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ffmpeg / libavcodec / jpeg_ls.c @ 81edbc1d

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1
/*
2
 * JPEG-LS encoder and decoder
3
 * Copyright (c) 2003 Michael Niedermayer
4
 * Copyright (c) 2006 Konstantin Shishkov
5
 *
6
 * This library is free software; you can redistribute it and/or
7
 * modify it under the terms of the GNU Lesser General Public
8
 * License as published by the Free Software Foundation; either
9
 * version 2 of the License, or (at your option) any later version.
10
 *
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 * This library 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 GNU
14
 * Lesser General Public License for more details.
15
 *
16
 * You should have received a copy of the GNU Lesser General Public
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 * License along with this library; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19
 */
20

    
21
#include "golomb.h"
22

    
23
/**
24
 * @file jpeg_ls.c
25
 * JPEG-LS encoder and decoder.
26
 */
27

    
28
typedef struct JpeglsContext{
29
    AVCodecContext *avctx;
30
    AVFrame picture;
31
}JpeglsContext;
32

    
33
typedef struct JLSState{
34
    int T1, T2, T3;
35
    int A[367], B[367], C[365], N[367];
36
    int limit, reset, bpp, qbpp, maxval, range;
37
    int near, twonear;
38
    int run_index[3];
39
}JLSState;
40

    
41
static const uint8_t log2_run[32]={
42
 0, 0, 0, 0, 1, 1, 1, 1,
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 2, 2, 2, 2, 3, 3, 3, 3,
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 4, 4, 5, 5, 6, 6, 7, 7,
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 8, 9,10,11,12,13,14,15
46
};
47

    
48
/*
49
* Uncomment this to significantly speed up decoding of broken JPEG-LS
50
* (or test broken JPEG-LS decoder) and slow down ordinary decoding a bit.
51
*
52
* There is no Golomb code with length >= 32 bits possible, so check and
53
* avoid situation of 32 zeros, FFmpeg Golomb decoder is painfully slow
54
* on this errors.
55
*/
56
//#define JLS_BROKEN
57

    
58
/********** Functions for both encoder and decoder **********/
59

    
60
/**
61
 * Calculate initial JPEG-LS parameters
62
 */
63
static void ls_init_state(JLSState *state){
64
    int i;
65

    
66
    state->twonear = state->near * 2 + 1;
67
    state->range = ((state->maxval + state->twonear - 1) / state->twonear) + 1;
68

    
69
    // QBPP = ceil(log2(RANGE))
70
    for(state->qbpp = 0; (1 << state->qbpp) < state->range; state->qbpp++);
71

    
72
    if(state->bpp < 8)
73
        state->limit = 16 + 2 * state->bpp - state->qbpp;
74
    else
75
        state->limit = (4 * state->bpp) - state->qbpp;
76

    
77
    for(i = 0; i < 367; i++) {
78
        state->A[i] = (state->range + 32) >> 6;
79
        if(state->A[i] < 2)
80
            state->A[i] = 2;
81
        state->N[i] = 1;
82
    }
83

    
84
}
85

    
86
/**
87
 * Calculate quantized gradient value, used for context determination
88
 */
89
static inline int quantize(JLSState *s, int v){ //FIXME optimize
90
    if(v==0) return 0;
91
    if(v < 0){
92
        if(v <= -s->T3) return -4;
93
        if(v <= -s->T2) return -3;
94
        if(v <= -s->T1) return -2;
95
        if(v <  -s->near) return -1;
96
        return 0;
97
    }else{
98
        if(v <= s->near) return 0;
99
        if(v <  s->T1) return 1;
100
        if(v <  s->T2) return 2;
101
        if(v <  s->T3) return 3;
102
        return 4;
103
    }
104
}
105

    
106
/**
107
 * Custom value clipping function used in T1, T2, T3 calculation
108
 */
109
static inline int iso_clip(int v, int vmin, int vmax){
110
    if(v > vmax || v < vmin) return vmin;
111
    else                     return v;
112
}
113

    
114
/**
115
 * Calculate JPEG-LS codec values
116
 */
117
static void reset_ls_coding_parameters(JLSState *s, int reset_all){
118
    const int basic_t1= 3;
119
    const int basic_t2= 7;
120
    const int basic_t3= 21;
121
    int factor;
122

