dxtcompressor.java

来自「world wind java sdk 源码」· Java 代码 · 共 52 行

/* Copyright (C) 2001, 2008 United States Government as represented by
the Administrator of the National Aeronautics and Space Administration.
All Rights Reserved.
*/
package gov.nasa.worldwind.formats.dds;

/**
 * The <code>DXTCompressor</code> interface will compress an in-memory image using one of the DXT block compression
 * schemes. The details of each block compression scheme is handled by the implementation.
 * 
 * @author dcollins
 * @version $Id: DXTCompressor.java 8915 2009-02-19 21:31:36Z dcollins $
 */
public interface DXTCompressor
{
    /**
     * Returns the DXT format constant associated with this compressor.
     *
     * @see gov.nasa.worldwind.formats.dds.DDSConstants
     *
     * @return DXT format for this compressor.
     */
    int getDXTFormat();

    /**
     * Returns the compressed size in bytes of the specified <code>image</code>.
     *
     * @param image the image to compute the compressed size for.
     * @param attributes the attributes that may affect the compressed size.
     *
     * @return compressed size in bytes of the specified image.
     * @throws IllegalArgumentException if either <code>image</code> or <code>attributes</code> is null.
     */
    int getCompressedSize(java.awt.image.BufferedImage image, DXTCompressionAttributes attributes);

    /**
     * Encodes the specified <code>image</code> image into a compressed DXT codec, and writes the compressed bytes
     * to the specified <code>buffer</code>. The buffer should be allocated with enough space to hold the compressed
     * output. The correct size should be computed by calling <code>getCompressedSize(image, attributes)</code>.
     *
     * @param image the image to compress.
     * @param attributes the attributes that may affect the compression.
     * @param buffer the buffer that will receive the compressed output.
     *
     * @see #getCompressedSize(java.awt.image.BufferedImage, DXTCompressionAttributes)
     * @throws IllegalArgumentException if any of <code>image</code>, <code>attributes</code>, or
     *                                  <code>buffer</code> are null.
     */
    void compressImage(java.awt.image.BufferedImage image, DXTCompressionAttributes attributes,
        java.nio.ByteBuffer buffer);
}