539 lines
15 KiB
C++
539 lines
15 KiB
C++
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// Copyright (C) 2000 Tridia Corporation. All Rights Reserved.
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// Copyright (C) 1999 AT&T Laboratories Cambridge. All Rights Reserved.
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//
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// This file is part of the VNC system.
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//
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// The VNC system is free software; you can redistribute it and/or modify
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// it under the terms of the GNU General Public License as published by
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// the Free Software Foundation; either version 2 of the License, or
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// (at your option) any later version.
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//
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// This program is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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// GNU General Public License for more details.
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//
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// You should have received a copy of the GNU General Public License
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// along with this program; if not, write to the Free Software
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// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
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// USA.
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//
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// TightVNC distribution homepage on the Web: http://www.tightvnc.com/
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//
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// If the source code for the VNC system is not available from the place
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// whence you received this file, check http://www.uk.research.att.com/vnc or contact
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// the authors on vnc@uk.research.att.com for information on obtaining it.
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// vncEncodeCoRRE
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// This file implements the vncEncoder-derived vncEncodeCoRRE class.
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// This class overrides some vncEncoder functions to produce a
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// Compact RRE encoder. Compact RRE (CoRRE) uses fewer bytes to
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// encode each subrect, which makes it faster in general. It also
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// splits large rectangles up into ones of at most 256 pixels width
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// & height. This results in better granularity to use for deciding
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// whether to send RAW or CoRRE/RRE.
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#include "vncEncodeCoRRE.h"
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#include "rfb.h"
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#include "MinMax.h"
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#include <stdlib.h>
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#include <time.h>
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vncEncodeCoRRE::vncEncodeCoRRE()
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{
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m_buffer = NULL;
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m_bufflen = 0;
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// Set some sensible defaults
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m_maxwidth = 24;
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m_maxheight = 24;
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m_maxadjust = 1;
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// Set the threshold up/down probability
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m_threshold = 50;
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// Seed the random number generator
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srand((unsigned)time(NULL));
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m_statsready = FALSE;
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m_encodedbytes = 0;
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m_rectbytes = 0;
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}
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vncEncodeCoRRE::~vncEncodeCoRRE()
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{
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if (m_buffer != NULL)
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{
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delete [] m_buffer;
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m_buffer = NULL;
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}
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}
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void vncEncodeCoRRE::Init()
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{
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vncEncoder::Init();
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}
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UINT vncEncodeCoRRE::RequiredBuffSize(UINT width, UINT height)
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{
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RECT fullscreen;
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UINT codedrects;
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// Work out how many rectangles the entire screen would
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// be re-encoded to...
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fullscreen.left = 0;
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fullscreen.top = 0;
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fullscreen.right = width;
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fullscreen.bottom = height;
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codedrects = NumCodedRects(fullscreen);
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// The buffer size required is the size of raw data for the whole
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// screen plus enough space for the required number of rectangle
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// headers.
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// This is inherently always greater than the RAW encoded size of
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// the whole screen!
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return (codedrects * sz_rfbFramebufferUpdateRectHeader) +
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(width * height * m_remoteformat.bitsPerPixel)/8;
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}
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UINT
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vncEncodeCoRRE::NumCodedRects(RECT &rect)
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{
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// If we have any statistical data handy then adjust the CoRRE sizes
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if (m_statsready)
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{
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m_statsready = FALSE;
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UINT newscore = m_encodedbytes * m_lastrectbytes;
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UINT oldscore = m_lastencodedbytes * m_rectbytes;
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if (newscore <= oldscore)
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{
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// The change was a good one, so adjust the threshold accordingly!
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m_threshold = Max(5, Min(95, m_threshold + m_maxadjust));
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m_maxwidth = Max(8, Min(255, m_maxwidth + m_maxadjust));
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m_maxheight = Max(8, Min(255, m_maxheight + m_maxadjust));
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}
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else
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{
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// The change was a bad one, so adjust the threshold accordingly!
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// m_threshold = Max(5, Min(95, m_threshold - m_maxadjust));
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}
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// Now calculate a new adjustment and apply it
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m_maxadjust = ((rand() % 99)<m_threshold) ? 1 : -1;
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// Prepare the stats data for next time...
