| 1 |
/* |
| 2 |
rdesktop: A Remote Desktop Protocol client. |
| 3 |
Bitmap decompression routines |
| 4 |
Copyright (C) Matthew Chapman 1999-2000 |
| 5 |
|
| 6 |
This program is free software; you can redistribute it and/or modify |
| 7 |
it under the terms of the GNU General Public License as published by |
| 8 |
the Free Software Foundation; either version 2 of the License, or |
| 9 |
(at your option) any later version. |
| 10 |
|
| 11 |
This program is distributed in the hope that it will be useful, |
| 12 |
but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 |
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 |
GNU General Public License for more details. |
| 15 |
|
| 16 |
You should have received a copy of the GNU General Public License |
| 17 |
along with this program; if not, write to the Free Software |
| 18 |
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
| 19 |
*/ |
| 20 |
|
| 21 |
#include "rdesktop.h" |
| 22 |
|
| 23 |
#define CVAL(p) (*(p++)) |
| 24 |
#define SVAL(p) ((*((p++) + 1) << 8) | CVAL(p)) |
| 25 |
|
| 26 |
#define REPEAT(statement) { while ((count > 0) && (x < width)) { statement; count--; x++; } } |
| 27 |
#define MASK_UPDATE() { mixmask <<= 1; if (mixmask == 0) { mask = CVAL(input); mixmask = 1; } } |
| 28 |
|
| 29 |
BOOL bitmap_decompress(unsigned char *output, int width, int height, |
| 30 |
unsigned char *input, int size) |
| 31 |
{ |
| 32 |
unsigned char *end = input + size; |
| 33 |
unsigned char *prevline = NULL, *line = NULL; |
| 34 |
int opcode, count, offset, isfillormix, x = width; |
| 35 |
int lastopcode = -1, insertmix = False; |
| 36 |
uint8 code, colour1 = 0, colour2 = 0; |
| 37 |
uint8 mixmask, mask = 0, mix = 0xff; |
| 38 |
|
| 39 |
while (input < end) |
| 40 |
{ |
| 41 |
code = CVAL(input); |
| 42 |
opcode = code >> 4; |
| 43 |
|
| 44 |
/* Handle different opcode forms */ |
| 45 |
switch (opcode) |
| 46 |
{ |
| 47 |
case 0xc: |
| 48 |
case 0xd: |
| 49 |
case 0xe: |
| 50 |
opcode -= 6; |
| 51 |
count = code & 0xf; |
| 52 |
offset = 16; |
| 53 |
break; |
| 54 |
|
| 55 |
case 0xf: |
| 56 |
opcode = code & 0xf; |
| 57 |
count = (opcode < 13) ? SVAL(input) : 1; |
| 58 |
offset = 0; |
| 59 |
break; |
| 60 |
|
| 61 |
default: |
| 62 |
opcode >>= 1; |
| 63 |
count = code & 0x1f; |
| 64 |
offset = 32; |
| 65 |
break; |
| 66 |
} |
| 67 |
|
| 68 |
/* Handle strange cases for counts */ |
| 69 |
if (offset != 0) |
| 70 |
{ |
| 71 |
isfillormix = ((opcode == 2) || (opcode == 7)); |
| 72 |
|
| 73 |
if (count == 0) |
| 74 |
{ |
| 75 |
if (isfillormix) |
| 76 |
count = CVAL(input) + 1; |
| 77 |
else |
| 78 |
count = CVAL(input) + offset; |
| 79 |
} |
| 80 |
else if (isfillormix) |
| 81 |
{ |
| 82 |
