   * entire image will be read.
   *
   * @param imageIndex the frame index
   * @param tileX the horizontal tile coordinate
   * @param tileY the vertical tile coordinate
   *
   * @return the contents of the tile as a buffered image
   *
   * @exception IllegalStateException if input is null
   * @exception IndexOutOfBoundsException if the frame index is
   * out-of-bounds
   * @exception IllegalArgumentException if the tile coordinates are
   * out-of-bounds
   * @exception IOException if a read error occurs
   */
  public BufferedImage readTile (int imageIndex, int tileX, int tileY)
    throws IOException
  {
    if (tileX != 0 || tileY != 0)
      throw new IllegalArgumentException ("tileX not 0 or tileY not 0");

    return read (imageIndex);
  }

  /**
   * Read the given tile into a raster containing the raw image data.
   * If the tile coordinates are out-of-bounds an exception is thrown.
   * If the image is not tiled then the coordinates 0, 0 are expected
   * and the entire image will be read.
   *
   * @param imageIndex the frame index
   * @param tileX the horizontal tile coordinate
   * @param tileY the vertical tile coordinate
   *
   * @return the contents of the tile as a raster
   *
   * @exception UnsupportedOperationException if rasters are not
   * supported
   * @exception IllegalStateException if input is null
   * @exception IndexOutOfBoundsException if the frame index is
   * out-of-bounds
   * @exception IllegalArgumentException if the tile coordinates are
   * out-of-bounds
   * @exception IOException if a read error occurs
   */
  public Raster readTileRaster (int imageIndex, int tileX, int tileY)
    throws IOException
  {
    if (!canReadRaster())
      throw new UnsupportedOperationException ("cannot read rasters");

    if (tileX != 0 || tileY != 0)
      throw new IllegalArgumentException ("tileX not 0 or tileY not 0");

    return readRaster (imageIndex, null);
  }

  /**
   * Reset this reader's internal state.
   */
  public void reset ()
  {
    setInput (null, false);
    setLocale (null);
    removeAllIIOReadUpdateListeners ();
    removeAllIIOReadWarningListeners ();
    removeAllIIOReadProgressListeners ();
    clearAbortRequest ();
  }
}