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m_lastencodedbytes = m_encodedbytes;
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m_lastrectbytes = m_rectbytes;
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m_encodedbytes = 0;
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m_rectbytes = 0;
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}
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// Now return the number of rects that this one would encode to
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if ((rect.bottom-rect.top) > m_maxheight)
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{
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RECT subrect1, subrect2;
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// Find how many rects the two subrects would take
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subrect1.left = rect.left;
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subrect1.right = rect.right;
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subrect1.top = rect.top;
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subrect1.bottom = rect.top + m_maxheight;
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subrect2.left = rect.left;
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subrect2.right = rect.right;
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subrect2.top = rect.top + m_maxheight;
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subrect2.bottom = rect.bottom;
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return NumCodedRects(subrect1) + NumCodedRects(subrect2);
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}
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if ((rect.right-rect.left) > m_maxwidth)
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{
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RECT subrect1, subrect2;
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// Find how many rects the two subrects would take
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subrect1.left = rect.left;
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subrect1.right = rect.left + m_maxwidth;
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subrect1.top = rect.top;
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subrect1.bottom = rect.bottom;
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subrect2.left = rect.left + m_maxwidth;
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subrect2.right = rect.right;
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subrect2.top = rect.top;
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subrect2.bottom = rect.bottom;
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return NumCodedRects(subrect1) + NumCodedRects(subrect2);
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}
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// This rectangle is small enough not to require splitting
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return 1;
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}
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/*
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* corre.c
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*
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* Routines to implement Compact Rise-and-Run-length Encoding (CoRRE). This
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* code is based on krw's original javatel rfbserver.
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*/
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/*
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* This version modified for WinVNC by jnw.
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*/
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static int rreAfterBufLen;
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static int subrectEncode8 (CARD8 *source, CARD8 *dest, int w, int h, int max);
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static int subrectEncode16 (CARD16 *source, CARD8 *dest, int w, int h, int max);
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static int subrectEncode32 (CARD32 *source, CARD8 *dest, int w, int h, int max);
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static CARD32 getBgColour (char *data, int size, int bpp);
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/*
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* vncEncodeCoRRE::EncodeRect - send an arbitrary size rectangle using CoRRE
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* encoding.
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*/
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UINT
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vncEncodeCoRRE::EncodeRect(BYTE *source, BYTE *dest, const RECT &rect, int offx, int offy)
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{
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// Do the encoding
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UINT size = InternalEncodeRect(source, dest, rect);
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const int rectW = rect.right - rect.left;
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const int rectH = rect.bottom - rect.top;
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offsetx = offx;
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offsety = offy;
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// Will this rectangle have been split for encoding?
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if ((rectW>m_maxwidth) || (rectH>m_maxheight))
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{
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// Yes : Once we return, the stats will be valid!
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m_statsready = TRUE;
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// Update the stats
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m_encodedbytes += size;
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m_rectbytes += sz_rfbFramebufferUpdateRectHeader +
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(rectW*rectH*m_remoteformat.bitsPerPixel/8);
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}
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return size;
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}
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UINT
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vncEncodeCoRRE::InternalEncodeRect(BYTE *source, BYTE *dest, const RECT &rect)
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{
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int size = 0;
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if ((rect.bottom-rect.top) > m_maxheight)
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{
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RECT subrect;
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// Rectangle is too high - split it into two subrects to send
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subrect.left = rect.left;
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subrect.right = rect.right;
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subrect.top = rect.top;
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subrect.bottom = rect.top + m_maxheight;
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size += InternalEncodeRect(source, dest + size, subrect);
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subrect.left = rect.left;
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subrect.right = rect.right;
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subrect.top = rect.top + m_maxheight;
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subrect.bottom = rect.bottom;
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size += InternalEncodeRect(source, dest + size, subrect);
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return size;
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}
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if ((rect.right-rect.left) > m_maxwidth)
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{
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RECT subrect;
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// Rectangle is too high - split it into two subrects to send
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subrect.left = rect.left;
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subrect.right = rect.left + m_maxwidth;
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subrect.top = rect.top;
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subrect.bottom = rect.bottom;
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size += InternalEncodeRect(source, dest + size, subrect);
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subrect.left = rect.left + m_maxwidth;
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subrect.right = rect.right;
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subrect.top = rect.top;
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subrect.bottom = rect.bottom;
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size += InternalEncodeRect(source, dest + size, subrect);
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return size;
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}
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return EncodeSmallRect(source, dest, rect);
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}
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void
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vncEncodeCoRRE::SetCoRREMax(BYTE width, BYTE height)
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{
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m_maxwidth = width;
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m_maxheight = height;
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}
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/*
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* EncodeSmallRect - send a small (guaranteed < 256x256)
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* rectangle using CoRRE encoding.