count <<= 3; |
| 83 |
} |
| 84 |
} |
| 85 |
|
| 86 |
/* Read preliminary data */ |
| 87 |
mixmask = 0; |
| 88 |
switch (opcode) |
| 89 |
{ |
| 90 |
case 0: /* Fill */ |
| 91 |
if ((lastopcode == opcode) && (x != width)) |
| 92 |
insertmix = True; |
| 93 |
break; |
| 94 |
case 8: /* Bicolour */ |
| 95 |
colour1 = CVAL(input); |
| 96 |
case 3: /* Colour */ |
| 97 |
colour2 = CVAL(input); |
| 98 |
break; |
| 99 |
case 6: /* SetMix/Mix */ |
| 100 |
case 7: /* SetMix/FillOrMix */ |
| 101 |
mix = CVAL(input); |
| 102 |
opcode -= 5; |
| 103 |
break; |
| 104 |
} |
| 105 |
lastopcode = opcode; |
| 106 |
|
| 107 |
/* Output body */ |
| 108 |
while (count > 0) |
| 109 |
{ |
| 110 |
if (x >= width) |
| 111 |
{ |
| 112 |
if (height <= 0) |
| 113 |
return False; |
| 114 |
|
| 115 |
x = 0; |
| 116 |
height--; |
| 117 |
|
| 118 |
prevline = line; |
| 119 |
line = output + height * width; |
| 120 |
} |
| 121 |
|
| 122 |
switch (opcode) |
| 123 |
{ |
| 124 |
case 0: /* Fill */ |
| 125 |
if (insertmix) |
| 126 |
{ |
| 127 |
if (prevline == NULL) |
| 128 |
line[x] = mix; |
| 129 |
else |
| 130 |
line[x] = prevline[x] ^ mix; |
| 131 |
|
| 132 |
insertmix = False; |
| 133 |
count--; |
| 134 |
x++; |
| 135 |
} |
| 136 |
|
| 137 |
if (prevline == NULL) |
| 138 |
REPEAT(line[x] = 0) |
| 139 |
else |
| 140 |
REPEAT(line[x] = prevline[x]) |
| 141 |
break; |
| 142 |
|
| 143 |
case 1: /* Mix */ |
| 144 |
if (prevline == NULL) |
| 145 |
REPEAT(line[x] = mix) |
| 146 |
else |
| 147 |
REPEAT(line[x] = prevline[x] ^ mix) |
| 148 |
break; |
| 149 |
|
| 150 |
case 2: /* Fill or Mix */ |
| 151 |
if (prevline == NULL) |
| 152 |
REPEAT( |
| 153 |
MASK_UPDATE(); |
| 154 |
|
| 155 |
if (mask & mixmask) |
| 156 |
line[x] = mix; |
| 157 |
else |
| 158 |
line[x] = 0; |
| 159 |
) |
| 160 |
else |
| 161 |
REPEAT( |
| 162 |
MASK_UPDATE(); |
| 163 |
|
| 164 |
if (mask & mixmask) |
| 165 |
line[x] = prevline[x] ^ mix; |
| 166 |
else |
| 167 |
line[x] = prevline[x]; |
| 168 |
) |
| 169 |
break; |
| 170 |
|
| 171 |
case 3: /* Colour */ |
| 172 |
REPEAT(line[x] = colour2) |
| 173 |
break; |
| 174 |
|
| 175 |
case 4: /* Copy */ |
| 176 |
REPEAT(line[x] = CVAL(input)) |
| 177 |
break; |
| 178 |
|
| 179 |
case 8: /* Bicolour */ |
| 180 |
REPEAT(line[x] = colour1; line[++x] = colour2) |
| 181 |
break; |
| 182 |
|
| 183 |
case 13: /* White */ |
| 184 |
REPEAT(line[x] = 0xff) |
| 185 |
break; |
| 186 |
|
| 187 |
case 14: /* Black */ |
| 188 |
REPEAT(line[x] = 0x00) |
| 189 |
break; |
| 190 |
|
| 191 |
default: |
| 192 |
NOTIMP("bitmap opcode 0x%x\n", opcode); |
| 193 |
return False; |
| 194 |
} |
| 195 |
} |
| 196 |
} |
| 197 |
|
| 198 |
return True; |
| 199 |
} |
Parent Directory
| 
Revision Log