src/java.desktop/share/classes/com/sun/imageio/plugins/tiff/TIFFT4Compressor.java - platform/libcore - Git at Google

 /*
  * Copyright (c) 2005, 2016, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License version 2 only, as
  * published by the Free Software Foundation.  Oracle designates this
  * particular file as subject to the "Classpath" exception as provided
  * by Oracle in the LICENSE file that accompanied this code.
  *
  * This code is distributed in the hope that it will be useful, but WITHOUT
  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  * version 2 for more details (a copy is included in the LICENSE file that
  * accompanied this code).
  *
  * You should have received a copy of the GNU General Public License version
  * 2 along with this work; if not, write to the Free Software Foundation,
  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  *
  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  * or visit www.oracle.com if you need additional information or have any
  * questions.
  */
 package com.sun.imageio.plugins.tiff;

 import javax.imageio.plugins.tiff.BaselineTIFFTagSet;
 import javax.imageio.plugins.tiff.TIFFField;
 import javax.imageio.plugins.tiff.TIFFTag;
 import java.io.IOException;
 import javax.imageio.IIOException;
 import javax.imageio.metadata.IIOMetadata;

 public class TIFFT4Compressor extends TIFFFaxCompressor {

     private boolean is1DMode = false;
     private boolean isEOLAligned = false;

     public TIFFT4Compressor() {
         super("CCITT T.4", BaselineTIFFTagSet.COMPRESSION_CCITT_T_4, true);
     }

     /**
      * Sets the value of the {@code metadata} field.
      *
      * <p> The implementation in this class also sets local options
      * from the T4_OPTIONS field if it exists, and if it doesn't, adds
      * it with default values.</p>
      *
      * @param metadata the {@code IIOMetadata} object for the
      * image being written.
      *
      * @see #getMetadata()
      */
     public void setMetadata(IIOMetadata metadata) {
         super.setMetadata(metadata);

         if (metadata instanceof TIFFImageMetadata) {
             TIFFImageMetadata tim = (TIFFImageMetadata)metadata;
             TIFFField f = tim.getTIFFField(BaselineTIFFTagSet.TAG_T4_OPTIONS);
             if (f != null) {
                 int options = f.getAsInt(0);
                 is1DMode = (options & 0x1) == 0;
                 isEOLAligned = (options & 0x4) == 0x4;
             } else {
                 long[] oarray = new long[1];
                 oarray[0] = (isEOLAligned ? 0x4 : 0x0) |
                     (is1DMode ? 0x0 : 0x1);

                 BaselineTIFFTagSet base = BaselineTIFFTagSet.getInstance();
                 TIFFField T4Options =
                   new TIFFField(base.getTag(BaselineTIFFTagSet.TAG_T4_OPTIONS),
                                 TIFFTag.TIFF_LONG,
                                 1,
                                 oarray);
                 tim.rootIFD.addTIFFField(T4Options);
             }
         }
     }

     /**
      * Encode a buffer of data using CCITT T.4 Compression also known as
      * Group 3 facsimile compression.
      *
      * @param is1DMode     Whether to perform one-dimensional encoding.
      * @param isEOLAligned Whether EOL bit sequences should be padded.
      * @param data         The row of data to compress.
      * @param lineStride   Byte step between the same sample in different rows.
      * @param colOffset    Bit offset within first {@code data[rowOffset]}.
      * @param width        Number of bits in the row.
      * @param height       Number of rows in the buffer.
      * @param compData     The compressed data.
      *
      * @return The number of bytes saved in the compressed data array.
      */
     public int encodeT4(boolean is1DMode,
                         boolean isEOLAligned,
                         byte[] data,
                         int lineStride,
                         int colOffset,
                         int width,
                         int height,
                         byte[] compData)
     {
         //
         // ao, a1, a2 are bit indices in the current line
         // b1 and b2  are bit indices in the reference line (line above)
         // color is the current color (WHITE or BLACK)
         //
         byte[] refData = data;
         int lineAddr = 0;
         int outIndex = 0;

         initBitBuf();

         int KParameter = 2;
         for(int numRows = 0; numRows < height; numRows++) {
             if(is1DMode || (numRows % KParameter) == 0) { // 1D encoding
                 // Write EOL+1
                 outIndex += addEOL(is1DMode, isEOLAligned, true,
                                    compData, outIndex);

