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diff --git a/src/gifenc.cpp b/src/gifenc.cpp
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+/******************************************************************************
+ *
+ * $Id$
+ *
+ *
+ * Copyright (C) 1997-2009 by Dimitri van Heesch.
+ *
+ * Permission to use, copy, modify, and distribute this software and its
+ * documentation under the terms of the GNU General Public License is hereby 
+ * granted. No representations are made about the suitability of this software 
+ * for any purpose. It is provided "as is" without express or implied warranty.
+ * See the GNU General Public License for more details.
+ *
+ * All output generated with Doxygen is not covered by this license.
+ *
+ * The GIF compression code below is based on the file ppmtogif.c of the
+ * netpbm package. The original copyright message follows:
+ *
+ * ---------------------------------------------------------------------------
+ * 
+ * Copyright (C) 1989 by Jef Poskanzer.
+ *
+ * Permission to use, copy, modify, and distribute this software and its
+ * documentation for any purpose and without fee is hereby granted, provided
+ * that the above copyright notice appear in all copies and that both that
+ * copyright notice and this permission notice appear in supporting
+ * documentation.  This software is provided "as is" without express or
+ * implied warranty.
+ *
+ * ---------------------------------------------------------------------------
+ *
+ * The Graphics Interchange Format(c) is the Copyright property of
+ * CompuServe Incorporated.  GIF(sm) is a Service Mark property of
+ * CompuServe Incorporated.
+ */
+
+#include "gifenc.h"
+
+static const unsigned int masks[] = { 0x0000, 0x0001, 0x0003, 0x0007, 0x000F,
+                                      0x001F, 0x003F, 0x007F, 0x00FF,
+                                      0x01FF, 0x03FF, 0x07FF, 0x0FFF,
+                                      0x1FFF, 0x3FFF, 0x7FFF, 0xFFFF };
+
+GifEncoder::GifEncoder(Byte *rawBytes,Color *p,int w,int h, Byte d,
+                       int t)
+  : colorResolution(8),globalPaletteFlag(0x80),bits(12),
+    maxMaxCode(1<<bits)
+{
+  width = w;
+  height = h;
+  depth = d;
+  transIndex = t;
+  palette = p;
+  data = rawBytes;
+  dataPtr = data;
+}
+
+GifEncoder::~GifEncoder()
+{
+}
+
+void GifEncoder::writeGIF(QFile &fp)
+{
+  // Write the Magic header
+  fp.writeBlock( transIndex < 0 ? "GIF87a" : "GIF89a", 6 );
+
+  // Write the logical screen descriptor
+  putWord( width,   fp );
+  putWord( height,  fp );
+  Byte pack = globalPaletteFlag | ((colorResolution-1)<<4) | (depth-1);
+  putByte( pack,    fp );
+  putByte( 0,       fp ); // the background color
+  putByte( 0,       fp ); // no aspect ration defined
+
+  // Write global color table
+  int i; for ( i=0 ; i< (1<<depth) ; i++)
+  {
+    putByte(palette[i].red,  fp);
+    putByte(palette[i].green,fp);
+    putByte(palette[i].blue, fp);
+  }
+  
+  if ( transIndex >= 0)
+  {
+    // Write graphic control extension (needed for GIF transparancy)
+    putByte( 0x21, fp); // extension introducer
+    putByte( 0xf9, fp); // graphic control label
+    putByte(    4, fp); // block size
+    putByte(    1, fp); // announce transparacy value
+    putWord(    0, fp); // zero delay time
+    putByte( transIndex, fp); // write transparant index
+    putByte(    0, fp); // end block
+  }
+  
+  // Write the image descriptor
+  putByte(   0x2c, fp); // image separator
+  putWord(      0, fp); // image left position
+  putWord(      0, fp); // image top position
+  putWord(  width, fp); // image width
+  putWord( height, fp); // image height
+  putByte(      0, fp); // no local color table, no interlacing
+ 
+  // Write table based image data
+  Byte initCodeSize = depth<=1 ? 2 : depth;
