/*
* #%L
* Fork of JAI Image I/O Tools.
* %%
* Copyright (C) 2008 - 2014 Open Microscopy Environment:
* - Board of Regents of the University of Wisconsin-Madison
* - Glencoe Software, Inc.
* - University of Dundee
* %%
* 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 COPYRIGHT HOLDERS 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 COPYRIGHT HOLDERS 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.
*
* The views and conclusions contained in the software and documentation are
* those of the authors and should not be interpreted as representing official
* policies, either expressed or implied, of any organization.
* #L%
*/
/*
* $RCSfile: BitFile.java,v $
*
*
* Copyright (c) 2005 Sun Microsystems, Inc. All Rights Reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistribution of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* - Redistribution 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.
*
* Neither the name of Sun Microsystems, Inc. or the names of
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* This software is provided "AS IS," without a warranty of any
* kind. ALL EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND
* WARRANTIES, INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT, ARE HEREBY
* EXCLUDED. SUN MIDROSYSTEMS, INC. ("SUN") AND ITS LICENSORS SHALL
* NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF
* USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS
* DERIVATIVES. IN NO EVENT WILL SUN OR ITS LICENSORS BE LIABLE FOR
* ANY LOST REVENUE, PROFIT OR DATA, OR FOR DIRECT, INDIRECT, SPECIAL,
* CONSEQUENTIAL, INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER CAUSED AND
* REGARDLESS OF THE THEORY OF LIABILITY, ARISING OUT OF THE USE OF OR
* INABILITY TO USE THIS SOFTWARE, EVEN IF SUN HAS BEEN ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGES.
*
* You acknowledge that this software is not designed or intended for
* use in the design, construction, operation or maintenance of any
* nuclear facility.
*
* $Revision: 1.1 $
* $Date: 2005/02/11 05:01:21 $
* $State: Exp $
*/
package com.sun.media.imageioimpl.common;
import java.io.IOException;
import javax.imageio.stream.ImageOutputStream;
/**
* Came from GIFEncoder initially.
* Modified - to allow for output compressed data without the block counts
* which breakup the compressed data stream for GIF.
**/
public class BitFile
{
ImageOutputStream output_;
byte buffer_[];
int index_;
int bitsLeft_; // bits left at current index that are avail.
/** note this also indicates gif format BITFile. **/
boolean blocks_ = false;
/**
* @param output destination for output data
* @param blocks GIF LZW requires block counts for output data
**/
public BitFile(ImageOutputStream output, boolean blocks)
{
output_ = output;
blocks_ = blocks;
buffer_ = new byte[256];
index_ = 0;
bitsLeft_ = 8;
}
public void flush() throws IOException
{
int numBytes = index_ + (bitsLeft_ == 8 ? 0 : 1);
if (numBytes > 0)
{
if (blocks_)
output_.write(numBytes);
output_.write(buffer_, 0, numBytes);
buffer_[0] = 0;
index_ = 0;
bitsLeft_ = 8;
}
}
public void writeBits(int bits, int numbits) throws IOException
{
int bitsWritten = 0;
int numBytes = 255; // gif block count
do
{
// This handles the GIF block count stuff
if ((index_ == 254 && bitsLeft_ == 0) || index_ > 254)
{
if (blocks_)
output_.write(numBytes);
output_.write(buffer_, 0, numBytes);
buffer_[0] = 0;
index_ = 0;
bitsLeft_ = 8;
}
if (numbits <= bitsLeft_) // bits contents fit in current index byte
{
if (blocks_) // GIF
{
buffer_[index_] |= (bits & ((1 << numbits) - 1)) << (8 - bitsLeft_);
bitsWritten += numbits;
bitsLeft_ -= numbits;
numbits = 0;
}
else
{
buffer_[index_] |= (bits & ((1 << numbits) - 1)) << (bitsLeft_ - numbits);
bitsWritten += numbits;
bitsLeft_ -= numbits;
numbits = 0;
}
}
else // bits overflow from current byte to next.
{
if (blocks_) // GIF
{
// if bits > space left in current byte then the lowest order bits
// of code are taken and put in current byte and rest put in next.
buffer_[index_] |= (bits & ((1 << bitsLeft_) - 1)) << (8 - bitsLeft_);
bitsWritten += bitsLeft_;
bits >>= bitsLeft_;
numbits -= bitsLeft_;
buffer_[++index_] = 0;
bitsLeft_ = 8;
}
else
{
// if bits > space left in current byte then the highest order bits
// of code are taken and put in current byte and rest put in next.
// at highest order bit location !!
int topbits = (bits >>> (numbits - bitsLeft_)) & ((1 << bitsLeft_) - 1);
buffer_[index_] |= topbits;
numbits -= bitsLeft_; // ok this many bits gone off the top
bitsWritten += bitsLeft_;
buffer_[++index_] = 0; // next index
bitsLeft_ = 8;
}
}
} while (numbits != 0);
}
}