path: root/jeu-test/Lemmini/0.84/src/Extract/GifEncoder.java

package Extract;

import java.awt.image.BufferedImage;
import java.awt.image.ColorModel;
import java.awt.image.IndexColorModel;
import java.io.IOException;
import java.io.OutputStream;

/**  GifEncoder - writes out an image as a GIF.
 *
 * Transparency handling and variable bit size courtesy of Jack Palevich.
 *
 * Some hacks for compatibility with JVM on MacOS by Volker Oth
 *
 * Copyright (C) 1996 by Jef Poskanzer <jef(at)acme.com>.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * Visit the ACME Labs Java page for up-to-date versions of this and other
 * fine Java utilities: http://www.acme.com/java/
 *
 * @author Jef Poskanzer / Volker Oth
 */

public class GifEncoder {

	private boolean interlace = false;
	private int width, height;
	private byte[] pixels;
	private byte[] r, g, b; // the color look-up table
	private int pixelIndex;
	private int numPixels;
	private int transparentPixel = -1; // hpm

	/**
	 *  Constructs a new GifEncoder.
	 * @param width	The image width.
	 * @param height	The image height.
	 * @param pixels	The pixel data.
	 * @param r		The red look-up table.
	 * @param g		The green look-up table.
	 * @param b		The blue look-up table.
	 */
	public GifEncoder(final int width, final int height, final byte[] pixels, final byte[] r,final  byte[] g, final byte[] b) {
		this.width = width;
		this.height = height;
		this.pixels = pixels;
		this.r = r; this.g = g; this.b = b;
		interlace = false;
		pixelIndex = 0;
		numPixels = width*height;
	}

	/**
	 * Constructs a new GifEncoder using an 8-bit AWT Image.
	 * The image is assumed to be fully loaded.
	 * @param img Image
	 */
	public GifEncoder(final BufferedImage img) {
		width = img.getWidth(null);
		height = img.getHeight(null);
		pixels = new byte[width * height];
		/* VO: Pixelgrabber seems to behave differently on MacOS (uses first of two identical
		 * palette entries instead of the original one.
		 * Therefore we need to "grab" the pixels manually */
		ColorModel cm = img.getColorModel();
		if (cm instanceof IndexColorModel) {
			IndexColorModel icm = (IndexColorModel)cm;
			setTransparentPixel(icm.getTransparentPixel());
		} else
			throw new IllegalArgumentException("Image must be 8-bit");

		/* VO: manual pixel grabbing */
		for (int y=0; y<height; y++) {
			int line = y*width;
			for (int x=0; x<width; x++) {
				int colIdx = img.getRaster().getDataBuffer().getElem(x+line);
				pixels[line+x] = (byte)colIdx;
			}
		}

		IndexColorModel m = (IndexColorModel)cm;
		int mapSize = m.getMapSize();
		r = new byte[mapSize];
		g = new byte[mapSize];
		b = new byte[mapSize];
		m.getReds(r);
		m.getGreens(g);
		m.getBlues(b);
		interlace = false;
		pixelIndex = 0;
		numPixels = width*height;
	}

	/**
	 * Saves the image as a GIF file.
	 * @param out Output stream to write to
	 * @throws IOException
	 */
	public void write(final OutputStream out) throws IOException {
		// Figure out how many bits to use.
		int numColors = r.length;
		int BitsPerPixel;
		if (numColors<=2)
			BitsPerPixel = 1;
		else if (numColors<=4)
			BitsPerPixel = 2;
		else if (numColors<=16)
			BitsPerPixel = 4;
		else
			BitsPerPixel = 8;

		int ColorMapSize = 1 << BitsPerPixel;
		byte[] reds = new byte[ColorMapSize];
		byte[] grns = new byte[ColorMapSize];
		byte[] blus = new byte[ColorMapSize];
		for (int i=0; i<numColors; i++) {
			reds[i] = r[i];
			grns[i] = g[i];
			blus[i] = b[i];
		}
		// hpm
		GIFEncode(out, width, height, interlace, (byte) 0,
				getTransparentPixel(), BitsPerPixel, reds, grns, blus);
	}