                 // Encode row
                 outIndex += encode1D(data, lineAddr, colOffset, width,
                                       compData, outIndex);
             } else { // 2D encoding.
                 // Write EOL+0
                 outIndex += addEOL(is1DMode, isEOLAligned, false,
                                    compData, outIndex);

                 // Set reference to previous line
                 int refAddr = lineAddr - lineStride;

                 // Encode row
                 int a0   = colOffset;
                 int last = a0 + width;

                 int testbit =
                     ((data[lineAddr + (a0>>>3)]&0xff) >>>
                      (7-(a0 & 0x7))) & 0x1;
                 int a1 = testbit != 0 ?
                     a0 : nextState(data, lineAddr, a0, last);

                 testbit = ((refData[refAddr + (a0>>>3)]&0xff) >>>
                            (7-(a0 & 0x7))) & 0x1;
                 int b1 = testbit != 0 ?
                     a0 : nextState(refData, refAddr, a0, last);

                 // The current color is set to WHITE at line start
                 int color = WHITE;

                 while(true) {
                     int b2 = nextState(refData, refAddr, b1, last);
                     if(b2 < a1) {          // pass mode
                         outIndex += add2DBits(compData, outIndex, pass, 0);
                         a0 = b2;
                     } else {
                         int tmp = b1 - a1 + 3;
                         if((tmp <= 6) && (tmp >= 0)) { // vertical mode
                             outIndex +=
                                 add2DBits(compData, outIndex, vert, tmp);
                             a0 = a1;
                         } else {            // horizontal mode
                             int a2 = nextState(data, lineAddr, a1, last);
                             outIndex +=
                                 add2DBits(compData, outIndex, horz, 0);
                             outIndex +=
                                 add1DBits(compData, outIndex, a1-a0, color);
                             outIndex +=
                                 add1DBits(compData, outIndex, a2-a1, color^1);
                             a0 = a2;
                         }
                     }
                     if(a0 >= last) {
                         break;
                     }
                     color = ((data[lineAddr + (a0>>>3)]&0xff) >>>
                              (7-(a0 & 0x7))) & 0x1;
                     a1 = nextState(data, lineAddr, a0, last);
                     b1 = nextState(refData, refAddr, a0, last);
                     testbit = ((refData[refAddr + (b1>>>3)]&0xff) >>>
                                (7-(b1 & 0x7))) & 0x1;
                     if(testbit == color) {
                         b1 = nextState(refData, refAddr, b1, last);
                     }
                 }
             }

             // Skip to next line.
             lineAddr += lineStride;
         }

         for(int i = 0; i < 6; i++) {
             outIndex += addEOL(is1DMode, isEOLAligned, true,
                                compData, outIndex);
         }

         //
         // flush all pending bits
         //
         while(ndex > 0) {
             compData[outIndex++] = (byte)(bits >>> 24);
             bits <<= 8;
             ndex -= 8;
         }

         // Flip the bytes if inverse fill was requested.
         if(inverseFill) {
             for(int i = 0; i < outIndex; i++) {
                 compData[i] = TIFFFaxDecompressor.flipTable[compData[i]&0xff];
             }
         }

         return outIndex;
     }

     public int encode(byte[] b, int off,
                       int width, int height,
                       int[] bitsPerSample,
                       int scanlineStride) throws IOException {
         if (bitsPerSample.length != 1 || bitsPerSample[0] != 1) {
             throw new IIOException(
                              "Bits per sample must be 1 for T4 compression!");
         }

         // This initial buffer size is based on an alternating 1-0
         // pattern generating the most bits when converted to code
         // words: 9 bits out for each pair of bits in. So the number
         // of bit pairs is determined, multiplied by 9, converted to
         // bytes, and a ceil() is taken to account for fill bits at the
         // end of each line.  The "2" addend accounts for the case
         // of the pattern beginning with black.  The buffer is intended
         // to hold only a single row.

         int maxBits = 9*((width + 1)/2) + 2;
         int bufSize = (maxBits + 7)/8;

