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jpeglsdec.c
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1 /*
2  * JPEG-LS decoder
3  * Copyright (c) 2003 Michael Niedermayer
4  * Copyright (c) 2006 Konstantin Shishkov
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 /**
24  * @file
25  * JPEG-LS decoder.
26  */
27 
28 #include "avcodec.h"
29 #include "get_bits.h"
30 #include "golomb.h"
31 #include "mathops.h"
32 #include "mjpeg.h"
33 #include "mjpegdec.h"
34 #include "jpegls.h"
35 #include "jpeglsdec.h"
36 
37 /*
38  * Uncomment this to significantly speed up decoding of broken JPEG-LS
39  * (or test broken JPEG-LS decoder) and slow down ordinary decoding a bit.
40  *
41  * There is no Golomb code with length >= 32 bits possible, so check and
42  * avoid situation of 32 zeros, FFmpeg Golomb decoder is painfully slow
43  * on this errors.
44  */
45 //#define JLS_BROKEN
46 
47 /**
48  * Decode LSE block with initialization parameters
49  */
51 {
52  int id;
53 
54  skip_bits(&s->gb, 16); /* length: FIXME: verify field validity */
55  id = get_bits(&s->gb, 8);
56 
57  switch (id) {
58  case 1:
59  s->maxval = get_bits(&s->gb, 16);
60  s->t1 = get_bits(&s->gb, 16);
61  s->t2 = get_bits(&s->gb, 16);
62  s->t3 = get_bits(&s->gb, 16);
63  s->reset = get_bits(&s->gb, 16);
64 
65 // ff_jpegls_reset_coding_parameters(s, 0);
66  //FIXME quant table?
67  break;
68  case 2:
69  case 3:
70  av_log(s->avctx, AV_LOG_ERROR, "palette not supported\n");
71  return AVERROR(ENOSYS);
72  case 4:
73  av_log(s->avctx, AV_LOG_ERROR, "oversize image not supported\n");
74  return AVERROR(ENOSYS);
75  default:
76  av_log(s->avctx, AV_LOG_ERROR, "invalid id %d\n", id);
77  return AVERROR_INVALIDDATA;
78  }
79  av_dlog(s->avctx, "ID=%i, T=%i,%i,%i\n", id, s->t1, s->t2, s->t3);
80 
81  return 0;
82 }
83 
84 /**
85  * Get context-dependent Golomb code, decode it and update context
86  */
87 static inline int ls_get_code_regular(GetBitContext *gb, JLSState *state, int Q)
88 {
89  int k, ret;
90 
91  for (k = 0; (state->N[Q] << k) < state->A[Q]; k++)
92  ;
93 
94 #ifdef JLS_BROKEN
95  if (!show_bits_long(gb, 32))
96  return -1;
97 #endif
98  ret = get_ur_golomb_jpegls(gb, k, state->limit, state->qbpp);
99 
100  /* decode mapped error */
101  if (ret & 1)
102  ret = -(ret + 1 >> 1);
103  else
104  ret >>= 1;
105 
106  /* for NEAR=0, k=0 and 2*B[Q] <= - N[Q] mapping is reversed */
107  if (!state->near && !k && (2 * state->B[Q] <= -state->N[Q]))
108  ret = -(ret + 1);
109 
110  ret = ff_jpegls_update_state_regular(state, Q, ret);
111 
112  return ret;
113 }
114 
115 /**
116  * Get Golomb code, decode it and update state for run termination
117  */
119  int RItype, int limit_add)
120 {
121  int k, ret, temp, map;
122  int Q = 365 + RItype;
123 
124  temp = state->A[Q];
125  if (RItype)
126  temp += state->N[Q] >> 1;
127 
128  for (k = 0; (state->N[Q] << k) < temp; k++)
129  ;
130 
131 #ifdef JLS_BROKEN
132  if (!show_bits_long(gb, 32))
133  return -1;
134 #endif
135  ret = get_ur_golomb_jpegls(gb, k, state->limit - limit_add - 1,
136  state->qbpp);
137 
138  /* decode mapped error */
139  map = 0;
140  if (!k && (RItype || ret) && (2 * state->B[Q] < state->N[Q]))
141  map = 1;
142  ret += RItype + map;
143 
144  if (ret & 1) {
145  ret = map - (ret + 1 >> 1);
146  state->B[Q]++;
147  } else {
148  ret = ret >> 1;
149  }
150 
151  if(FFABS(ret) > 0xFFFF)
152  return -0x10000;
153  /* update state */
154  state->A[Q] += FFABS(ret) - RItype;
155  ret *= state->twonear;
156  ff_jpegls_downscale_state(state, Q);
157 
158  return ret;
159 }
160 
161 /**
162  * Decode one line of image
163  */
165  void *last, void *dst, int last2, int w,
166  int stride, int comp, int bits)
167 {
168  int i, x = 0;
169  int Ra, Rb, Rc, Rd;
170  int D0, D1, D2;
171 
172  while (x < w) {
