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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  /* update state */
152  state->A[Q] += FFABS(ret) - RItype;
153  ret *= state->twonear;
154  ff_jpegls_downscale_state(state, Q);
155 
156  return ret;
157 }
158 
159 /**
160  * Decode one line of image
161  */
163  void *last, void *dst, int last2, int w,
164  int stride, int comp, int bits)
165 {
166  int i, x = 0;
167  int Ra, Rb, Rc, Rd;
168  int D0, D1, D2;
169 
170  while (x < w) {
171  int err, pred;
172 
173  /* compute gradients */
174  Ra = x ? R(dst, x - stride) : R(last, x);
175  Rb = R(last, x);
176  Rc = x ? R(last, x - stride) : last2;
177  Rd = (x >= w - stride) ? R(last, x) : R(last, x + stride);
178  D0 = Rd - Rb;
179  D1 = Rb - Rc;
180  D2 = Rc - Ra;
181  /* run mode */
182  if ((FFABS(D0) <= state->near) &&
183  (FFABS(D1) <= state->near) &&
184  (FFABS(D2) <= state->near)) {
185  int r;
186  int RItype;
187 
188  /* decode full runs while available */
189  while (get_bits1(&s->gb)) {
190  int r;
191  r = 1 << ff_log2_run[state->run_index[comp]];
192  if (x + r * stride > w)
193  r = (w - x) / stride;
194  for (i = 0; i < r; i++) {
195  W(dst, x, Ra);
196  x += stride;
197  }
198  /* if EOL reached, we stop decoding */
199  if (r != 1 << ff_log2_run[state->run_index[comp]])
200  return;
201  if (state->run_index[comp] < 31)
202  state->run_index[comp]++;
203  if (x + stride > w)
204  return;
205  }
206  /* decode aborted run */
207  r = ff_log2_run[state->run_index[comp]];
208  if (r)
209  r = get_bits_long(&s->gb, r);
210  if (x + r * stride > w) {
211  r = (w - x) / stride;
212  }
213  for (i = 0; i < r; i++) {
214  W(dst, x, Ra);
215  x += stride;
216  }
217 
218  /* decode run termination value */
219  Rb = R(last, x);
220  RItype = (FFABS(Ra - Rb) <= state->near) ? 1 : 0;
221  err = ls_get_code_runterm(&s->gb, state, RItype,
222  ff_log2_run[state->run_index[comp]]);
223  if (state->run_index[comp])
224  state->run_index[comp]--;
225 
226  if (state->near && RItype) {
227  pred = Ra + err;
228  } else {
229  if (Rb < Ra)
230  pred = Rb - err;
231  else
232  pred = Rb + err;
233  }
234  } else { /* regular mode */
235  int context, sign;
236 
237  context = ff_jpegls_quantize(state, D0) * 81 +
238  ff_jpegls_quantize(state, D1) * 9 +
239  ff_jpegls_quantize(state, D2);
240  pred = mid_pred(Ra, Ra + Rb - Rc, Rb);
241 
242  if (context < 0) {
243  context = -context;
244  sign = 1;
245  } else {
246  sign = 0;
247  }
248 
249  if (sign) {
250  pred = av_clip(pred - state->C[context], 0, state->maxval);
251  err = -ls_get_code_regular(&s->gb, state, context);
252  } else {
253  pred = av_clip(pred + state->C[context], 0, state->maxval);
254  err = ls_get_code_regular(&s->gb, state, context);
255  }
256 
257  /* we have to do something more for near-lossless coding */
258  pred += err;
259  }
260  if (state->near) {
261  if (pred < -state->near)
262  pred += state->range * state->twonear;
263  else if (pred > state->maxval + state->near)
264  pred -= state->range * state->twonear;
265  pred = av_clip(pred, 0, state->maxval);
266  }
267 
268  pred &= state->maxval;
269  W(dst, x, pred);
270  x += stride;
271  }
272 }
273 
275  int point_transform, int ilv)
276 {
277  int i, t = 0;
278  uint8_t *zero, *last, *cur;
279  JLSState *state;
280  int off = 0, stride = 1, width, shift, ret = 0;
281 
282  zero = av_mallocz(s->picture.linesize[0]);