+  putByte( initCodeSize, fp); // LZW Minimum Code Size
+  compress( initCodeSize+1, fp);
+  putByte( 0, fp); // end of blocks
+ 
+  // Write GIF Trailer
+  putByte( 0x3b, fp);
+}
+
+void GifEncoder::compress( int ibits, QFile &outfile )
+{
+  int i;
+  int entry;
+
+  initBits  = ibits;
+  numPixels = width*height;
+  dataPtr   = data;
+  clearFlag = FALSE;
+  nBits     = initBits;
+  maxCode   = (1<<nBits) -1;
+  ClearCode = (1 << (initBits - 1));
+  EOFCode   = ClearCode + 1;
+  freeEntry = ClearCode + 2;
+  aCount    = 0;
+  curAccum  = 0;
+  curBits   = 0;
+
+  entry = nextPixel();
+
+  int hshift = 0;
+  int fcode;
+  for ( fcode = hashTableSize;  fcode < 65536L; fcode *= 2L ) ++hshift;
+  hshift = 8 - hshift;                /* set hash code range bound */
+
+  clearHashTable();                   /* clear hash table */
+
+  writeCode( ClearCode,outfile );
+
+  int c;
+  while ( (c = nextPixel()) != EOF ) 
+  {  
+    fcode = (c << bits) + entry;
+    i = (c << hshift) ^ entry;    /* xor hashing */
+
+    bool found=FALSE;
+    if (htab[i]==fcode) 
+    {
+      entry = codetab[i];
+      found=TRUE;
+    } 
+    else if (htab[i]>=0)
+    {
+      int disp = hashTableSize - i;
+      if (i==0) disp=1;
+      do
+      {
+        if ((i-=disp)<0) i+=hashTableSize;
+        if (htab[i]==fcode)
+        {
+          entry=codetab[i];
+          found=TRUE;
+        }
+      } while (htab[i]>0 && !found);
+    }
+    if (!found)
+    {
+      writeCode( entry, outfile );
+      entry = c;
+      if ( freeEntry < maxMaxCode ) 
+      {
+        codetab[i] = freeEntry++; /* code -> hashtable */
+        htab[i]    = fcode;
+      } 
+      else
+      {
+        clearHashTable();
+        freeEntry = ClearCode + 2;
+        clearFlag = TRUE;
+        writeCode( ClearCode, outfile );
+      }
+    }
+  }
+  writeCode( entry, outfile );
+  writeCode( EOFCode, outfile );
+}
+
+void GifEncoder::putWord( Word w, QFile &fp )
+{
+  fp.putch( w & 0xff );
+  fp.putch( (w>>8) & 0xff );
+}
+
+void GifEncoder::putByte( Byte b, QFile &fp )
+{
+  fp.putch( b );
+}
+
+void GifEncoder::writeCode( int code, QFile &outfile )
+{
+  curAccum &= masks[ curBits ];
+
+  if ( curBits > 0 ) 
+  {
+    curAccum |= (code << curBits);
+  }
+  else
+  {
+    curAccum = code;
+  }
+
+  curBits += nBits;
+
+  while( curBits >= 8 ) 
+  {
+    writeChar( (Byte)(curAccum & 0xff),outfile );
+    curAccum >>= 8;
+    curBits -= 8;
+  }
+
+  /*
+   * If the next entry is going to be too big for the code size,
+   * then increase it, if possible.
+   */
+  if ( freeEntry > maxCode || clearFlag ) 
+  {
+    if( clearFlag ) 
+    {
+      nBits = initBits;
+      maxCode = (1<<nBits)-1;
+      clearFlag = FALSE;
+    } 
+    else 
+    {
+      ++nBits;
+      if ( nBits == bits )
+        maxCode = maxMaxCode;
+      else
+        maxCode = (1<<nBits)-1;
+    }
+  }
+
+  if ( code == EOFCode ) 
+  {
+    /* At EOF, write the rest of the buffer.  */
+    while( curBits > 0 ) 
+    {
+      writeChar( (Byte)(curAccum & 0xff), outfile );
+      curAccum >>= 8;
+      curBits -= 8;
+    }
+
+    writePacket(outfile);
+  }
+}
+
+/*
+ * Add a character to the end of the current packet, and if it is 254
+ * characters, flush the packet to disk.
+ */
+void GifEncoder::writeChar( Byte c, QFile &fp )
+{
+  accum[ aCount++ ] = c;
+  if( aCount >= 254 ) writePacket(fp);
+}
+
+/*
+ * Flush the packet to disk, and reset the accumulator
+ */
+void GifEncoder::writePacket(QFile &fp)
+{
+  if ( aCount > 0 ) 
+  {
+    fp.putch( aCount );
+    fp.writeBlock( (const char *)accum, aCount );
+    aCount = 0;
+  }
+}
+
+void GifEncoder::clearHashTable()          /* reset code table */
+{
+  int *htab_p = htab;
+  int i; for (i=0;i<hashTableSize;i++) *htab_p++ = -1;
+}
+