         // Calculate the maximum row as the G3-1D size plus the EOL,
         // multiply this by the number of rows in the tile, and add
         // 6 EOLs for the RTC (return to control).
         bufSize = height*(bufSize + 2) + 12;

         byte[] compData = new byte[bufSize];

         int bytes = encodeT4(is1DMode,
                              isEOLAligned,
                              b, scanlineStride, 8*off,
                              width, height,
                              compData);

         stream.write(compData, 0, bytes);
         return bytes;
     }
 }
	/*
	* Copyright (c) 2005, 2016, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code is distributed in the hope that it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/
	package com.sun.imageio.plugins.tiff;

	import javax.imageio.plugins.tiff.BaselineTIFFTagSet;
	import javax.imageio.plugins.tiff.TIFFField;
	import javax.imageio.plugins.tiff.TIFFTag;
	import java.io.IOException;
	import javax.imageio.IIOException;
	import javax.imageio.metadata.IIOMetadata;

	public class TIFFT4Compressor extends TIFFFaxCompressor {

	private boolean is1DMode = false;
	private boolean isEOLAligned = false;

	public TIFFT4Compressor() {
	super("CCITT T.4", BaselineTIFFTagSet.COMPRESSION_CCITT_T_4, true);
	}

	/**
	* Sets the value of the {@code metadata} field.
	*
	* <p> The implementation in this class also sets local options
	* from the T4_OPTIONS field if it exists, and if it doesn't, adds
	* it with default values.</p>
	*
	* @param metadata the {@code IIOMetadata} object for the
	* image being written.
	*
	* @see #getMetadata()
	*/
	public void setMetadata(IIOMetadata metadata) {
	super.setMetadata(metadata);

	if (metadata instanceof TIFFImageMetadata) {
	TIFFImageMetadata tim = (TIFFImageMetadata)metadata;
	TIFFField f = tim.getTIFFField(BaselineTIFFTagSet.TAG_T4_OPTIONS);
	if (f != null) {
	int options = f.getAsInt(0);
	is1DMode = (options & 0x1) == 0;
	isEOLAligned = (options & 0x4) == 0x4;
	} else {
	long[] oarray = new long[1];
	oarray[0] = (isEOLAligned ? 0x4 : 0x0) \|
	(is1DMode ? 0x0 : 0x1);

	BaselineTIFFTagSet base = BaselineTIFFTagSet.getInstance();
	TIFFField T4Options =
	new TIFFField(base.getTag(BaselineTIFFTagSet.TAG_T4_OPTIONS),
	TIFFTag.TIFF_LONG,
	1,
	oarray);
	tim.rootIFD.addTIFFField(T4Options);
	}
	}
	}

	/**
	* Encode a buffer of data using CCITT T.4 Compression also known as
	* Group 3 facsimile compression.
	*
	* @param is1DMode Whether to perform one-dimensional encoding.
	* @param isEOLAligned Whether EOL bit sequences should be padded.
	* @param data The row of data to compress.
	* @param lineStride Byte step between the same sample in different rows.
	* @param colOffset Bit offset within first {@code data[rowOffset]}.
	* @param width Number of bits in the row.
	* @param height Number of rows in the buffer.
	* @param compData The compressed data.
	*
	* @return The number of bytes saved in the compressed data array.
	*/
	public int encodeT4(boolean is1DMode,
	boolean isEOLAligned,
	byte[] data,
	int lineStride,
	int colOffset,
	int width,
	int height,
	byte[] compData)
	{
	//
	// ao, a1, a2 are bit indices in the current line
	// b1 and b2 are bit indices in the reference line (line above)
	// color is the current color (WHITE or BLACK)
	//
	byte[] refData = data;
	int lineAddr = 0;
	int outIndex = 0;

	initBitBuf();

	int KParameter = 2;
	for(int numRows = 0; numRows < height; numRows++) {
	if(is1DMode \|\| (numRows % KParameter) == 0) { // 1D encoding
	// Write EOL+1
	outIndex += addEOL(is1DMode, isEOLAligned, true,
	compData, outIndex);