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*/
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UINT
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vncEncodeCoRRE::EncodeSmallRect(BYTE *source, BYTE *dest, const RECT &rect)
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{
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int subrects = -1;
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const UINT rectW = rect.right - rect.left;
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const UINT rectH = rect.bottom - rect.top;
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// Create the rectangle header
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rfbFramebufferUpdateRectHeader *surh=(rfbFramebufferUpdateRectHeader *)dest;
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surh->r.x = (CARD16) rect.left;
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surh->r.y = (CARD16) rect.top;
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surh->r.w = (CARD16) (rectW);
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surh->r.h = (CARD16) (rectH);
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surh->r.x = Swap16IfLE(surh->r.x - offsetx);
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surh->r.y = Swap16IfLE(surh->r.y - offsety);
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surh->r.w = Swap16IfLE(surh->r.w);
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surh->r.h = Swap16IfLE(surh->r.h);
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surh->encoding = Swap32IfLE(rfbEncodingCoRRE);
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// create a space big enough for the CoRRE encoded pixels
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size_t rectSize = rectW * rectH * (m_remoteformat.bitsPerPixel / 8);
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if (m_bufflen < rectSize)
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{
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if (m_buffer != NULL)
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{
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delete [] m_buffer;
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m_buffer = NULL;
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}
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m_buffer = new BYTE [rectSize + 1];
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if (m_buffer == NULL)
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return vncEncoder::EncodeRect(source, dest, rect, offsetx, offsety);
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m_bufflen = rectSize;
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}
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// Translate the data into our new buffer
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Translate(source, m_buffer, rect);
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// The Buffer object will have ensured that the destination buffer is
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// big enough using RequiredBuffSize
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// Choose the appropriate encoding routine (for speed...)
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switch(m_remoteformat.bitsPerPixel)
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{
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case 8:
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subrects = subrectEncode8(
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m_buffer,
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dest+sz_rfbFramebufferUpdateRectHeader+sz_rfbRREHeader,
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rectW,
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rectH,
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(int)(m_bufflen-sz_rfbFramebufferUpdateRectHeader-sz_rfbRREHeader)
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);
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break;
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case 16:
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subrects = subrectEncode16(
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(CARD16 *)m_buffer,
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(CARD8 *)(dest+sz_rfbFramebufferUpdateRectHeader+sz_rfbRREHeader),
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rectW,
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rectH,
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(int)(m_bufflen-sz_rfbFramebufferUpdateRectHeader-sz_rfbRREHeader)
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);
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break;
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case 32:
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subrects = subrectEncode32(
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(CARD32 *)m_buffer,
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(CARD8 *)(dest+sz_rfbFramebufferUpdateRectHeader+sz_rfbRREHeader),
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rectW,
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rectH,
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(int)(m_bufflen-sz_rfbFramebufferUpdateRectHeader-sz_rfbRREHeader)
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);
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break;
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}
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// If we couldn't encode the rectangles then just send the data raw
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if (subrects < 0)
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return vncEncoder::EncodeRect(source, dest, rect, offsetx, offsety);
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// Send the RREHeader
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rfbRREHeader *rreh=(rfbRREHeader *)(dest+sz_rfbFramebufferUpdateRectHeader);
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rreh->nSubrects = Swap32IfLE(subrects);
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// Update the statistics for this rectangle.