    
123
    if(s->maxval==0 || reset_all) s->maxval= (1 << s->bpp) - 1;
124

    
125
    if(s->maxval >=128){
126
        factor= (FFMIN(s->maxval, 4095) + 128)>>8;
127

    
128
        if(s->T1==0     || reset_all)
129
            s->T1= iso_clip(factor*(basic_t1-2) + 2 + 3*s->near, s->near+1, s->maxval);
130
        if(s->T2==0     || reset_all)
131
            s->T2= iso_clip(factor*(basic_t2-3) + 3 + 5*s->near, s->T1, s->maxval);
132
        if(s->T3==0     || reset_all)
133
            s->T3= iso_clip(factor*(basic_t3-4) + 4 + 7*s->near, s->T2, s->maxval);
134
    }else{
135
        factor= 256 / (s->maxval + 1);
136

    
137
        if(s->T1==0     || reset_all)
138
            s->T1= iso_clip(FFMAX(2, basic_t1/factor + 3*s->near), s->near+1, s->maxval);
139
        if(s->T2==0     || reset_all)
140
            s->T2= iso_clip(FFMAX(3, basic_t2/factor + 5*s->near), s->T1, s->maxval);
141
        if(s->T3==0     || reset_all)
142
            s->T3= iso_clip(FFMAX(4, basic_t3/factor + 6*s->near), s->T2, s->maxval);
143
    }
144

    
145
    if(s->reset==0  || reset_all) s->reset= 64;
146
//    av_log(NULL, AV_LOG_DEBUG, "[JPEG-LS RESET] T=%i,%i,%i\n", s->T1, s->T2, s->T3);
147
}
148

    
149

    
150
/********** Decoder-specific functions **********/
151

    
152
/**
153
 * Decode LSE block with initialization parameters
154
 */
155
static int decode_lse(MJpegDecodeContext *s)
156
{
157
    int len, id;
158

    
159
    /* XXX: verify len field validity */
160
    len = get_bits(&s->gb, 16);
161
    id = get_bits(&s->gb, 8);
162

    
163
    switch(id){
164
    case 1:
165
        s->maxval= get_bits(&s->gb, 16);
166
        s->t1= get_bits(&s->gb, 16);
167
        s->t2= get_bits(&s->gb, 16);
168
        s->t3= get_bits(&s->gb, 16);
169
        s->reset= get_bits(&s->gb, 16);
170

    
171
//        reset_ls_coding_parameters(s, 0);
172
        //FIXME quant table?
173
        break;
174
    case 2:
175
    case 3:
176
        av_log(s->avctx, AV_LOG_ERROR, "palette not supported\n");
177
        return -1;
178
    case 4:
179
        av_log(s->avctx, AV_LOG_ERROR, "oversize image not supported\n");
180
        return -1;
181
    default:
182
        av_log(s->avctx, AV_LOG_ERROR, "invalid id %d\n", id);
183
        return -1;
184
    }
185
//    av_log(s->avctx, AV_LOG_DEBUG, "ID=%i, T=%i,%i,%i\n", id, s->t1, s->t2, s->t3);
186

    
187
    return 0;
188
}
189

    
190

    
191
/**
192
 * Get context-dependent Golomb code, decode it and update context
193
 */
194
static inline int ls_get_code_regular(GetBitContext *gb, JLSState *state, int Q){
195
    int k, ret;
196

    
197
    for(k = 0; (state->N[Q] << k) < state->A[Q]; k++);
198

    
199
#ifdef JLS_BROKEN
200
    if(!show_bits_long(gb, 32))return -1;
201
#endif
202
    ret = get_ur_golomb_jpegls(gb, k, state->limit, state->qbpp);
203

    
204
    /* decode mapped error */
205
    if(ret & 1)
206
        ret = -((ret + 1) >> 1);
207
    else
208
        ret >>= 1;
209

    
210
    /* for NEAR=0, k=0 and 2*B[Q] <= - N[Q] mapping is reversed */
211
    if(!state->near && !k && (2 * state->B[Q] <= -state->N[Q]))
212
        ret = -(ret + 1);
213