283  last = zero;
284  cur = s->picture.data[0];
285 
286  state = av_mallocz(sizeof(JLSState));
287  /* initialize JPEG-LS state from JPEG parameters */
288  state->near = near;
289  state->bpp = (s->bits < 2) ? 2 : s->bits;
290  state->maxval = s->maxval;
291  state->T1 = s->t1;
292  state->T2 = s->t2;
293  state->T3 = s->t3;
294  state->reset = s->reset;
296  ff_jpegls_init_state(state);
297 
298  if (s->bits <= 8)
299  shift = point_transform + (8 - s->bits);
300  else
301  shift = point_transform + (16 - s->bits);
302 
303  if (s->avctx->debug & FF_DEBUG_PICT_INFO) {
305  "JPEG-LS params: %ix%i NEAR=%i MV=%i T(%i,%i,%i) "
306  "RESET=%i, LIMIT=%i, qbpp=%i, RANGE=%i\n",
307  s->width, s->height, state->near, state->maxval,
308  state->T1, state->T2, state->T3,
309  state->reset, state->limit, state->qbpp, state->range);
310  av_log(s->avctx, AV_LOG_DEBUG, "JPEG params: ILV=%i Pt=%i BPP=%i, scan = %i\n",
311  ilv, point_transform, s->bits, s->cur_scan);
312  }
313  if (ilv == 0) { /* separate planes */
314  if (s->cur_scan > s->nb_components) {
315  ret = AVERROR_INVALIDDATA;
316  goto end;
317  }
318  stride = (s->nb_components > 1) ? 3 : 1;
319  off = av_clip(s->cur_scan - 1, 0, stride - 1);
320  width = s->width * stride;
321  cur += off;
322  for (i = 0; i < s->height; i++) {
323  if (s->bits <= 8) {
324  ls_decode_line(state, s, last, cur, t, width, stride, off, 8);
325  t = last[0];
326  } else {
327  ls_decode_line(state, s, last, cur, t, width, stride, off, 16);
328  t = *((uint16_t *)last);
329  }
330  last = cur;
331  cur += s->picture.linesize[0];
332 
333  if (s->restart_interval && !--s->restart_count) {
334  align_get_bits(&s->gb);
335  skip_bits(&s->gb, 16); /* skip RSTn */
336  }
337  }
338  } else if (ilv == 1) { /* line interleaving */
339  int j;
340  int Rc[3] = { 0, 0, 0 };
341  stride = (s->nb_components > 1) ? 3 : 1;
342  memset(cur, 0, s->picture.linesize[0]);
343  width = s->width * stride;
344  for (i = 0; i < s->height; i++) {
345  for (j = 0; j < stride; j++) {
346  ls_decode_line(state, s, last + j, cur + j,
347  Rc[j], width, stride, j, 8);
348  Rc[j] = last[j];
349 
350  if (s->restart_interval && !--s->restart_count) {
351  align_get_bits(&s->gb);
352  skip_bits(&s->gb, 16); /* skip RSTn */
353  }
354  }
355  last = cur;
356  cur += s->picture.linesize[0];
357  }
358  } else if (ilv == 2) { /* sample interleaving */
359  avpriv_report_missing_feature(s->avctx, "Sample interleaved images");
360  ret = AVERROR_PATCHWELCOME;
361  goto end;
362  }
363 
364  if (shift) { /* we need to do point transform or normalize samples */
365  int x, w;
366 
367  w = s->width * s->nb_components;
368 
369  if (s->bits <= 8) {
370  uint8_t *src = s->picture.data[0];
371 
372  for (i = 0; i < s->height; i++) {
373  for (x = off; x < w; x += stride)
374  src[x] <<= shift;
375  src += s->picture.linesize[0];
376  }
377  } else {
378  uint16_t *src = (uint16_t *)s->picture.data[0];
379 
380  for (i = 0; i < s->height; i++) {
381  for (x = 0; x < w; x++)
382  src[x] <<= shift;
383  src += s->picture.linesize[0] / 2;
384  }
385  }
386  }
387 
388 end:
389  av_free(state);
390  av_free(zero);
391 
392  return ret;
393 }
394 
396  .name = "jpegls",
397  .long_name = NULL_IF_CONFIG_SMALL("JPEG-LS"),
398  .type = AVMEDIA_TYPE_VIDEO,
399  .id = AV_CODEC_ID_JPEGLS,
400  .priv_data_size = sizeof(MJpegDecodeContext),
404  .capabilities = CODEC_CAP_DR1,
405 };