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encodedSize += sz_rfbRREHeader + rreAfterBufLen;
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rectangleOverhead += sz_rfbFramebufferUpdateRectHeader;
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dataSize += ( rectW * rectH * m_remoteformat.bitsPerPixel) / 8;
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transmittedSize += sz_rfbFramebufferUpdateRectHeader + sz_rfbRREHeader + rreAfterBufLen;
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// Calculate the size of the buffer produced
|
||
|
|
return sz_rfbFramebufferUpdateRectHeader + sz_rfbRREHeader + rreAfterBufLen;
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
* subrectEncode() encodes the given multicoloured rectangle as a background
|
||
|
|
* colour overwritten by single-coloured rectangles. It returns the number
|
||
|
|
* of subrectangles in the encoded buffer, or -1 if subrect encoding won't
|
||
|
|
* fit in the buffer. It puts the encoded rectangles in rreAfterBuf. The
|
||
|
|
* single-colour rectangle partition is not optimal, but does find the biggest
|
||
|
|
* horizontal or vertical rectangle top-left anchored to each consecutive
|
||
|
|
* coordinate position.
|
||
|
|
*
|
||
|
|
* The coding scheme is simply [<bgcolour><subrect><subrect>...] where each
|
||
|
|
* <subrect> is [<colour><x><y><w><h>].
|
||
|
|
*/
|
||
|
|
|
||
|
|
#define DEFINE_SUBRECT_ENCODE(bpp) \
|
||
|
|
static int \
|
||
|
|
subrectEncode##bpp( \
|
||
|
|
CARD##bpp *source, \
|
||
|
|
CARD8 *dest, \
|
||
|
|
int w, \
|
||
|
|
int h, \
|
||
|
|
int maxbytes) \
|
||
|
|
{ \
|
||
|
|
CARD##bpp cl; \
|
||
|
|
rfbCoRRERectangle subrect; \
|
||
|
|
int x,y; \
|
||
|
|
int i,j; \
|
||
|
|
int hx=0,hy,vx=0,vy; \
|
||
|
|
int hyflag; \
|
||
|
|
CARD##bpp *seg; \
|
||
|
|
CARD##bpp *line; \
|
||
|
|
int hw,hh,vw,vh; \
|
||
|
|
int thex,they,thew,theh; \
|
||
|
|
int numsubs = 0; \
|
||
|
|
int newLen; \
|
||
|
|
CARD##bpp bg = (CARD##bpp)getBgColour((char*)source,w*h,bpp); \
|
||
|
|
\
|
||
|
|
*((CARD##bpp*)dest) = bg; \
|
||
|
|
\
|
||
|
|
rreAfterBufLen = (bpp/8); \
|
||
|
|
\
|
||
|
|
for (y=0; y<h; y++) { \
|
||
|
|
line = source+(y*w); \
|
||
|
|
for (x=0; x<w; x++) { \
|
||
|
|
if (line[x] != bg) { \
|
||
|
|
cl = line[x]; \
|
||
|
|
hy = y-1; \
|
||
|
|
hyflag = 1; \
|
||
|
|
for (j=y; j<h; j++) { \
|
||
|
|
seg = source+(j*w); \
|
||
|
|
if (seg[x] != cl) {break;} \
|
||
|
|
i = x; \
|
||
|
|
while ((seg[i] == cl) && (i < w)) i += 1; \
|
||
|
|
i -= 1; \
|
||
|
|
if (j == y) vx = hx = i; \
|
||
|
|
if (i < vx) vx = i; \
|
||
|
|
if ((hyflag > 0) && (i >= hx)) {hy += 1;} else {hyflag = 0;} \
|
||
|
|
} \
|
||