    
214
    state->A[Q] += ABS(ret);
215
    ret *= state->twonear;
216
    state->B[Q] += ret;
217

    
218
    if(state->N[Q] == state->reset) {
219
        state->A[Q] >>= 1;
220
        state->B[Q] >>= 1;
221
        state->N[Q] >>= 1;
222
    }
223
    state->N[Q]++;
224

    
225
    if(state->B[Q] <= -state->N[Q]) {
226
        state->B[Q] += state->N[Q];
227
        if(state->C[Q] > -128)
228
            state->C[Q]--;
229
        if(state->B[Q] <= -state->N[Q])
230
            state->B[Q] = -state->N[Q] + 1;
231
    }else if(state->B[Q] > 0){
232
        state->B[Q] -= state->N[Q];
233
        if(state->C[Q] < 127)
234
            state->C[Q]++;
235
        if(state->B[Q] > 0)
236
            state->B[Q] = 0;
237
    }
238

    
239
    return ret;
240
}
241

    
242
/**
243
 * Get Golomb code, decode it and update state for run termination
244
 */
245
static inline int ls_get_code_runterm(GetBitContext *gb, JLSState *state, int RItype, int limit_add){
246
    int k, ret, temp, map;
247
    int Q = 365 + RItype;
248

    
249
    if(!RItype)
250
        temp = state->A[Q];
251
    else
252
        temp = state->A[Q] + (state->N[Q] >> 1);
253

    
254
    for(k = 0; (state->N[Q] << k) < temp; k++);
255

    
256
#ifdef JLS_BROKEN
257
    if(!show_bits_long(gb, 32))return -1;
258
#endif
259
    ret = get_ur_golomb_jpegls(gb, k, state->limit - limit_add - 1, state->qbpp);
260

    
261
    /* decode mapped error */
262
    map = 0;
263
    if(!k && (RItype || ret) && (2 * state->B[Q] < state->N[Q]))
264
        map = 1;
265
    ret += RItype + map;
266

    
267
    if(ret & 1){
268
        ret = map - ((ret + 1) >> 1);
269
        state->B[Q]++;
270
    } else {
271
        ret = ret >> 1;
272
    }
273

    
274
    /* update state */
275
    state->A[Q] += ABS(ret) - RItype;
276
    ret *= state->twonear;
277
    if(state->N[Q] == state->reset){
278
        state->A[Q] >>=1;
279
        state->B[Q] >>=1;
280
        state->N[Q] >>=1;
281
    }
282
    state->N[Q]++;
283

    
284
    return ret;
285
}
286

    
287
/**
288
 * Decode one line of image
289
 */
290
static inline void ls_decode_line(JLSState *state, MJpegDecodeContext *s, uint8_t *last, uint8_t *dst, int last2, int w, int stride, int comp){
291
    int i, x = 0;
292
    int Ra, Rb, Rc, Rd;
293
    int D0, D1, D2;
294

    
295
    while(x < w) {
296
        int err, pred;
297

    
298
        /* compute gradients */
299
        Ra = x ? dst[x - stride] : last[x];
300
        Rb = last[x];
301
        Rc = x ? last[x - stride] : last2;
302
        Rd = (x >= w - stride) ? last[x] : last[x + stride];
303
        D0 = Rd - Rb;
304
        D1 = Rb - Rc;
305
        D2 = Rc - Ra;
306
        /* run mode */
307
        if((ABS(D0) <= state->near) && (ABS(D1) <= state->near) && (ABS(D2) <= state->near)) {
308
            int r;
309
            int RItype;
310

    
311
            /* decode full runs while available */
312
            while(get_bits1(&s->gb)) {
313
                int r;
314
                r = 1 << log2_run[state->run_index[comp]];
315
                if(x + r * stride > w) {
316
                    r = (w - x) / stride;
317
                }
318
                for(i = 0; i < r; i++) {
319
                    dst[x] = Ra;
320
                    x += stride;
321
                }
322
                /* if EOL reached, we stop decoding */
323
                if(r != (1 << log2_run[state->run_index[comp]]))
324
                    return;
325
                if(state->run_index[comp] < 31)
326
                    state->run_index[comp]++;
327
                if(x + stride > w)
328
                    return;
329
            }
330
            /* decode aborted run */
331
            r = log2_run[state->run_index[comp]];
332
            if(r)
333
                r = get_bits_long(&s->gb, r);
334
            for(i = 0; i < r; i++) {
335
                dst[x] = Ra;
336
                x += stride;
337
            }
338