173  int err, pred;
174 
175  /* compute gradients */
176  Ra = x ? R(dst, x - stride) : R(last, x);
177  Rb = R(last, x);
178  Rc = x ? R(last, x - stride) : last2;
179  Rd = (x >= w - stride) ? R(last, x) : R(last, x + stride);
180  D0 = Rd - Rb;
181  D1 = Rb - Rc;
182  D2 = Rc - Ra;
183  /* run mode */
184  if ((FFABS(D0) <= state->near) &&
185  (FFABS(D1) <= state->near) &&
186  (FFABS(D2) <= state->near)) {
187  int r;
188  int RItype;
189 
190  /* decode full runs while available */
191  while (get_bits1(&s->gb)) {
192  int r;
193  r = 1 << ff_log2_run[state->run_index[comp]];
194  if (x + r * stride > w)
195  r = (w - x) / stride;
196  for (i = 0; i < r; i++) {
197  W(dst, x, Ra);
198  x += stride;
199  }
200  /* if EOL reached, we stop decoding */
201  if (r != 1 << ff_log2_run[state->run_index[comp]])
202  return;
203  if (state->run_index[comp] < 31)
204  state->run_index[comp]++;
205  if (x + stride > w)
206  return;
207  }
208  /* decode aborted run */
209  r = ff_log2_run[state->run_index[comp]];
210  if (r)
211  r = get_bits_long(&s->gb, r);
212  if (x + r * stride > w) {
213  r = (w - x) / stride;
214  }
215  for (i = 0; i < r; i++) {
216  W(dst, x, Ra);
217  x += stride;
218  }
219 
220  /* decode run termination value */
221  Rb = R(last, x);
222  RItype = (FFABS(Ra - Rb) <= state->near) ? 1 : 0;
223  err = ls_get_code_runterm(&s->gb, state, RItype,
224  ff_log2_run[state->run_index[comp]]);
225  if (state->run_index[comp])
226  state->run_index[comp]--;
227 
228  if (state->near && RItype) {
229  pred = Ra + err;
230  } else {
231  if (Rb < Ra)
232  pred = Rb - err;
233  else
234  pred = Rb + err;
235  }
236  } else { /* regular mode */
237  int context, sign;
238 
239  context = ff_jpegls_quantize(state, D0) * 81 +
240  ff_jpegls_quantize(state, D1) * 9 +
241  ff_jpegls_quantize(state, D2);
242  pred = mid_pred(Ra, Ra + Rb - Rc, Rb);
243 
244  if (context < 0) {
245  context = -context;
246  sign = 1;
247  } else {
248  sign = 0;
249  }
250 
251  if (sign) {
252  pred = av_clip(pred - state->C[context], 0, state->maxval);
253  err = -ls_get_code_regular(&s->gb, state, context);
254  } else {
255  pred = av_clip(pred + state->C[context], 0, state->maxval);
256  err = ls_get_code_regular(&s->gb, state, context);
257  }
258 
259  /* we have to do something more for near-lossless coding */
260  pred += err;
261  }
262  if (state->near) {
263  if (pred < -state->near)
264  pred += state->range * state->twonear;
265  else if (pred > state->maxval + state->near)
266  pred -= state->range * state->twonear;
267  pred = av_clip(pred, 0, state->maxval);
268  }
269 
270  pred &= state->maxval;
271  W(dst, x, pred);
272  x += stride;
273  }
274 }
275 
277  int point_transform, int ilv)
278 {
279  int i, t = 0;
280  uint8_t *zero, *last, *cur;
281  JLSState *state;
282  int off = 0, stride = 1, width, shift, ret = 0;
283 
284  zero = av_mallocz(s->picture_ptr->linesize[0]);
285  last = zero;
286  cur = s->picture_ptr->data[0];
287 
288  state = av_mallocz(sizeof(JLSState));
289  /* initialize JPEG-LS state from JPEG parameters */
290  state->near = near;
291  state->bpp = (s->bits < 2) ? 2 : s->bits;
292  state->maxval = s->maxval;
293  state->T1 = s->t1;
294  state->T2 = s->t2;
295  state->T3 = s->t3;
296  state->reset = s->reset;
298  ff_jpegls_init_state(state);
299 
300  if (s->bits <= 8)
301  shift = point_transform + (8 - s->bits);
302  else
303  shift = point_transform + (16 - s->bits);
304 
305  if (s->avctx->debug & FF_DEBUG_PICT_INFO) {
307  "JPEG-LS params: %ix%i NEAR=%i MV=%i T(%i,%i,%i) "
308  "RESET=%i, LIMIT=%i, qbpp=%i, RANGE=%i\n",
309  s->width, s->height, state->near, state->maxval,
310  state->T1, state->T2, state->T3,
311  state->reset, state->limit, state->qbpp, state->range);
312  av_log(s->avctx, AV_LOG_DEBUG, "JPEG params: ILV=%i Pt=%i BPP=%i, scan = %i\n",