	// Encode row
	outIndex += encode1D(data, lineAddr, colOffset, width,
	compData, outIndex);
	} else { // 2D encoding.
	// Write EOL+0
	outIndex += addEOL(is1DMode, isEOLAligned, false,
	compData, outIndex);

	// Set reference to previous line
	int refAddr = lineAddr - lineStride;

	// Encode row
	int a0 = colOffset;
	int last = a0 + width;

	int testbit =
	((data[lineAddr + (a0>>>3)]&0xff) >>>
	(7-(a0 & 0x7))) & 0x1;
	int a1 = testbit != 0 ?
	a0 : nextState(data, lineAddr, a0, last);

	testbit = ((refData[refAddr + (a0>>>3)]&0xff) >>>
	(7-(a0 & 0x7))) & 0x1;
	int b1 = testbit != 0 ?
	a0 : nextState(refData, refAddr, a0, last);

	// The current color is set to WHITE at line start
	int color = WHITE;

	while(true) {
	int b2 = nextState(refData, refAddr, b1, last);
	if(b2 < a1) { // pass mode
	outIndex += add2DBits(compData, outIndex, pass, 0);
	a0 = b2;
	} else {
	int tmp = b1 - a1 + 3;
	if((tmp <= 6) && (tmp >= 0)) { // vertical mode
	outIndex +=
	add2DBits(compData, outIndex, vert, tmp);
	a0 = a1;
	} else { // horizontal mode
	int a2 = nextState(data, lineAddr, a1, last);
	outIndex +=
	add2DBits(compData, outIndex, horz, 0);
	outIndex +=
	add1DBits(compData, outIndex, a1-a0, color);
	outIndex +=
	add1DBits(compData, outIndex, a2-a1, color^1);
	a0 = a2;
	}
	}
	if(a0 >= last) {
	break;
	}
	color = ((data[lineAddr + (a0>>>3)]&0xff) >>>
	(7-(a0 & 0x7))) & 0x1;
	a1 = nextState(data, lineAddr, a0, last);
	b1 = nextState(refData, refAddr, a0, last);
	testbit = ((refData[refAddr + (b1>>>3)]&0xff) >>>
	(7-(b1 & 0x7))) & 0x1;
	if(testbit == color) {
	b1 = nextState(refData, refAddr, b1, last);
	}
	}
	}

	// Skip to next line.
	lineAddr += lineStride;
	}

	for(int i = 0; i < 6; i++) {
	outIndex += addEOL(is1DMode, isEOLAligned, true,
	compData, outIndex);
	}

	//
	// flush all pending bits
	//
	while(ndex > 0) {
	compData[outIndex++] = (byte)(bits >>> 24);
	bits <<= 8;
	ndex -= 8;
	}

	// Flip the bytes if inverse fill was requested.
	if(inverseFill) {
	for(int i = 0; i < outIndex; i++) {
	compData[i] = TIFFFaxDecompressor.flipTable[compData[i]&0xff];
	}
	}

	return outIndex;
	}

	public int encode(byte[] b, int off,
	int width, int height,
	int[] bitsPerSample,
	int scanlineStride) throws IOException {
	if (bitsPerSample.length != 1 \|\| bitsPerSample[0] != 1) {
	throw new IIOException(
	"Bits per sample must be 1 for T4 compression!");
	}

	// This initial buffer size is based on an alternating 1-0
	// pattern generating the most bits when converted to code
	// words: 9 bits out for each pair of bits in. So the number
	// of bit pairs is determined, multiplied by 9, converted to
	// bytes, and a ceil() is taken to account for fill bits at the
	// end of each line. The "2" addend accounts for the case
	// of the pattern beginning with black. The buffer is intended
	// to hold only a single row.

	int maxBits = 9*((width + 1)/2) + 2;
	int bufSize = (maxBits + 7)/8;

	// Calculate the maximum row as the G3-1D size plus the EOL,
	// multiply this by the number of rows in the tile, and add
	// 6 EOLs for the RTC (return to control).
	bufSize = height*(bufSize + 2) + 12;

	byte[] compData = new byte[bufSize];

	int bytes = encodeT4(is1DMode,
	isEOLAligned,
	b, scanlineStride, 8*off,
	width, height,
	compData);

	stream.write(compData, 0, bytes);
	return bytes;
	}
	}