    
339
            /* decode run termination value */
340
            Rb = last[x];
341
            RItype = (ABS(Ra - Rb) <= state->near) ? 1 : 0;
342
            err = ls_get_code_runterm(&s->gb, state, RItype, log2_run[state->run_index[comp]]);
343
            if(state->run_index[comp])
344
                state->run_index[comp]--;
345

    
346
            if(state->near && RItype){
347
                pred = Ra + err;
348
            } else {
349
                if(Rb < Ra)
350
                    pred = Rb - err;
351
                else
352
                    pred = Rb + err;
353
            }
354

    
355
            if(state->near){
356
                if(pred < -state->near)
357
                    pred += state->range * state->twonear;
358
                else if(pred > state->maxval + state->near)
359
                    pred -= state->range * state->twonear;
360
                pred = clip(pred, 0, state->maxval);
361
            }
362

    
363
            dst[x] = pred;
364
            x += stride;
365
        } else { /* regular mode */
366
            int context, sign;
367

    
368
            context = quantize(state, D0) * 81 + quantize(state, D1) * 9 + quantize(state, D2);
369
            pred = mid_pred(Ra, Ra + Rb - Rc, Rb);
370

    
371
            if(context < 0){
372
                context = -context;
373
                sign = 1;
374
            }else{
375
                sign = 0;
376
            }
377

    
378
            if(sign){
379
                pred = clip(pred - state->C[context], 0, state->maxval);
380
                err = -ls_get_code_regular(&s->gb, state, context);
381
            } else {
382
                pred = clip(pred + state->C[context], 0, state->maxval);
383
                err = ls_get_code_regular(&s->gb, state, context);
384
            }
385

    
386
            /* we have to do something more for near-lossless coding */
387
            pred += err;
388
            if(state->near) {
389
                if(pred < -state->near)
390
                    pred += state->range * state->twonear;
391
                else if(pred > state->maxval + state->near)
392
                    pred -= state->range * state->twonear;
393
                pred = clip(pred, 0, state->maxval);
394
            }
395

    
396
            dst[x] = pred;
397
            x += stride;
398
        }
399
    }
400
}
401

    
402
static int ls_decode_picture(MJpegDecodeContext *s, int near, int point_transform, int ilv){
403
    int i, t = 0;
404
    uint8_t *zero, *last, *cur;
405
    JLSState *state;
406
    int off, stride, width;
407

    
408
    zero = av_mallocz(s->picture.linesize[0]);
409
    last = zero;
410
    cur = s->picture.data[0];
411

    
412
    state = av_mallocz(sizeof(JLSState));
413
    /* initialize JPEG-LS state from JPEG parameters */
414
    state->near = near;
415
    state->bpp = (s->bits < 2) ? 2 : s->bits;
416
    state->maxval = s->maxval;
417
    state->T1 = s->t1;
418
    state->T2 = s->t2;
419
    state->T3 = s->t3;
420
    state->reset = s->reset;
421
    reset_ls_coding_parameters(state, 0);
422
    ls_init_state(state);
423

    
424
//    av_log(s->avctx, AV_LOG_DEBUG, "JPEG-LS params: %ix%i NEAR=%i MV=%i T(%i,%i,%i) RESET=%i, LIMIT=%i, qbpp=%i, RANGE=%i\n",s->width,s->height,state->near,state->maxval,state->T1,state->T2,state->T3,state->reset,state->limit,state->qbpp, state->range);
425
//    av_log(s->avctx, AV_LOG_DEBUG, "JPEG params: ILV=%i Pt=%i BPP=%i, scan = %i\n", ilv, point_transform, s->bits, s->cur_scan);
426
    if(ilv == 0) { /* separate planes */
427
        off = s->cur_scan - 1;
428
        stride = (s->nb_components > 1) ? 3 : 1;
429
        width = s->width * stride;
430
        cur += off;
431
        for(i = 0; i < s->height; i++) {
432
            ls_decode_line(state, s, last, cur, t, width, stride, off);
433
            t = last[0];
434
            last = cur;
435
            cur += s->picture.linesize[0];
436

