faxcompr.c
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1 /*
2  * CCITT Fax Group 3 and 4 decompression
3  * Copyright (c) 2008 Konstantin Shishkov
4  *
5  * This file is part of Libav.
6  *
7  * Libav is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * Libav is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
27 #include "avcodec.h"
28 #include "get_bits.h"
29 #include "put_bits.h"
30 #include "faxcompr.h"
31 
32 #define CCITT_SYMS 104
33 
34 static const uint16_t ccitt_syms[CCITT_SYMS] = {
35  0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12,
36  13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25,
37  26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38,
38  39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51,
39  52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64,
40  128, 192, 256, 320, 384, 448, 512, 576, 640, 704, 768, 832, 896,
41  960, 1024, 1088, 1152, 1216, 1280, 1344, 1408, 1472, 1536, 1600, 1664, 1728,
42  1792, 1856, 1920, 1984, 2048, 2112, 2176, 2240, 2304, 2368, 2432, 2496, 2560
43 };
44 
45 static const uint8_t ccitt_codes_bits[2][CCITT_SYMS] =
46 {
47  {
48  0x35, 0x07, 0x07, 0x08, 0x0B, 0x0C, 0x0E, 0x0F, 0x13, 0x14, 0x07, 0x08, 0x08,
49  0x03, 0x34, 0x35, 0x2A, 0x2B, 0x27, 0x0C, 0x08, 0x17, 0x03, 0x04, 0x28, 0x2B,
50  0x13, 0x24, 0x18, 0x02, 0x03, 0x1A, 0x1B, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
51  0x28, 0x29, 0x2A, 0x2B, 0x2C, 0x2D, 0x04, 0x05, 0x0A, 0x0B, 0x52, 0x53, 0x54,
52  0x55, 0x24, 0x25, 0x58, 0x59, 0x5A, 0x5B, 0x4A, 0x4B, 0x32, 0x33, 0x34, 0x1B,
53  0x12, 0x17, 0x37, 0x36, 0x37, 0x64, 0x65, 0x68, 0x67, 0xCC, 0xCD, 0xD2, 0xD3,
54  0xD4, 0xD5, 0xD6, 0xD7, 0xD8, 0xD9, 0xDA, 0xDB, 0x98, 0x99, 0x9A, 0x18, 0x9B,
55  0x08, 0x0C, 0x0D, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x1C, 0x1D, 0x1E, 0x1F
56  },
57  {
58  0x37, 0x02, 0x03, 0x02, 0x03, 0x03, 0x02, 0x03, 0x05, 0x04, 0x04, 0x05, 0x07,
59  0x04, 0x07, 0x18, 0x17, 0x18, 0x08, 0x67, 0x68, 0x6C, 0x37, 0x28, 0x17, 0x18,
60  0xCA, 0xCB, 0xCC, 0xCD, 0x68, 0x69, 0x6A, 0x6B, 0xD2, 0xD3, 0xD4, 0xD5, 0xD6,
61  0xD7, 0x6C, 0x6D, 0xDA, 0xDB, 0x54, 0x55, 0x56, 0x57, 0x64, 0x65, 0x52, 0x53,
62  0x24, 0x37, 0x38, 0x27, 0x28, 0x58, 0x59, 0x2B, 0x2C, 0x5A, 0x66, 0x67, 0x0F,
63  0xC8, 0xC9, 0x5B, 0x33, 0x34, 0x35, 0x6C, 0x6D, 0x4A, 0x4B, 0x4C, 0x4D, 0x72,
64  0x73, 0x74, 0x75, 0x76, 0x77, 0x52, 0x53, 0x54, 0x55, 0x5A, 0x5B, 0x64, 0x65,
65  0x08, 0x0C, 0x0D, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x1C, 0x1D, 0x1E, 0x1F
66  }
67 };
68 
69 static const uint8_t ccitt_codes_lens[2][CCITT_SYMS] =
70 {
71  {
72  8, 6, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 6, 6, 6, 6, 6, 6, 7, 7,
73  7, 7, 7, 7, 7, 7, 7, 7, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
74  8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
75  8, 8, 8, 8, 5, 5, 6, 7, 8, 8, 8, 8, 8, 8, 9, 9, 9, 9, 9, 9,
76  9, 9, 9, 9, 9, 9, 9, 9, 9, 6, 9, 11, 11, 11, 12, 12, 12, 12, 12, 12,
77  12, 12, 12, 12
78  },
79  {
80  10, 3, 2, 2, 3, 4, 4, 5, 6, 6, 7, 7, 7, 8, 8, 9, 10, 10, 10, 11,
