jpeglsenc.c
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1 /*
2  * JPEG-LS encoder
3  * Copyright (c) 2003 Michael Niedermayer
4  * Copyright (c) 2006 Konstantin Shishkov
5  *
6  * This file is part of Libav.
7  *
8  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
28 #include "avcodec.h"
29 #include "get_bits.h"
30 #include "golomb.h"
31 #include "mathops.h"
32 #include "dsputil.h"
33 #include "mjpeg.h"
34 #include "jpegls.h"
35 
36 
40 static inline void ls_encode_regular(JLSState *state, PutBitContext *pb, int Q, int err){
41  int k;
42  int val;
43  int map;
44 
45  for(k = 0; (state->N[Q] << k) < state->A[Q]; k++);
46 
47  map = !state->near && !k && (2 * state->B[Q] <= -state->N[Q]);
48 
49  if(err < 0)
50  err += state->range;
51  if(err >= ((state->range + 1) >> 1)) {
52  err -= state->range;
53  val = 2 * FFABS(err) - 1 - map;
54  } else
55  val = 2 * err + map;
56 
57  set_ur_golomb_jpegls(pb, val, k, state->limit, state->qbpp);
58 
59  ff_jpegls_update_state_regular(state, Q, err);
60 }
61 
65 static inline void ls_encode_runterm(JLSState *state, PutBitContext *pb, int RItype, int err, int limit_add){
66  int k;
67  int val, map;
68  int Q = 365 + RItype;
69  int temp;
70 
71  temp = state->A[Q];
72  if(RItype)
73  temp += state->N[Q] >> 1;
74  for(k = 0; (state->N[Q] << k) < temp; k++);
75  map = 0;
76  if(!k && err && (2 * state->B[Q] < state->N[Q]))
77  map = 1;
78 
79  if(err < 0)
80  val = - (2 * err) - 1 - RItype + map;
81  else
82  val = 2 * err - RItype - map;
83  set_ur_golomb_jpegls(pb, val, k, state->limit - limit_add - 1, state->qbpp);
84 
85  if(err < 0)
86  state->B[Q]++;
87  state->A[Q] += (val + 1 - RItype) >> 1;
88 
89  ff_jpegls_downscale_state(state, Q);
90 }
91 
95 static inline void ls_encode_run(JLSState *state, PutBitContext *pb, int run, int comp, int trail){
96  while(run >= (1 << ff_log2_run[state->run_index[comp]])){
97  put_bits(pb, 1, 1);
98  run -= 1 << ff_log2_run[state->run_index[comp]];
99  if(state->run_index[comp] < 31)
100  state->run_index[comp]++;
101  }
102  /* if hit EOL, encode another full run, else encode aborted run */
103  if(!trail && run) {
104  put_bits(pb, 1, 1);
105  }else if(trail){
106  put_bits(pb, 1, 0);
107  if(ff_log2_run[state->run_index[comp]])
108  put_bits(pb, ff_log2_run[state->run_index[comp]], run);
109  }
110 }
111 
115 static inline void ls_encode_line(JLSState *state, PutBitContext *pb, void *last, void *cur, int last2, int w, int stride, int comp, int bits){
116  int x = 0;
117  int Ra, Rb, Rc, Rd;
118  int D0, D1, D2;
119 
120  while(x < w) {
121  int err, pred, sign;
122 
123  /* compute gradients */
124  Ra = x ? R(cur, x - stride) : R(last, x);
125  Rb = R(last, x);
126  Rc = x ? R(last, x - stride) : last2;
127  Rd = (x >= w - stride) ? R(last, x) : R(last, x + stride);
128  D0 = Rd - Rb;
129  D1 = Rb - Rc;
130  D2 = Rc - Ra;
131 
132  /* run mode */
133  if((FFABS(D0) <= state->near) && (FFABS(D1) <= state->near) && (FFABS(D2) <= state->near)) {
134  int RUNval, RItype, run;
135 
136  run = 0;
137  RUNval = Ra;
138  while(x < w && (FFABS(R(cur, x) - RUNval) <= state->near)){
139  run++;
140  W(cur, x, Ra);
141  x += stride;
142  }
143  ls_encode_run(state, pb, run, comp, x < w);
144  if(x >= w)
145  return;
146  Rb = R(last, x);
147  RItype = (FFABS(Ra - Rb) <= state->near);
148  pred = RItype ? Ra : Rb;
149  err = R(cur, x) - pred;
150 
151  if(!RItype && Ra > Rb)
152  err = -err;
153 
