1/*
2 * DVB subtitle decoding for ffmpeg
3 * Copyright (c) 2005 Ian Caulfield
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg 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 * FFmpeg 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 FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21#include "avcodec.h"
22#include "dsputil.h"
23#include "get_bits.h"
24#include "colorspace.h"
25
26//#define DEBUG
27//#define DEBUG_PACKET_CONTENTS
28//#define DEBUG_SAVE_IMAGES
29
30#define DVBSUB_PAGE_SEGMENT     0x10
31#define DVBSUB_REGION_SEGMENT   0x11
32#define DVBSUB_CLUT_SEGMENT     0x12
33#define DVBSUB_OBJECT_SEGMENT   0x13
34#define DVBSUB_DISPLAY_SEGMENT  0x80
35
36#define cm (ff_cropTbl + MAX_NEG_CROP)
37
38#ifdef DEBUG_SAVE_IMAGES
39#undef fprintf
40#if 0
41static void png_save(const char *filename, uint8_t *bitmap, int w, int h,
42                     uint32_t *rgba_palette)
43{
44    int x, y, v;
45    FILE *f;
46    char fname[40], fname2[40];
47    char command[1024];
48
49    snprintf(fname, 40, "%s.ppm", filename);
50
51    f = fopen(fname, "w");
52    if (!f) {
53        perror(fname);
54        exit(1);
55    }
56    fprintf(f, "P6\n"
57            "%d %d\n"
58            "%d\n",
59            w, h, 255);
60    for(y = 0; y < h; y++) {
61        for(x = 0; x < w; x++) {
62            v = rgba_palette[bitmap[y * w + x]];
63            putc((v >> 16) & 0xff, f);
64            putc((v >> 8) & 0xff, f);
65            putc((v >> 0) & 0xff, f);
66        }
67    }
68    fclose(f);
69
70
71    snprintf(fname2, 40, "%s-a.pgm", filename);
72
73    f = fopen(fname2, "w");
74    if (!f) {
75        perror(fname2);
76        exit(1);
77    }
78    fprintf(f, "P5\n"
79            "%d %d\n"
80            "%d\n",
81            w, h, 255);
82    for(y = 0; y < h; y++) {
83        for(x = 0; x < w; x++) {
84            v = rgba_palette[bitmap[y * w + x]];
85            putc((v >> 24) & 0xff, f);
86        }
87    }
88    fclose(f);
89
90    snprintf(command, 1024, "pnmtopng -alpha %s %s > %s.png 2> /dev/null", fname2, fname, filename);
91    system(command);
92
93    snprintf(command, 1024, "rm %s %s", fname, fname2);
94    system(command);
95}
96#endif
97
98static void png_save2(const char *filename, uint32_t *bitmap, int w, int h)
99{
100    int x, y, v;
101    FILE *f;
102    char fname[40], fname2[40];
103    char command[1024];
104
105    snprintf(fname, sizeof(fname), "%s.ppm", filename);
106
107    f = fopen(fname, "w");
108    if (!f) {
109        perror(fname);
110        exit(1);
111    }
112    fprintf(f, "P6\n"
113            "%d %d\n"
114            "%d\n",
115            w, h, 255);
116    for(y = 0; y < h; y++) {
117        for(x = 0; x < w; x++) {
118            v = bitmap[y * w + x];
119            putc((v >> 16) & 0xff, f);
120            putc((v >> 8) & 0xff, f);
121            putc((v >> 0) & 0xff, f);
122        }
123    }
124    fclose(f);
125
126
127    snprintf(fname2, sizeof(fname2), "%s-a.pgm", filename);
128
129    f = fopen(fname2, "w");
130    if (!f) {
131        perror(fname2);
132        exit(1);
133    }
134    fprintf(f, "P5\n"
135            "%d %d\n"
136            "%d\n",
137            w, h, 255);
138    for(y = 0; y < h; y++) {
139        for(x = 0; x < w; x++) {
140            v = bitmap[y * w + x];
141            putc((v >> 24) & 0xff, f);
142        }
143    }
144    fclose(f);
145
146    snprintf(command, sizeof(command), "pnmtopng -alpha %s %s > %s.png 2> /dev/null", fname2, fname, filename);
147    system(command);
148
149    snprintf(command, sizeof(command), "rm %s %s", fname, fname2);
150    system(command);
151}
152#endif
153
154#define RGBA(r,g,b,a) (((a) << 24) | ((r) << 16) | ((g) << 8) | (b))
155
156typedef struct DVBSubCLUT {
157    int id;
158