81  11, 11, 11, 11, 11, 11, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12,
82  12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12,
83  12, 12, 12, 12, 10, 12, 12, 12, 12, 12, 12, 13, 13, 13, 13, 13, 13, 13, 13, 13,
84  13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 11, 11, 11, 12, 12, 12, 12, 12, 12,
85  12, 12, 12, 12
86  }
87 };
88 
89 static const uint8_t ccitt_group3_2d_bits[11] = {
90  1, 1, 2, 2, 2, 1, 3, 3, 3, 1, 1
91 };
92 
93 static const uint8_t ccitt_group3_2d_lens[11] = {
94  4, 3, 7, 6, 3, 1, 3, 6, 7, 7, 9
95 };
96 
98 
100 {
101  static VLC_TYPE code_table1[528][2];
102  static VLC_TYPE code_table2[648][2];
103  int i;
104  static int initialized = 0;
105 
106  if(initialized)
107  return;
108  ccitt_vlc[0].table = code_table1;
109  ccitt_vlc[0].table_allocated = 528;
110  ccitt_vlc[1].table = code_table2;
111  ccitt_vlc[1].table_allocated = 648;
112  for(i = 0; i < 2; i++){
113  ff_init_vlc_sparse(&ccitt_vlc[i], 9, CCITT_SYMS,
114  ccitt_codes_lens[i], 1, 1,
115  ccitt_codes_bits[i], 1, 1,
116  ccitt_syms, 2, 2,
118  }
119  INIT_VLC_STATIC(&ccitt_group3_2d_vlc, 9, 11,
120  ccitt_group3_2d_lens, 1, 1,
121  ccitt_group3_2d_bits, 1, 1, 512);
122  initialized = 1;
123 }
124 
125 
127  unsigned int pix_left, int *runs, const int *runend)
128 {
129  int mode = 0;
130  unsigned int run=0;
131  unsigned int t;
132  for(;;){
133  t = get_vlc2(gb, ccitt_vlc[mode].table, 9, 2);
134  run += t;
135  if(t < 64){
136  *runs++ = run;
137  if(runs >= runend){
138  av_log(avctx, AV_LOG_ERROR, "Run overrun\n");
139  return -1;
140  }
141  if(pix_left <= run){
142  if(pix_left == run)
143  break;
144  av_log(avctx, AV_LOG_ERROR, "Run went out of bounds\n");
145  return -1;
146  }
147  pix_left -= run;
148  run = 0;
149  mode = !mode;
150  }else if((int)t == -1){
151  av_log(avctx, AV_LOG_ERROR, "Incorrect code\n");
152  return -1;
153  }
154  }
155  *runs++ = 0;
156  return 0;
157 }
158 
160  unsigned int width, int *runs, const int *runend, const int *ref)
161 {
162  int mode = 0, saved_run = 0, t;
163  int run_off = *ref++;
164  unsigned int offs=0, run= 0;
165 
166  runend--; // for the last written 0
167 
168  while(offs < width){
169  int cmode = get_vlc2(gb, ccitt_group3_2d_vlc.table, 9, 1);
170  if(cmode == -1){
171  av_log(avctx, AV_LOG_ERROR, "Incorrect mode VLC\n");
172  return -1;
173  }
174  if(!cmode){//pass mode
175  run_off += *ref++;
176  run = run_off - offs;
177  offs= run_off;
178  run_off += *ref++;
179  if(offs > width){
180  av_log(avctx, AV_LOG_ERROR, "Run went out of bounds\n");
181  return -1;
182  }
183  saved_run += run;
184  }else if(cmode == 1){//horizontal mode
185  int k;
186  for(k = 0; k < 2; k++){
187  run = 0;
188  for(;;){
189  t = get_vlc2(gb, ccitt_vlc[mode].table, 9, 2);
190  if(t == -1){
191  av_log(avctx, AV_LOG_ERROR, "Incorrect code\n");
192  return -1;
193  }
194  run += t;
195  if(t < 64)
196  break;
197  }
198  *runs++ = run + saved_run;
199  if(runs >= runend){
200  av_log(avctx, AV_LOG_ERROR, "Run overrun\n");
201  return -1;