313  ilv, point_transform, s->bits, s->cur_scan);
314  }
315  if (ilv == 0) { /* separate planes */
316  if (s->cur_scan > s->nb_components) {
317  ret = AVERROR_INVALIDDATA;
318  goto end;
319  }
320  stride = (s->nb_components > 1) ? 3 : 1;
321  off = av_clip(s->cur_scan - 1, 0, stride - 1);
322  width = s->width * stride;
323  cur += off;
324  for (i = 0; i < s->height; i++) {
325  if (s->bits <= 8) {
326  ls_decode_line(state, s, last, cur, t, width, stride, off, 8);
327  t = last[0];
328  } else {
329  ls_decode_line(state, s, last, cur, t, width, stride, off, 16);
330  t = *((uint16_t *)last);
331  }
332  last = cur;
333  cur += s->picture_ptr->linesize[0];
334 
335  if (s->restart_interval && !--s->restart_count) {
336  align_get_bits(&s->gb);
337  skip_bits(&s->gb, 16); /* skip RSTn */
338  }
339  }
340  } else if (ilv == 1) { /* line interleaving */
341  int j;
342  int Rc[3] = { 0, 0, 0 };
343  stride = (s->nb_components > 1) ? 3 : 1;
344  memset(cur, 0, s->picture_ptr->linesize[0]);
345  width = s->width * stride;
346  for (i = 0; i < s->height; i++) {
347  for (j = 0; j < stride; j++) {
348  ls_decode_line(state, s, last + j, cur + j,
349  Rc[j], width, stride, j, 8);
350  Rc[j] = last[j];
351 
352  if (s->restart_interval && !--s->restart_count) {
353  align_get_bits(&s->gb);
354  skip_bits(&s->gb, 16); /* skip RSTn */
355  }
356  }
357  last = cur;
358  cur += s->picture_ptr->linesize[0];
359  }
360  } else if (ilv == 2) { /* sample interleaving */
361  avpriv_report_missing_feature(s->avctx, "Sample interleaved images");
362  ret = AVERROR_PATCHWELCOME;
363  goto end;
364  }
365 
366  if (s->xfrm && s->nb_components == 3) {
367  int x, w;
368 
369  w = s->width * s->nb_components;
370 
371  if (s->bits <= 8) {
372  uint8_t *src = s->picture_ptr->data[0];
373 
374  for (i = 0; i < s->height; i++) {
375  switch(s->xfrm) {
376  case 1:
377  for (x = off; x < w; x += 3) {
378  src[x ] += src[x+1] + 128;
379  src[x+2] += src[x+1] + 128;
380  }
381  break;
382  case 2:
383  for (x = off; x < w; x += 3) {
384  src[x ] += src[x+1] + 128;
385  src[x+2] += ((src[x ] + src[x+1])>>1) + 128;
386  }
387  break;
388  case 3:
389  for (x = off; x < w; x += 3) {
390  int g = src[x+0] - ((src[x+2]+src[x+1])>>2) + 64;
391  src[x+0] = src[x+2] + g + 128;
392  src[x+2] = src[x+1] + g + 128;
393  src[x+1] = g;
394  }
395  break;
396  case 4:
397  for (x = off; x < w; x += 3) {
398  int r = src[x+0] - (( 359 * (src[x+2]-128) + 490) >> 8);
399  int g = src[x+0] - (( 88 * (src[x+1]-128) - 183 * (src[x+2]-128) + 30) >> 8);
400  int b = src[x+0] + ((454 * (src[x+1]-128) + 574) >> 8);
401  src[x+0] = av_clip_uint8(r);
402  src[x+1] = av_clip_uint8(g);
403  src[x+2] = av_clip_uint8(b);
404  }
405  break;
406  }
407  src += s->picture_ptr->linesize[0];
408  }
409  }else
410  avpriv_report_missing_feature(s->avctx, "16bit xfrm");
411  }
412 
413  if (shift) { /* we need to do point transform or normalize samples */
414  int x, w;
415 
416  w = s->width * s->nb_components;
417 
418  if (s->bits <= 8) {
419  uint8_t *src = s->picture_ptr->data[0];
420 
421  for (i = 0; i < s->height; i++) {
422  for (x = off; x < w; x += stride)
423  src[x] <<= shift;
424  src += s->picture_ptr->linesize[0];
425  }
426  } else {
427  uint16_t *src = (uint16_t *)s->picture_ptr->data[0];
428 
429  for (i = 0; i < s->height; i++) {
430  for (x = 0; x < w; x++)
431  src[x] <<= shift;
432  src += s->picture_ptr->linesize[0] / 2;
433  }
434  }
435  }
436 
437 end:
438  av_free(state);
439  av_free(zero);
440 
441  return ret;
442 }
443 
445  .name = "jpegls",
446  .long_name = NULL_IF_CONFIG_SMALL("JPEG-LS"),
447  .type = AVMEDIA_TYPE_VIDEO,
448  .id = AV_CODEC_ID_JPEGLS,
449  .priv_data_size = sizeof(MJpegDecodeContext),
453  .capabilities = CODEC_CAP_DR1,
454 };