    
437
            if (s->restart_interval && !--s->restart_count) {
438
                align_get_bits(&s->gb);
439
                skip_bits(&s->gb, 16); /* skip RSTn */
440
            }
441
        }
442
    } else if(ilv == 1) { /* line interleaving */
443
        int j;
444
        int Rc[3] = {0, 0, 0};
445
        memset(cur, 0, s->picture.linesize[0]);
446
        width = s->width * 3;
447
        for(i = 0; i < s->height; i++) {
448
            for(j = 0; j < 3; j++) {
449
                ls_decode_line(state, s, last + j, cur + j, Rc[j], width, 3, j);
450
                Rc[j] = last[j];
451

    
452
                if (s->restart_interval && !--s->restart_count) {
453
                    align_get_bits(&s->gb);
454
                    skip_bits(&s->gb, 16); /* skip RSTn */
455
                }
456
            }
457
            last = cur;
458
            cur += s->picture.linesize[0];
459
        }
460
    } else if(ilv == 2) { /* sample interleaving */
461
        av_log(s->avctx, AV_LOG_ERROR, "Sample interleaved images are not supported.\n");
462
        return -1;
463
    }
464

    
465
    av_free(state);
466
    av_free(zero);
467

    
468
    return 0;
469
}
470

    
471
#if defined(CONFIG_ENCODERS) && defined(CONFIG_JPEGLS_ENCODER)
472
/********** Encoder-specific functions **********/
473

    
474
/**
475
 * Encode error from regular symbol
476
 */
477
static inline void ls_encode_regular(JLSState *state, PutBitContext *pb, int Q, int err){
478
    int k;
479
    int val;
480
    int map;
481

    
482
    for(k = 0; (state->N[Q] << k) < state->A[Q]; k++);
483

    
484
    map = !state->near && !k && (2 * state->B[Q] <= -state->N[Q]);
485

    
486
    if(err < 0)
487
        err += state->range;
488
    if(err >= ((state->range + 1) >> 1)) {
489
        err -= state->range;
490
        val = 2 * ABS(err) - 1 - map;
491
    } else
492
        val = 2 * err + map;
493

    
494
    set_ur_golomb_jpegls(pb, val, k, state->limit, state->qbpp);
495

    
496
    state->A[Q] += ABS(err);
497
    state->B[Q] += err * state->twonear;
498

    
499
    if(state->N[Q] == state->reset) {
500
        state->A[Q] >>= 1;
501
        state->B[Q] >>= 1;
502
        state->N[Q] >>= 1;
503
    }
504
    state->N[Q]++;
505

    
506
    if(state->B[Q] <= -state->N[Q]) {
507
        state->B[Q] += state->N[Q];
508
        if(state->C[Q] > -128)
509
            state->C[Q]--;
510
        if(state->B[Q] <= -state->N[Q])
511
            state->B[Q] = -state->N[Q] + 1;
512
    }else if(state->B[Q] > 0){
513
        state->B[Q] -= state->N[Q];
514
        if(state->C[Q] < 127)
515
            state->C[Q]++;
516
        if(state->B[Q] > 0)
517
            state->B[Q] = 0;
518
    }
519
}
520

    
521
/**
522
 * Encode error from run termination
523
 */
524
static inline void ls_encode_runterm(JLSState *state, PutBitContext *pb, int RItype, int err, int limit_add){
525
    int k;
526
    int val, map;
527
    int Q = 365 + RItype;
528
    int temp;
529

    
530
    temp = state->A[Q];
531
    if(RItype)
532
        temp += state->N[Q] >> 1;
533
    for(k = 0; (state->N[Q] << k) < temp; k++);
534
    map = 0;
535
    if(!k && err && (2 * state->B[Q] < state->N[Q]))
536
        map = 1;
537