	// hpm
	/**
	 * Set transparent pixel color (palette index)
	 * @param pixel transparent pixel color (palette index)
	 */
	public void setTransparentPixel(final int pixel) {
		transparentPixel = pixel;
	}

	// hpm
	/**
	 * Get transparent pixel color (palette index)
	 * @return transparent pixel color (palette index)
	 */
	public int getTransparentPixel() {
		return transparentPixel;
	}

	static void writeString(final OutputStream out, final String str) throws IOException {
		byte[] buf = str.getBytes();
		out.write(buf);
	}

	// Adapted from ppmtogif, which is based on GIFENCOD by David
	// Rowley <mgardi@watdscu.waterloo.edu>.  Lempel-Zim compression
	// based on "compress".

	void GIFEncode(final OutputStream outs, final int Width, final int Height, final boolean Interlace, final byte Background,
			final int Transparent, final int BitsPerPixel, final byte[] Red, final byte[] Green, final byte[] Blue ) throws IOException {
		byte B;
		int LeftOfs, TopOfs;
		int ColorMapSize;
		int InitCodeSize;
		int i;

		ColorMapSize = 1 << BitsPerPixel;
		LeftOfs = TopOfs = 0;

		// The initial code size
		if ( BitsPerPixel <= 1 )
			InitCodeSize = 2;
		else
			InitCodeSize = BitsPerPixel;

		// Write the Magic header
		writeString( outs, "GIF89a" );

		// Write out the screen width and height
		Putword( Width, outs );
		Putword( Height, outs );

		// Indicate that there is a global colour map
		B = (byte) 0x80;		// Yes, there is a color map
		// OR in the resolution
		B |= (byte) ( ( 8 - 1 ) << 4 );
		// Not sorted
		// OR in the Bits per Pixel
		B |= (byte) ( ( BitsPerPixel - 1 ) );

		// Write it out
		Putbyte( B, outs );

		// Write out the Background colour
		Putbyte( Background, outs );

		// Pixel aspect ratio - 1:1.
		//Putbyte( (byte) 49, outs );
		// Java's GIF reader currently has a bug, if the aspect ratio byte is
		// not zero it throws an ImageFormatException.  It doesn't know that
		// 49 means a 1:1 aspect ratio.  Well, whatever, zero works with all
		// the other decoders I've tried so it probably doesn't hurt.
		Putbyte( (byte) 0, outs );

		// Write out the Global Colour Map
		for ( i = 0; i < ColorMapSize; ++i ) {
			Putbyte( Red[i], outs );
			Putbyte( Green[i], outs );
			Putbyte( Blue[i], outs );
		}

		// Write out extension for transparent colour index, if necessary.
		if ( Transparent != -1 ) {
			Putbyte( (byte) '!', outs );
			Putbyte( (byte) 0xf9, outs );
			Putbyte( (byte) 4, outs );
			Putbyte( (byte) 1, outs );
			Putbyte( (byte) 0, outs );
			Putbyte( (byte) 0, outs );
			Putbyte( (byte) Transparent, outs );
			Putbyte( (byte) 0, outs );
		}

		// Write an Image separator
		Putbyte( (byte) ',', outs );

		// Write the Image header
		Putword( LeftOfs, outs );
		Putword( TopOfs, outs );
		Putword( Width, outs );
		Putword( Height, outs );

		// Write out whether or not the image is interlaced
		if ( Interlace )
			Putbyte( (byte) 0x40, outs );
		else
			Putbyte( (byte) 0x00, outs );

		// Write out the initial code size
		Putbyte( (byte) InitCodeSize, outs );

		// Go and actually compress the data
		compress( InitCodeSize+1, outs );

		// Write out a Zero-length packet (to end the series)
		Putbyte( (byte) 0, outs );

		// Write the GIF file terminator
		Putbyte( (byte) ';', outs );
	}


	static final int EOF = -1;

	// Return the next pixel from the image
	int GIFNextPixel() {
		if (pixelIndex==numPixels)
			return EOF;
		else
			return pixels[pixelIndex++] & 0xff;
	}


