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Diffstat (limited to 'java/ImageProcessing/framework/GifEncoder.java')
-rw-r--r-- | java/ImageProcessing/framework/GifEncoder.java | 693 |
1 files changed, 0 insertions, 693 deletions
diff --git a/java/ImageProcessing/framework/GifEncoder.java b/java/ImageProcessing/framework/GifEncoder.java deleted file mode 100644 index 91a3927d95d..00000000000 --- a/java/ImageProcessing/framework/GifEncoder.java +++ /dev/null @@ -1,693 +0,0 @@ -// GifEncoder - write out an image as a GIF -// -// Transparency handling and variable bit size courtesy of Jack Palevich. -// -// Copyright (C) 1996 by Jef Poskanzer <jef@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/ - -package imaging.framework; - -import java.util.*; -import java.io.*; -import java.awt.Image; -import java.awt.image.*; - -/// Write out an image as a GIF. -// <P> -// <A HREF="/resources/classes/Acme/JPM/Encoders/GifEncoder.java">Fetch the software.</A><BR> -// <A HREF="/resources/classes/Acme.tar.Z">Fetch the entire Acme package.</A> -// <P> -// @see ToGif - -public class GifEncoder extends ImageEncoder - { - - private boolean interlace = false; - - /// Constructor from Image. - // @param img The image to encode. - // @param out The stream to write the GIF to. - public GifEncoder( Image img, OutputStream out ) throws IOException - { - super( img, out ); - } - - /// Constructor from Image with interlace setting. - // @param img The image to encode. - // @param out The stream to write the GIF to. - // @param interlace Whether to interlace. - public GifEncoder( Image img, OutputStream out, boolean interlace ) throws IOException - { - super( img, out ); - this.interlace = interlace; - } - - /// Constructor from ImageProducer. - // @param prod The ImageProducer to encode. - // @param out The stream to write the GIF to. - public GifEncoder( ImageProducer prod, OutputStream out ) throws IOException - { - super( prod, out ); - } - - /// Constructor from ImageProducer with interlace setting. - // @param prod The ImageProducer to encode. - // @param out The stream to write the GIF to. - public GifEncoder( ImageProducer prod, OutputStream out, boolean interlace ) throws IOException - { - super( prod, out ); - this.interlace = interlace; - } - - - int width, height; - int[][] rgbPixels; - - void encodeStart( int width, int height ) throws IOException - { - this.width = width; - this.height = height; - rgbPixels = new int[height][width]; - } - - void encodePixels( - int x, int y, int w, int h, int[] rgbPixels, int off, int scansize ) - throws IOException - { - // Save the pixels. - for ( int row = 0; row < h; ++row ) - System.arraycopy( - rgbPixels, row * scansize + off, - this.rgbPixels[y + row], x, w ); - - } - - IntHashtable colorHash; - - void encodeDone() throws IOException - { - int transparentIndex = -1; - int transparentRgb = -1; - // Put all the pixels into a hash table. - colorHash = new IntHashtable(); - int index = 0; - for ( int row = 0; row < height; ++row ) - { - int rowOffset = row * width; - for ( int col = 0; col < width; ++col ) - { - int rgb = rgbPixels[row][col]; - boolean isTransparent = ( ( rgb >>> 24 ) < 0x80 ); - if ( isTransparent ) - { - if ( transparentIndex < 0 ) - { - // First transparent color; remember it. - transparentIndex = index; - transparentRgb = rgb; - } - else if ( rgb != transparentRgb ) - { - // A second transparent color; replace it with - // the first one. - rgbPixels[row][col] = rgb = transparentRgb; - } - } - GifEncoderHashitem item = - (GifEncoderHashitem) colorHash.get( rgb ); - if ( item == null ) - { - if ( index >= 256 ) - throw new IOException( "too many colors for a GIF" ); - item = new GifEncoderHashitem( - rgb, 1, index, isTransparent ); - ++index; - colorHash.put( rgb, item ); - } - else - ++item.count; - } - } - - // Figure out how many bits to use. - int logColors; - if ( index <= 2 ) - logColors = 1; - else if ( index <= 4 ) - logColors = 2; - else if ( index <= 16 ) - logColors = 4; - else - logColors = 8; - - // Turn colors into colormap entries. - int mapSize = 1 << logColors; - byte[] reds = new byte[mapSize]; - byte[] grns = new byte[mapSize]; - byte[] blus = new byte[mapSize]; - for ( Enumeration e = colorHash.elements(); e.hasMoreElements(); ) - { - GifEncoderHashitem item = (GifEncoderHashitem) e.nextElement(); - reds[item.index] = (byte) ( ( item.rgb >> 16 ) & 0xff ); - grns[item.index] = (byte) ( ( item.rgb >> 8 ) & 0xff ); - blus[item.index] = (byte) ( item.rgb & 0xff ); - } - - GIFEncode( - out, width, height, interlace, (byte) 0, transparentIndex, - logColors, reds, grns, blus ); - } - - byte GetPixel( int x, int y ) throws IOException - { - GifEncoderHashitem item = - (GifEncoderHashitem) colorHash.get( rgbPixels[y][x] ); - if ( item == null ) - throw new IOException( "color not found" ); - return (byte) item.index; - } - - static void writeString( OutputStream out, String str ) throws IOException - { - int len = str.length(); - byte[] buf = new byte[len]; - str.getBytes( 0, len, buf, 0 ); - out.write( buf ); - } - - // Adapted from ppmtogif, which is based on GIFENCOD by David - // Rowley <mgardi@watdscu.waterloo.edu>. Lempel-Zim compression - // based on "compress". - - int Width, Height; - boolean Interlace; - int curx, cury; - int CountDown; - int Pass = 0; - - void GIFEncode( - OutputStream outs, int Width, int Height, boolean Interlace, byte Background, int Transparent, int BitsPerPixel, byte[] Red, byte[] Green, byte[] Blue ) - throws IOException - { - byte B; - int LeftOfs, TopOfs; - int ColorMapSize; - int InitCodeSize; - int i; - - this.Width = Width; - this.Height = Height; - this.Interlace = Interlace; - ColorMapSize = 1 << BitsPerPixel; - LeftOfs = TopOfs = 0; - - // Calculate number of bits we are expecting - CountDown = Width * Height; - - // Indicate which pass we are on (if interlace) - Pass = 0; - - // The initial code size - if ( BitsPerPixel <= 1 ) - InitCodeSize = 2; - else - InitCodeSize = BitsPerPixel; - - // Set up the current x and y position - curx = 0; - cury = 0; - - // 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 ); - } - - // Bump the 'curx' and 'cury' to point to the next pixel - void BumpPixel() - { - // Bump the current X position - ++curx; - - // If we are at the end of a scan line, set curx back to the beginning - // If we are interlaced, bump the cury to the appropriate spot, - // otherwise, just increment it. - if ( curx == Width ) - { - curx = 0; - - if ( ! Interlace ) - ++cury; - else - { - switch( Pass ) - { - case 0: - cury += 8; - if ( cury >= Height ) - { - ++Pass; - cury = 4; - } - break; - - case 1: - cury += 8; - if ( cury >= Height ) - { - ++Pass; - cury = 2; - } - break; - - case 2: - cury += 4; - if ( cury >= Height ) - { - ++Pass; - cury = 1; - } - break; - - case 3: - cury += 2; - break; - } - } - } - } - - static final int EOF = -1; - - // Return the next pixel from the image - int GIFNextPixel() throws IOException - { - byte r; - - if ( CountDown == 0 ) - return EOF; - - --CountDown; - - r = GetPixel( curx, cury ); - - BumpPixel(); - - return r & 0xff; - } - - // Write out a word to the GIF file - void Putword( int w, 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( byte b, 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 - - static final int BITS = 12; - - 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) - - int n_bits; // number of bits/code - int maxbits = BITS; // user settable max # bits/code - int maxcode; // maximum code, given n_bits - int maxmaxcode = 1 << BITS; // should NEVER generate this code - - final int MAXCODE( int n_bits ) - { - return ( 1 << n_bits ) - 1; - } - - int[] htab = new int[HSIZE]; - int[] codetab = new int[HSIZE]; - - int hsize = HSIZE; // for dynamic table sizing - - int free_ent = 0; // first unused entry - - // block compression parameters -- after all codes are used up, - // and compression rate changes, start over. - 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. - - int g_init_bits; - - int ClearCode; - int EOFCode; - - void compress( int init_bits, 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 - // - // Output 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. - - int cur_accum = 0; - int cur_bits = 0; - - int masks[] = { 0x0000, 0x0001, 0x0003, 0x0007, 0x000F, - 0x001F, 0x003F, 0x007F, 0x00FF, - 0x01FF, 0x03FF, 0x07FF, 0x0FFF, - 0x1FFF, 0x3FFF, 0x7FFF, 0xFFFF }; - - void output( int code, 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( OutputStream outs ) throws IOException - { - cl_hash( hsize ); - free_ent = ClearCode + 2; - clear_flg = true; - - output( ClearCode, outs ); - } - - // reset code table - void cl_hash( int hsize ) - { - for ( int i = 0; i < hsize; ++i ) - htab[i] = -1; - } - - // GIF Specific routines - - // Number of characters so far in this 'packet' - int a_count; - - // Set up the 'byte output' routine - void char_init() - { - a_count = 0; - } - - // Define the storage for the packet accumulator - 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( byte c, 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( 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( int rgb, int count, int index, boolean isTransparent ) - { - this.rgb = rgb; - this.count = count; - this.index = index; - this.isTransparent = isTransparent; - } - - } |