    
538
    if(err < 0)
539
        val = - (2 * err) - 1 - RItype + map;
540
    else
541
        val = 2 * err - RItype - map;
542
    set_ur_golomb_jpegls(pb, val, k, state->limit - limit_add - 1, state->qbpp);
543

    
544
    if(err < 0)
545
        state->B[Q]++;
546
    state->A[Q] += (val + 1 - RItype) >> 1;
547

    
548
    if(state->N[Q] == state->reset) {
549
        state->A[Q] >>= 1;
550
        state->B[Q] >>= 1;
551
        state->N[Q] >>= 1;
552
    }
553
    state->N[Q]++;
554
}
555

    
556
/**
557
 * Encode run value as specified by JPEG-LS standard
558
 */
559
static inline void ls_encode_run(JLSState *state, PutBitContext *pb, int run, int comp, int trail){
560
    while(run >= (1 << log2_run[state->run_index[comp]])){
561
        put_bits(pb, 1, 1);
562
        run -= 1 << log2_run[state->run_index[comp]];
563
        if(state->run_index[comp] < 31)
564
            state->run_index[comp]++;
565
    }
566
    /* if hit EOL, encode another full run, else encode aborted run */
567
    if(!trail && run) {
568
        put_bits(pb, 1, 1);
569
    }else if(trail){
570
        put_bits(pb, 1, 0);
571
        if(log2_run[state->run_index[comp]])
572
            put_bits(pb, log2_run[state->run_index[comp]], run);
573
    }
574
}
575

    
576
/**
577
 * Encode one line of image
578
 */
579
static inline void ls_encode_line(JLSState *state, PutBitContext *pb, uint8_t *last, uint8_t *cur, int last2, int w, int stride, int comp){
580
    int x = 0;
581
    int Ra, Rb, Rc, Rd;
582
    int D0, D1, D2;
583

    
584
    while(x < w) {
585
        int err, pred, sign;
586

    
587
        /* compute gradients */
588
        Ra = x ? cur[x - stride] : last[x];
589
        Rb = last[x];
590
        Rc = x ? last[x - stride] : last2;
591
        Rd = (x >= w - stride) ? last[x] : last[x + stride];
592
        D0 = Rd - Rb;
593
        D1 = Rb - Rc;
594
        D2 = Rc - Ra;
595

    
596
        /* run mode */
597
        if((ABS(D0) <= state->near) && (ABS(D1) <= state->near) && (ABS(D2) <= state->near)) {
598
            int RUNval, RItype, run;
599

    
600
            run = 0;
601
            RUNval = Ra;
602
            while(x < w && (ABS(cur[x] - RUNval) <= state->near)){
603
                run++;
604
                cur[x] = Ra;
605
                x += stride;
606
            }
607
            ls_encode_run(state, pb, run, comp, x < w);
608
            if(x >= w)
609
                return;
610
            Rb = last[x];
611
            RItype = (ABS(Ra - Rb) <= state->near);
612
            pred = RItype ? Ra : Rb;
613
            err = cur[x] - pred;
614

    
615
            if(!RItype && Ra > Rb)
616
                err = -err;
617

    
618
            if(state->near){
619
                if(err > 0)
620
                    err = (state->near + err) / state->twonear;
621
                else
622
                    err = -(state->near - err) / state->twonear;
623

    
624
                if(RItype || (Rb >= Ra))
625
                    Ra = clip(pred + err * state->twonear, 0, state->maxval);
626
                else
627
                    Ra = clip(pred - err * state->twonear, 0, state->maxval);
628
                cur[x] = Ra;
629
            }
630
            if(err < 0)
631
                err += state->range;
632
            if(err >= ((state->range + 1) >> 1))
633
                err -= state->range;
634

    
635
            ls_encode_runterm(state, pb, RItype, err, log2_run[state->run_index[comp]]);
636

    
637
            if(state->run_index[comp] > 0)
638
                state->run_index[comp]--;
639
            x += stride;
640
        } else { /* regular mode */
641
            int context;
642

    
643
            context = quantize(state, D0) * 81 + quantize(state, D1) * 9 + quantize(state, D2);
644
            pred = mid_pred(Ra, Ra + Rb - Rc, Rb);
645