	// Write out a word to the GIF file
	void Putword( final int w, final OutputStream outs ) throws IOException {
		Putbyte( (byte) ( w & 0xff ), outs );
		Putbyte( (byte) ( ( w >> 8 ) & 0xff ), outs );
	}

	// Write out a byte to the GIF file
	void Putbyte( final byte b, final OutputStream outs ) throws IOException {
		outs.write( b );
	}


	// GIFCOMPR.C       - GIF Image compression routines
	//
	// Lempel-Ziv compression based on 'compress'.  GIF modifications by
	// David Rowley (mgardi@watdcsu.waterloo.edu)

	// General DEFINEs

	private static final int BITS = 12;

	private static final int HSIZE = 5003;		// 80% occupancy

	// GIF Image compression - modified 'compress'
	//
	// Based on: compress.c - File compression ala IEEE Computer, June 1984.
	//
	// By Authors:  Spencer W. Thomas      (decvax!harpo!utah-cs!utah-gr!thomas)
	//              Jim McKie              (decvax!mcvax!jim)
	//              Steve Davies           (decvax!vax135!petsd!peora!srd)
	//              Ken Turkowski          (decvax!decwrl!turtlevax!ken)
	//              James A. Woods         (decvax!ihnp4!ames!jaw)
	//              Joe Orost              (decvax!vax135!petsd!joe)

	private int n_bits;					// number of bits/code
	private int maxbits = BITS;			// user settable max # bits/code
	private int maxcode;					// maximum code, given n_bits
	private int maxmaxcode = 1 << BITS; // should NEVER generate this code

	final int MAXCODE( final int n_bits ) {
		return ( 1 << n_bits ) - 1;
	}

	private int[] htab = new int[HSIZE];
	private int[] codetab = new int[HSIZE];

	private int hsize = HSIZE;			// for dynamic table sizing

	private int free_ent = 0;			// first unused entry

	// block compression parameters -- after all codes are used up,
	// and compression rate changes, start over.
	private boolean clear_flg = false;

	// Algorithm:  use open addressing double hashing (no chaining) on the
	// prefix code / next character combination.  We do a variant of Knuth's
	// algorithm D (vol. 3, sec. 6.4) along with G. Knott's relatively-prime
	// secondary probe.  Here, the modular division first probe is gives way
	// to a faster exclusive-or manipulation.  Also do block compression with
	// an adaptive reset, whereby the code table is cleared when the compression
	// ratio decreases, but after the table fills.  The variable-length output
	// codes are re-sized at this point, and a special CLEAR code is generated
	// for the decompressor.  Late addition:  construct the table according to
	// file size for noticeable speed improvement on small files.  Please direct
	// questions about this implementation to ames!jaw.

	private int g_init_bits;

	private int ClearCode;
	private int EOFCode;

	void compress( final int init_bits, final OutputStream outs ) throws IOException {
		int fcode;
		int i /* = 0 */;
		int c;
		int ent;
		int disp;
		int hsize_reg;
		int hshift;

		// Set up the globals:  g_init_bits - initial number of bits
		g_init_bits = init_bits;

		// Set up the necessary values
		clear_flg = false;
		n_bits = g_init_bits;
		maxcode = MAXCODE( n_bits );

		ClearCode = 1 << ( init_bits - 1 );
		EOFCode = ClearCode + 1;
		free_ent = ClearCode + 2;

		char_init();

		ent = GIFNextPixel();

		hshift = 0;
		for ( fcode = hsize; fcode < 65536; fcode *= 2 )
			++hshift;
		hshift = 8 - hshift;			// set hash code range bound

		hsize_reg = hsize;
		cl_hash( hsize_reg );	// clear hash table

		output( ClearCode, outs );

		outer_loop:
			while ( (c = GIFNextPixel()) != EOF ) {
				fcode = ( c << maxbits ) + ent;
				i = ( c << hshift ) ^ ent;		// xor hashing

				if ( htab[i] == fcode ) {
					ent = codetab[i];
					continue;
				}
				else if ( htab[i] >= 0 ) {	// non-empty slot
					disp = hsize_reg - i;	// secondary hash (after G. Knott)
					if ( i == 0 )
						disp = 1;
					do {
						if ( (i -= disp) < 0 )
							i += hsize_reg;

						if ( htab[i] == fcode ) {
							ent = codetab[i];
							continue outer_loop;
						}
					}
					while ( htab[i] >= 0 );
				}
				output( ent, outs );
				ent = c;
				if ( free_ent < maxmaxcode ) {
					codetab[i] = free_ent++;	// code -> hashtable
					htab[i] = fcode;
				} else
					cl_block( outs );
			}
		// Put out the final code.
		output( ent, outs );
		output( EOFCode, outs );
	}