154  if(state->near){
155  if(err > 0)
156  err = (state->near + err) / state->twonear;
157  else
158  err = -(state->near - err) / state->twonear;
159 
160  if(RItype || (Rb >= Ra))
161  Ra = av_clip(pred + err * state->twonear, 0, state->maxval);
162  else
163  Ra = av_clip(pred - err * state->twonear, 0, state->maxval);
164  W(cur, x, Ra);
165  }
166  if(err < 0)
167  err += state->range;
168  if(err >= ((state->range + 1) >> 1))
169  err -= state->range;
170 
171  ls_encode_runterm(state, pb, RItype, err, ff_log2_run[state->run_index[comp]]);
172 
173  if(state->run_index[comp] > 0)
174  state->run_index[comp]--;
175  } else { /* regular mode */
176  int context;
177 
178  context = ff_jpegls_quantize(state, D0) * 81 + ff_jpegls_quantize(state, D1) * 9 + ff_jpegls_quantize(state, D2);
179  pred = mid_pred(Ra, Ra + Rb - Rc, Rb);
180 
181  if(context < 0){
182  context = -context;
183  sign = 1;
184  pred = av_clip(pred - state->C[context], 0, state->maxval);
185  err = pred - R(cur, x);
186  }else{
187  sign = 0;
188  pred = av_clip(pred + state->C[context], 0, state->maxval);
189  err = R(cur, x) - pred;
190  }
191 
192  if(state->near){
193  if(err > 0)
194  err = (state->near + err) / state->twonear;
195  else
196  err = -(state->near - err) / state->twonear;
197  if(!sign)
198  Ra = av_clip(pred + err * state->twonear, 0, state->maxval);
199  else
200  Ra = av_clip(pred - err * state->twonear, 0, state->maxval);
201  W(cur, x, Ra);
202  }
203 
204  ls_encode_regular(state, pb, context, err);
205  }
206  x += stride;
207  }
208 }
209 
211  /* Test if we have default params and don't need to store LSE */
212  JLSState state2;
213  memset(&state2, 0, sizeof(JLSState));
214  state2.bpp = state->bpp;
215  state2.near = state->near;
217  if(state->T1 == state2.T1 && state->T2 == state2.T2 && state->T3 == state2.T3 && state->reset == state2.reset)
218  return;
219  /* store LSE type 1 */
220  put_marker(pb, LSE);
221  put_bits(pb, 16, 13);
222  put_bits(pb, 8, 1);
223  put_bits(pb, 16, state->maxval);
224  put_bits(pb, 16, state->T1);
225  put_bits(pb, 16, state->T2);
226  put_bits(pb, 16, state->T3);
227  put_bits(pb, 16, state->reset);
228 }
229 
230 static int encode_picture_ls(AVCodecContext *avctx, unsigned char *buf, int buf_size, void *data){
231  JpeglsContext * const s = avctx->priv_data;
232  AVFrame *pict = data;
233  AVFrame * const p= (AVFrame*)&s->picture;
234  const int near = avctx->prediction_method;
235  PutBitContext pb, pb2;
236  GetBitContext gb;
237  uint8_t *buf2, *zero, *cur, *last;
238  JLSState *state;
239  int i, size;
240  int comps;
241 
242  buf2 = av_malloc(buf_size);
243 
244  init_put_bits(&pb, buf, buf_size);
245  init_put_bits(&pb2, buf2, buf_size);
246 
247  *p = *pict;
249  p->key_frame= 1;
250 
251  if(avctx->pix_fmt == PIX_FMT_GRAY8 || avctx->pix_fmt == PIX_FMT_GRAY16)
252  comps = 1;
253  else
254  comps = 3;
255 
256  /* write our own JPEG header, can't use mjpeg_picture_header */
257  put_marker(&pb, SOI);
258  put_marker(&pb, SOF48);
259  put_bits(&pb, 16, 8 + comps * 3); // header size depends on components
260  put_bits(&pb, 8, (avctx->pix_fmt == PIX_FMT_GRAY16) ? 16 : 8); // bpp
261  put_bits(&pb, 16, avctx->height);
262  put_bits(&pb, 16, avctx->width);
263  put_bits(&pb, 8, comps); // components
264  for(i = 1; i <= comps; i++) {
265  put_bits(&pb, 8, i); // component ID
266  put_bits(&pb, 8, 0x11); // subsampling: none
267  put_bits(&pb, 8, 0); // Tiq, used by JPEG-LS ext