    
646
            if(context < 0){
647
                context = -context;
648
                sign = 1;
649
                pred = clip(pred - state->C[context], 0, state->maxval);
650
                err = pred - cur[x];
651
            }else{
652
                sign = 0;
653
                pred = clip(pred + state->C[context], 0, state->maxval);
654
                err = cur[x] - pred;
655
            }
656

    
657
            if(state->near){
658
                if(err > 0)
659
                    err = (state->near + err) / state->twonear;
660
                else
661
                    err = -(state->near - err) / state->twonear;
662
                if(!sign)
663
                    Ra = clip(pred + err * state->twonear, 0, state->maxval);
664
                else
665
                    Ra = clip(pred - err * state->twonear, 0, state->maxval);
666
                cur[x] = Ra;
667
            }
668

    
669
            ls_encode_regular(state, pb, context, err);
670
            x += stride;
671
        }
672
    }
673
}
674

    
675
static void ls_store_lse(JLSState *state, PutBitContext *pb){
676
    /* Test if we have default params and don't need to store LSE */
677
    JLSState state2;
678
    memset(&state2, 0, sizeof(JLSState));
679
    state2.bpp = 8;
680
    state2.near = state->near;
681
    reset_ls_coding_parameters(&state2, 1);
682
    if(state->T1 == state2.T1 && state->T2 == state2.T2 && state->T3 == state2.T3 && state->reset == state2.reset)
683
        return;
684
    /* store LSE type 1 */
685
    put_marker(pb, LSE);
686
    put_bits(pb, 16, 13);
687
    put_bits(pb, 8,   1);
688
    put_bits(pb, 16, state->maxval);
689
    put_bits(pb, 16, state->T1);
690
    put_bits(pb, 16, state->T2);
691
    put_bits(pb, 16, state->T3);
692
    put_bits(pb, 16, state->reset);
693
}
694

    
695
static int encode_picture_ls(AVCodecContext *avctx, unsigned char *buf, int buf_size, void *data){
696
    JpeglsContext * const s = avctx->priv_data;
697
    AVFrame *pict = data;
698
    AVFrame * const p= (AVFrame*)&s->picture;
699
    const int near = avctx->prediction_method;
700
    PutBitContext pb, pb2;
701
    GetBitContext gb;
702
    uint8_t *buf2, *zero, *cur, *last;
703
    JLSState *state;
704
    int i, size;
705
    int comps;
706

    
707
    buf2 = av_malloc(buf_size);
708

    
709
    init_put_bits(&pb, buf, buf_size);
710
    init_put_bits(&pb2, buf2, buf_size);
711

    
712
    *p = *pict;
713
    p->pict_type= FF_I_TYPE;
714
    p->key_frame= 1;
715

    
716
    comps = (avctx->pix_fmt == PIX_FMT_GRAY8) ? 1 : 3;
717

    
718
    /* write our own JPEG header, can't use mjpeg_picture_header */
719
    put_marker(&pb, SOI);
720
    put_marker(&pb, SOF48);
721
    put_bits(&pb, 16, 8 + comps * 3); // header size depends on components
722
    put_bits(&pb,  8, 8);             // bpp
723
    put_bits(&pb, 16, avctx->height);
724
    put_bits(&pb, 16, avctx->width);
725
    put_bits(&pb,  8, comps);         // components
726
    for(i = 1; i <= comps; i++) {
727
        put_bits(&pb,  8, i);    // component ID
728
        put_bits(&pb,  8, 0x11); // subsampling: none
729
        put_bits(&pb,  8, 0);    // Tiq, used by JPEG-LS ext
730
    }
731

    
732
    put_marker(&pb, SOS);
733
    put_bits(&pb, 16, 6 + comps * 2);
734
    put_bits(&pb,  8, comps);
735
    for(i = 1; i <= comps; i++) {
736
        put_bits(&pb,  8, i);  // component ID
737
        put_bits(&pb,  8, 0);  // mapping index: none
738
    }
739
    put_bits(&pb,  8, near);
740
    put_bits(&pb,  8, (comps > 1) ? 1 : 0); // interleaving: 0 - plane, 1 - line
741
    put_bits(&pb,  8, 0); // point transform: none
742