|
|
vy = j-1; \
|
||
|
|
\
|
||
|
|
/* We now have two possible subrects: (x,y,hx,hy) and (x,y,vx,vy) \
|
||
|
|
* We'll choose the bigger of the two. \
|
||
|
|
*/ \
|
||
|
|
hw = hx-x+1; \
|
||
|
|
hh = hy-y+1; \
|
||
|
|
vw = vx-x+1; \
|
||
|
|
vh = vy-y+1; \
|
||
|
|
\
|
||
|
|
thex = x; \
|
||
|
|
they = y; \
|
||
|
|
\
|
||
|
|
if ((hw*hh) > (vw*vh)) { \
|
||
|
|
thew = hw; \
|
||
|
|
theh = hh; \
|
||
|
|
} else { \
|
||
|
|
thew = vw; \
|
||
|
|
theh = vh; \
|
||
|
|
} \
|
||
|
|
\
|
||
|
|
subrect.x = thex; \
|
||
|
|
subrect.y = they; \
|
||
|
|
subrect.w = thew; \
|
||
|
|
subrect.h = theh; \
|
||
|
|
\
|
||
|
|
newLen = rreAfterBufLen + (bpp/8) + sz_rfbCoRRERectangle; \
|
||
|
|
if ((newLen > (w * h * (bpp/8))) || (newLen > maxbytes)) \
|
||
|
|
return -1; \
|
||
|
|
\
|
||
|
|
numsubs += 1; \
|
||
|
|
*((CARD##bpp*)(dest + rreAfterBufLen)) = cl; \
|
||
|
|
rreAfterBufLen += (bpp/8); \
|
||
|
|
memcpy(&dest[rreAfterBufLen],&subrect,sz_rfbCoRRERectangle); \
|
||
|
|
rreAfterBufLen += sz_rfbCoRRERectangle; \
|
||
|
|
\
|
||
|
|
/* \
|
||
|
|
* Now mark the subrect as done. \
|
||
|
|
*/ \
|
||
|
|
for (j=they; j < (they+theh); j++) { \
|
||
|
|
for (i=thex; i < (thex+thew); i++) { \
|
||
|
|
source[j*w+i] = bg; \
|
||
|
|
} \
|
||
|
|
} \
|
||
|
|
} \
|
||
|
|
} \
|
||
|
|
} \
|
||
|
|
\
|
||
|
|
return numsubs; \
|
||
|
|
}
|
||
|
|
|
||
|
|
DEFINE_SUBRECT_ENCODE(8)
|
||
|
|
DEFINE_SUBRECT_ENCODE(16)
|
||
|
|
DEFINE_SUBRECT_ENCODE(32)
|
||
|
|
|
||
|
|
/*
|
||
|
|
* getBgColour() gets the most prevalent colour in a byte array.
|
||
|
|
*/
|
||
|
|
static CARD32
|
||
|
|
getBgColour(
|
||
|
|
char *data,
|
||
|
|
int size,
|
||
|
|
int bpp)
|
||
|
|
{
|
||
|
|
|
||
|
|
#define NUMCLRS 256
|
||
|
|
|
||
|
|
static int counts[NUMCLRS];
|
||
|
|
int i,j,k;
|
||
|
|
|
||
|
|
int maxcount = 0;
|
||
|
|
CARD8 maxclr = 0;
|
||
|
|
|
||
|
|
if (bpp != 8) {
|
||
|
|
if (bpp == 16) {
|
||
|
|
return ((CARD16 *)data)[0];
|
||
|
|
} else if (bpp == 32) {
|
||
|
|
return ((CARD32 *)data)[0];
|
||
|
|
} else {
|
||
|
|
fprintf(stderr,"getBgColour: bpp %d?\n",bpp);
|
||
|
|
exit(1);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
for (i=0; i<NUMCLRS; i++) {
|
||
|
|
counts[i] = 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
for (j=0; j<size; j++) {
|
||
|
|
k = (int)(((CARD8 *)data)[j]);
|
||
|
|
if (k >= NUMCLRS) {
|
||
|
|
fprintf(stderr, "%s: unusual colour = %d\n", "getBgColour",k);
|
||
|
|
exit(1);
|
||
|
|
}
|
||
|
|
counts[k] += 1;
|
||
|
|
if (counts[k] > maxcount) {
|
||
|
|
maxcount = counts[k];
|
||
|
|
maxclr = ((CARD8 *)data)[j];
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
return maxclr;
|
||
|
|
}
|