	// output
	//
	// OutputDialog the given code.
	// Inputs:
	//      code:   A n_bits-bit integer.  If == -1, then EOF.  This assumes
	//              that n_bits =< wordsize - 1.
	// Outputs:
	//      Outputs code to the file.
	// Assumptions:
	//      Chars are 8 bits long.
	// Algorithm:
	//      Maintain a BITS character long buffer (so that 8 codes will
	// fit in it exactly).  Use the VAX insv instruction to insert each
	// code in turn.  When the buffer fills up empty it and start over.

	private int cur_accum = 0;
	private int cur_bits = 0;

	private final int MASKS[] = { 
			0x0000, 0x0001, 0x0003, 0x0007, 0x000F,
			0x001F, 0x003F, 0x007F, 0x00FF,
			0x01FF, 0x03FF, 0x07FF, 0x0FFF,
			0x1FFF, 0x3FFF, 0x7FFF, 0xFFFF
	};

	void output( final int code, final OutputStream outs ) throws IOException {
		cur_accum &= MASKS[cur_bits];

		if ( cur_bits > 0 )
			cur_accum |= ( code << cur_bits );
		else
			cur_accum = code;

		cur_bits += n_bits;

		while ( cur_bits >= 8 ) {
			char_out( (byte) ( cur_accum & 0xff ), outs );
			cur_accum >>= 8;
			cur_bits -= 8;
		}

		// If the next entry is going to be too big for the code size,
		// then increase it, if possible.
		if ( free_ent > maxcode || clear_flg ) {
			if ( clear_flg ) {
				maxcode = MAXCODE(n_bits = g_init_bits);
				clear_flg = false;
			} else {
				++n_bits;
				if ( n_bits == maxbits )
					maxcode = maxmaxcode;
				else
					maxcode = MAXCODE(n_bits);
			}
		}

		if ( code == EOFCode ) {
			// At EOF, write the rest of the buffer.
			while ( cur_bits > 0 ) {
				char_out( (byte) ( cur_accum & 0xff ), outs );
				cur_accum >>= 8;
		cur_bits -= 8;
			}

			flush_char( outs );
		}
	}

	// Clear out the hash table

	// table clear for block compress
	void cl_block( final OutputStream outs ) throws IOException {
		cl_hash( hsize );
		free_ent = ClearCode + 2;
		clear_flg = true;

		output( ClearCode, outs );
	}

	// reset code table
	void cl_hash( final int hsize ) {
		for ( int i = 0; i < hsize; ++i )
			htab[i] = -1;
	}

	// GIF Specific routines

	// Number of characters so far in this 'packet'
	private int a_count;

	// Set up the 'byte output' routine
	void char_init() {
		a_count = 0;
	}

	// Define the storage for the packet accumulator
	private byte[] accum = new byte[256];

	// Add a character to the end of the current packet, and if it is 254
	// characters, flush the packet to disk.
	void char_out(final  byte c, final OutputStream outs ) throws IOException {
		accum[a_count++] = c;
		if ( a_count >= 254 )
			flush_char( outs );
	}

	// Flush the packet to disk, and reset the accumulator
	void flush_char( final OutputStream outs ) throws IOException {
		if ( a_count > 0 ) {
			outs.write( a_count );
			outs.write( accum, 0, a_count );
			a_count = 0;
		}
	}

}

class GifEncoderHashitem {
	public int rgb;
	public int count;
	public int index;
	public boolean isTransparent;

	public GifEncoderHashitem(final int rgb, final int count, final int index, final boolean isTransparent) {
		this.rgb = rgb;
		this.count = count;
		this.index = index;
		this.isTransparent = isTransparent;
	}

}