268  }
269 
270  put_marker(&pb, SOS);
271  put_bits(&pb, 16, 6 + comps * 2);
272  put_bits(&pb, 8, comps);
273  for(i = 1; i <= comps; i++) {
274  put_bits(&pb, 8, i); // component ID
275  put_bits(&pb, 8, 0); // mapping index: none
276  }
277  put_bits(&pb, 8, near);
278  put_bits(&pb, 8, (comps > 1) ? 1 : 0); // interleaving: 0 - plane, 1 - line
279  put_bits(&pb, 8, 0); // point transform: none
280 
281  state = av_mallocz(sizeof(JLSState));
282  /* initialize JPEG-LS state from JPEG parameters */
283  state->near = near;
284  state->bpp = (avctx->pix_fmt == PIX_FMT_GRAY16) ? 16 : 8;
287 
288  ls_store_lse(state, &pb);
289 
290  zero = av_mallocz(p->linesize[0]);
291  last = zero;
292  cur = p->data[0];
293  if(avctx->pix_fmt == PIX_FMT_GRAY8){
294  int t = 0;
295 
296  for(i = 0; i < avctx->height; i++) {
297  ls_encode_line(state, &pb2, last, cur, t, avctx->width, 1, 0, 8);
298  t = last[0];
299  last = cur;
300  cur += p->linesize[0];
301  }
302  }else if(avctx->pix_fmt == PIX_FMT_GRAY16){
303  int t = 0;
304 
305  for(i = 0; i < avctx->height; i++) {
306  ls_encode_line(state, &pb2, last, cur, t, avctx->width, 1, 0, 16);
307  t = *((uint16_t*)last);
308  last = cur;
309  cur += p->linesize[0];
310  }
311  }else if(avctx->pix_fmt == PIX_FMT_RGB24){
312  int j, width;
313  int Rc[3] = {0, 0, 0};
314 
315  width = avctx->width * 3;
316  for(i = 0; i < avctx->height; i++) {
317  for(j = 0; j < 3; j++) {
318  ls_encode_line(state, &pb2, last + j, cur + j, Rc[j], width, 3, j, 8);
319  Rc[j] = last[j];
320  }
321  last = cur;
322  cur += s->picture.linesize[0];
323  }
324  }else if(avctx->pix_fmt == PIX_FMT_BGR24){
325  int j, width;
326  int Rc[3] = {0, 0, 0};
327 
328  width = avctx->width * 3;
329  for(i = 0; i < avctx->height; i++) {
330  for(j = 2; j >= 0; j--) {
331  ls_encode_line(state, &pb2, last + j, cur + j, Rc[j], width, 3, j, 8);
332  Rc[j] = last[j];
333  }
334  last = cur;
335  cur += s->picture.linesize[0];
336  }
337  }
338 
339  av_free(zero);
340  av_free(state);
341 
342  // the specification says that after doing 0xff escaping unused bits in the
343  // last byte must be set to 0, so just append 7 "optional" zero-bits to
344  // avoid special-casing.
345  put_bits(&pb2, 7, 0);
346  size = put_bits_count(&pb2);
347  flush_put_bits(&pb2);
348  /* do escape coding */
349  init_get_bits(&gb, buf2, size);
350  size -= 7;
351  while(get_bits_count(&gb) < size){
352  int v;
353  v = get_bits(&gb, 8);
354  put_bits(&pb, 8, v);
355  if(v == 0xFF){
356  v = get_bits(&gb, 7);
357  put_bits(&pb, 8, v);
358  }
359  }
361  av_free(buf2);
362 
363  /* End of image */
364  put_marker(&pb, EOI);
365  flush_put_bits(&pb);
366 
367  emms_c();
368 
369  return put_bits_count(&pb) >> 3;
370 }
371 
374 
375  c->avctx = ctx;
376  ctx->coded_frame = &c->picture;
377 
378  if(ctx->pix_fmt != PIX_FMT_GRAY8 && ctx->pix_fmt != PIX_FMT_GRAY16 && ctx->pix_fmt != PIX_FMT_RGB24 && ctx->pix_fmt != PIX_FMT_BGR24){
379  av_log(ctx, AV_LOG_ERROR, "Only grayscale and RGB24/BGR24 images are supported\n");
380  return -1;
381  }
382  return 0;
383 }
384 
385 AVCodec ff_jpegls_encoder = { //FIXME avoid MPV_* lossless JPEG should not need them
386  .name = "jpegls",
387  .type = AVMEDIA_TYPE_VIDEO,
388  .id = CODEC_ID_JPEGLS,
389  .priv_data_size = sizeof(JpeglsContext),
390  .init = encode_init_ls,
391  .encode = encode_picture_ls,
393  .long_name = NULL_IF_CONFIG_SMALL("JPEG-LS"),
394 };