    
743
    state = av_mallocz(sizeof(JLSState));
744
    /* initialize JPEG-LS state from JPEG parameters */
745
    state->near = near;
746
    state->bpp = 8;
747
    reset_ls_coding_parameters(state, 0);
748
    ls_init_state(state);
749

    
750
    ls_store_lse(state, &pb);
751

    
752
    zero = av_mallocz(p->linesize[0]);
753
    last = zero;
754
    cur = p->data[0];
755
    if(avctx->pix_fmt == PIX_FMT_GRAY8){
756
        int t = 0;
757

    
758
        for(i = 0; i < avctx->height; i++) {
759
            ls_encode_line(state, &pb2, last, cur, t, avctx->width, 1, 0);
760
            t = last[0];
761
            last = cur;
762
            cur += p->linesize[0];
763
        }
764
    }else if(avctx->pix_fmt == PIX_FMT_RGB24){
765
        int j, width;
766
        int Rc[3] = {0, 0, 0};
767

    
768
        width = avctx->width * 3;
769
        for(i = 0; i < avctx->height; i++) {
770
            for(j = 0; j < 3; j++) {
771
                ls_encode_line(state, &pb2, last + j, cur + j, Rc[j], width, 3, j);
772
                Rc[j] = last[j];
773
            }
774
            last = cur;
775
            cur += s->picture.linesize[0];
776
        }
777
    }else if(avctx->pix_fmt == PIX_FMT_BGR24){
778
        int j, width;
779
        int Rc[3] = {0, 0, 0};
780

    
781
        width = avctx->width * 3;
782
        for(i = 0; i < avctx->height; i++) {
783
            for(j = 2; j >= 0; j--) {
784
                ls_encode_line(state, &pb2, last + j, cur + j, Rc[j], width, 3, j);
785
                Rc[j] = last[j];
786
            }
787
            last = cur;
788
            cur += s->picture.linesize[0];
789
        }
790
    }
791

    
792
    av_free(zero);
793
    av_free(state);
794

    
795
    flush_put_bits(&pb2);
796
    /* do escape coding */
797
    size = put_bits_count(&pb2) >> 3;
798
    init_get_bits(&gb, buf2, size);
799
    while(get_bits_count(&gb) < size * 8){
800
        int v;
801
        v = get_bits(&gb, 8);
802
        put_bits(&pb, 8, v);
803
        if(v == 0xFF){
804
            v = get_bits(&gb, 7);
805
            put_bits(&pb, 8, v);
806
        }
807
    }
808
    align_put_bits(&pb);
809
    av_free(buf2);
810

    
811
    /* End of image */
812
    put_marker(&pb, EOI);
813
    flush_put_bits(&pb);
814

    
815
    emms_c();
816

    
817
    return put_bits_count(&pb) >> 3;
818
}
819

    
820
static int encode_init_ls(AVCodecContext *ctx) {
821
    JpeglsContext *c = (JpeglsContext*)ctx->priv_data;
822

    
823
    c->avctx = ctx;
824
    ctx->coded_frame = &c->picture;
825

    
826
    if(ctx->pix_fmt != PIX_FMT_GRAY8 && ctx->pix_fmt != PIX_FMT_RGB24 && ctx->pix_fmt != PIX_FMT_BGR24){
827
        av_log(ctx, AV_LOG_ERROR, "Only grayscale and RGB24/BGR24 images are supported\n");
828
        return -1;
829
    }
830
    return 0;
831
}
832

    
833
AVCodec jpegls_encoder = { //FIXME avoid MPV_* lossless jpeg shouldnt need them
834
    "jpegls",
835
    CODEC_TYPE_VIDEO,
836
    CODEC_ID_JPEGLS,
837
    sizeof(JpeglsContext),
838
    encode_init_ls,
839
    encode_picture_ls,
840
    NULL,
841
    .pix_fmts= (enum PixelFormat[]){PIX_FMT_BGR24, PIX_FMT_RGB24, PIX_FMT_GRAY8, -1},
842
};
843
#endif