ddscompressor.java

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/* 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;

import gov.nasa.worldwind.util.*;

import java.awt.image.*;

/**
 * <code>DDSCompressor</code> will convert an in-memory image into a DDS file encoded with one of the DXT block
 * compression schemes. If the caller wants to encode using a certain type of DXT compression,
 * <code>DDSCompressor</code> provides the appropriate methods to do that. Otherwise, <code>DDSCompressor</code> will
 * choose the DXT compression scheme that best suits the source image.
 * <p>
 * Each compression method accepts a reference to a <code>DXTCompressionAttributes</code>. This compressor will perform
 * the appropriate actions according to the attributes, such as building mip maps and converting the source image to a
 * premultiplied alpha format.
 *
 * @author dcollins
 * @version $Id: DDSCompressor.java 9600 2009-03-22 20:04:40Z tgaskins $
 */
public class DDSCompressor
{
    /**
     * Creates a new <code>DDSCompressor</code>, but otherwise does nothing.
     */
    public DDSCompressor()
    {
    }

    /**
     * Convenience method to convert the specified <code>imageBuffer</code> to DDS according to the default attributes.
     * The bytes in <code>imageBuffer</code> must be readable by {@link javax.imageio.ImageIO}. Once the image data is
     * read, this is equivalent to calling {#compressImage(java.awt.image.BufferedImage)} with the BufferedImage
     * created by ImageIO. If the image data is not in a format understood by ImageIO, this method will return null.
     *
     * @param imageBuffer image file data to convert to the DDS file format.
     *
     * @return little endian ordered ByteBuffer containing the dds file bytes, or null if the bytes in
     *         <code>imageBuffer</code> are not in a format understood by ImageIO.
     * @throws java.io.IOException if the bytes in <code>imageBuffer</code> are in a format understood by ImageIO, but
     *         the image data cannot be read by ImageIO.
     * @throws IllegalArgumentException if <code>imageBuffer</code> is null.
     */
    public static java.nio.ByteBuffer compressImageBuffer(java.nio.ByteBuffer imageBuffer) throws java.io.IOException
    {
        if (imageBuffer == null)
        {
            String message = Logging.getMessage("nullValue.Image");
            Logging.logger().severe(message);
            throw new IllegalArgumentException(message);
        }

        java.io.InputStream inputStream = WWIO.getInputStreamFromByteBuffer(imageBuffer);
        java.awt.image.BufferedImage image = javax.imageio.ImageIO.read(inputStream);
        if (image == null)
        {
            return null;
        }

        return compressImage(image);
    }

    /**
     * Convenience method to convert the specified image <code>file</code> to DDS according to the default attributes.
     * The <code>file</code> must be readable by {@link javax.imageio.ImageIO}. Once the file is read, this is
     * equivalent to calling {#compressImage(java.awt.image.BufferedImage)} with the BufferedImage created by ImageIO.
     * If the file is not in a format understood by ImageIO, this method will return null.
     *
     * @param file image file to convert to the DDS file format.
     *
     * @return little endian ordered ByteBuffer containing the dds file bytes, or null if the <code>file</code> is not
     *         in a format understood by ImageIO.
     * @throws java.io.IOException if <code>file</code> is in a format understood by ImageIO, but the image data
     *         cannot be read by ImageIO.
     * @throws IllegalArgumentException if <code>file</code> is null, does not exist, or read permission is not
     *                                  allowed on the <code>file</code>.
     */
    public static java.nio.ByteBuffer compressImageFile(java.io.File file) throws java.io.IOException
    {
        if (file == null)
        {
            String message = Logging.getMessage("nullValue.FileIsNull");
            Logging.logger().severe(message);
            throw new IllegalArgumentException(message);
        }

        if (!file.exists() || !file.canRead())
        {
            String message = Logging.getMessage("DDSConverter.NoFileOrNoPermission");
            Logging.logger().severe(message);
            throw new IllegalArgumentException(message);
        }

        java.awt.image.BufferedImage image = javax.imageio.ImageIO.read(file);
        if (image == null)
        {
            return null;
        }