202  }
203  saved_run = 0;
204  offs += run;
205  if(offs > width || run > width){
206  av_log(avctx, AV_LOG_ERROR, "Run went out of bounds\n");
207  return -1;
208  }
209  mode = !mode;
210  }
211  }else if(cmode == 9 || cmode == 10){
212  av_log(avctx, AV_LOG_ERROR, "Special modes are not supported (yet)\n");
213  return -1;
214  }else{//vertical mode
215  run = run_off - offs + (cmode - 5);
216  run_off -= *--ref;
217  offs += run;
218  if(offs > width || run > width){
219  av_log(avctx, AV_LOG_ERROR, "Run went out of bounds\n");
220  return -1;
221  }
222  *runs++ = run + saved_run;
223  if(runs >= runend){
224  av_log(avctx, AV_LOG_ERROR, "Run overrun\n");
225  return -1;
226  }
227  saved_run = 0;
228  mode = !mode;
229  }
230  //sync line pointers
231  while(run_off <= offs){
232  run_off += *ref++;
233  run_off += *ref++;
234  }
235  }
236  *runs++ = saved_run;
237  *runs++ = 0;
238  return 0;
239 }
240 
241 static void put_line(uint8_t *dst, int size, int width, const int *runs)
242 {
243  PutBitContext pb;
244  int run, mode = ~0, pix_left = width, run_idx = 0;
245 
246  init_put_bits(&pb, dst, size*8);
247  while(pix_left > 0){
248  run = runs[run_idx++];
249  mode = ~mode;
250  pix_left -= run;
251  for(; run > 16; run -= 16)
252  put_sbits(&pb, 16, mode);
253  if(run)
254  put_sbits(&pb, run, mode);
255  }
256  flush_put_bits(&pb);
257 }
258 
259 static int find_group3_syncmarker(GetBitContext *gb, int srcsize)
260 {
261  unsigned int state = -1;
262  srcsize -= get_bits_count(gb);
263  while(srcsize-- > 0){
264  state+= state + get_bits1(gb);
265  if((state & 0xFFF) == 1)
266  return 0;
267  }
268  return -1;
269 }
270 
272  const uint8_t *src, int srcsize,
273  uint8_t *dst, int height, int stride,
274  enum TiffCompr compr, int opts)
275 {
276  int j;
277  GetBitContext gb;
278  int *runs, *ref, *runend;
279  int ret;
280  int runsize= avctx->width + 2;
281 
282  runs = av_malloc(runsize * sizeof(runs[0]));
283  ref = av_malloc(runsize * sizeof(ref[0]));
284  ref[0] = avctx->width;
285  ref[1] = 0;
286  ref[2] = 0;
287  init_get_bits(&gb, src, srcsize*8);
288  for(j = 0; j < height; j++){
289  runend = runs + runsize;
290  if(compr == TIFF_G4){
291  ret = decode_group3_2d_line(avctx, &gb, avctx->width, runs, runend, ref);
292  if(ret < 0){
293  av_free(runs);
294  av_free(ref);
295  return -1;
296  }
297  }else{
298  int g3d1 = (compr == TIFF_G3) && !(opts & 1);
299  if(compr!=TIFF_CCITT_RLE && find_group3_syncmarker(&gb, srcsize*8) < 0)
300  break;
301  if(compr==TIFF_CCITT_RLE || g3d1 || get_bits1(&gb))
302  ret = decode_group3_1d_line(avctx, &gb, avctx->width, runs, runend);
303  else
304  ret = decode_group3_2d_line(avctx, &gb, avctx->width, runs, runend, ref);
305  if(compr==TIFF_CCITT_RLE)
306  align_get_bits(&gb);
307  }
308  if(ret < 0){
309  put_line(dst, stride, avctx->width, ref);
310  }else{
311  put_line(dst, stride, avctx->width, runs);
312  FFSWAP(int*, runs, ref);
313  }
314  dst += stride;
315  }
316  av_free(runs);
317  av_free(ref);
318  return 0;
319 }