        return compressImage(image);
    }

    /**
     * Convenience method to convert the specified <code>image</code> to DDS according to the default attributes. This
     * will choose the DXT compression format best suited for the image type.
     *
     * @param image image to convert to the DDS file format.
     *
     * @return little endian ordered ByteBuffer containing the dds file bytes.
     * @throws IllegalArgumentException if <code>image</code> is null, or if <code>image</code> has non power of two
     *                                  dimensions.
     */
    public static java.nio.ByteBuffer compressImage(java.awt.image.BufferedImage image)
    {
        if (image == null)
        {
            String message = Logging.getMessage("nullValue.ImageIsNull");
            Logging.logger().severe(message);
            throw new IllegalArgumentException(message);
        }
        if (!WWMath.isPowerOfTwo(image.getWidth()) || !WWMath.isPowerOfTwo(image.getHeight()))
        {
            String message = Logging.getMessage("generic.InvalidImageSize", image.getWidth(), image.getHeight());
            Logging.logger().severe(message);
            throw new IllegalArgumentException(message);
        }

        DDSCompressor compressor = new DDSCompressor();
        DXTCompressionAttributes attributes = new DXTCompressionAttributes();
        attributes.setBuildMipmaps(true); // Always build mipmaps.
        attributes.setPremultiplyAlpha(true); // Always create premultiplied alpha format files..
        attributes.setDXTFormat(0); // Allow the DDSCompressor to choose the appropriate DXT format.
        return compressor.compressImage(image, attributes);
    }

    /**
     * Convert the specified <code>image</code> to DDS according to the <code>attributes</code>. If the caller
     * specified a DXT format in the attributes, then we return a compressor matching that format. Otherwise, we
     * choose one automatically from the image type. If no choice can be made from the image type, we default to using
     * a DXT3 compressor.
     *
     * @param image image to convert to the DDS file format.
     * @param attributes attributes that will control the compression.
     *
     * @return buffer little endian ordered ByteBuffer containing the dds file bytes.
     * @throws IllegalArgumentException if either <code>image</code> or <code>attributes</code> are null, or if
     *                                  <code>image</code> has non power of two dimensions.
     */
    public java.nio.ByteBuffer compressImage(java.awt.image.BufferedImage image, DXTCompressionAttributes attributes)
    {
        if (image == null)
        {
            String message = Logging.getMessage("nullValue.ImageIsNull");
            Logging.logger().severe(message);
            throw new IllegalArgumentException(message);
        }
        if (!WWMath.isPowerOfTwo(image.getWidth()) || !WWMath.isPowerOfTwo(image.getHeight()))
        {
            String message = Logging.getMessage("generic.InvalidImageSize", image.getWidth(), image.getHeight());
            Logging.logger().severe(message);
            throw new IllegalArgumentException(message);
        }
        if (attributes == null)
        {
            String message = Logging.getMessage("nullValue.AttributesIsNull");
            Logging.logger().severe(message);
            throw new IllegalArgumentException(message);
        }

        DXTCompressor compressor = this.getDXTCompressor(image, attributes);
        return this.doCompressImage(compressor, image, attributes);
    }

    /**
     * Convert the specified <code>image</code> to DDS using the DXT1 codec, and otherwise according to the
     * <code>attributes</code>.
     *
     * @param image image to convert to the DDS file format using the DXT1 codec.
     * @param attributes attributes that will control the compression.
     *
     * @return buffer little endian ordered ByteBuffer containing the dds file bytes.
     * @throws IllegalArgumentException if either <code>image</code> or <code>attributes</code> are null, or if
     *                                  <code>image</code> has non power of two dimensions.
     */
    public java.nio.ByteBuffer compressImageDXT1(java.awt.image.BufferedImage image,
        DXTCompressionAttributes attributes)
    {
        if (image == null)
        {
            String message = Logging.getMessage("nullValue.ImageIsNull");
            Logging.logger().severe(message);
            throw new IllegalArgumentException(message);
        }
        if (!WWMath.isPowerOfTwo(image.getWidth()) || !WWMath.isPowerOfTwo(image.getHeight()))
        {
            String message = Logging.getMessage("generic.InvalidImageSize", image.getWidth(), image.getHeight());
            Logging.logger().severe(message);
            throw new IllegalArgumentException(message);
        }
        if (attributes == null)
        {
            String message = Logging.getMessage("nullValue.AttributesIsNull");
            Logging.logger().severe(message);
            throw new IllegalArgumentException(message);
        }

        DXT1Compressor compressor = new DXT1Compressor();
        return this.doCompressImage(compressor, image, attributes);
    }

    /**
     * Convert the specified <code>image</code> to DDS using the DXT3 codec, and otherwise according to the
     * <code>attributes</code>.
     *
     * @param image image to convert to the DDS file format using the DXT3 codec.