159    uint32_t clut4[4];
160    uint32_t clut16[16];
161    uint32_t clut256[256];
162
163    struct DVBSubCLUT *next;
164} DVBSubCLUT;
165
166static DVBSubCLUT default_clut;
167
168typedef struct DVBSubObjectDisplay {
169    int object_id;
170    int region_id;
171
172    int x_pos;
173    int y_pos;
174
175    int fgcolor;
176    int bgcolor;
177
178    struct DVBSubObjectDisplay *region_list_next;
179    struct DVBSubObjectDisplay *object_list_next;
180} DVBSubObjectDisplay;
181
182typedef struct DVBSubObject {
183    int id;
184
185    int type;
186
187    DVBSubObjectDisplay *display_list;
188
189    struct DVBSubObject *next;
190} DVBSubObject;
191
192typedef struct DVBSubRegionDisplay {
193    int region_id;
194
195    int x_pos;
196    int y_pos;
197
198    struct DVBSubRegionDisplay *next;
199} DVBSubRegionDisplay;
200
201typedef struct DVBSubRegion {
202    int id;
203
204    int width;
205    int height;
206    int depth;
207
208    int clut;
209    int bgcolor;
210
211    uint8_t *pbuf;
212    int buf_size;
213
214    DVBSubObjectDisplay *display_list;
215
216    struct DVBSubRegion *next;
217} DVBSubRegion;
218
219typedef struct DVBSubContext {
220    int composition_id;
221    int ancillary_id;
222
223    int time_out;
224    DVBSubRegion *region_list;
225    DVBSubCLUT   *clut_list;
226    DVBSubObject *object_list;
227
228    int display_list_size;
229    DVBSubRegionDisplay *display_list;
230} DVBSubContext;
231
232
233static DVBSubObject* get_object(DVBSubContext *ctx, int object_id)
234{
235    DVBSubObject *ptr = ctx->object_list;
236
237    while (ptr && ptr->id != object_id) {
238        ptr = ptr->next;
239    }
240
241    return ptr;
242}
243
244static DVBSubCLUT* get_clut(DVBSubContext *ctx, int clut_id)
245{
246    DVBSubCLUT *ptr = ctx->clut_list;
247
248    while (ptr && ptr->id != clut_id) {
249        ptr = ptr->next;
250    }
251
252    return ptr;
253}
254
255static DVBSubRegion* get_region(DVBSubContext *ctx, int region_id)
256{
257    DVBSubRegion *ptr = ctx->region_list;
258
259    while (ptr && ptr->id != region_id) {
260        ptr = ptr->next;
261    }
262
263    return ptr;
264}
265
266static void delete_region_display_list(DVBSubContext *ctx, DVBSubRegion *region)
267{
268    DVBSubObject *object, *obj2, **obj2_ptr;
269    DVBSubObjectDisplay *display, *obj_disp, **obj_disp_ptr;
270
271    while (region->display_list) {
272        display = region->display_list;
273
274        object = get_object(ctx, display->object_id);
275
276        if (object) {
277            obj_disp_ptr = &object->display_list;
278            obj_disp = *obj_disp_ptr;
279
280            while (obj_disp && obj_disp != display) {
281                obj_disp_ptr = &obj_disp->object_list_next;
282                obj_disp = *obj_disp_ptr;
283            }
284
285            if (obj_disp) {
286                *obj_disp_ptr = obj_disp->object_list_next;
287
288                if (!object->display_list) {
289                    obj2_ptr = &ctx->object_list;
290                    obj2 = *obj2_ptr;
291
292                    while (obj2 != object) {
293                        assert(obj2);
294                        obj2_ptr = &obj2->next;
295                        obj2 = *obj2_ptr;
296                    }
297
298                    *obj2_ptr = obj2->next;
299
300                    av_free(obj2);
301                }
302            }
303        }
304
305        region->display_list = display->region_list_next;
306
307        av_free(display);
308    }
309
310}
311
312static void delete_state(DVBSubContext *ctx)
313{
314    DVBSubRegion *region;
315    DVBSubCLUT *clut;
316
317    while (ctx->region_list) {
318        region = ctx->region_list;
319
320        ctx->region_list = region->next;
321
322        delete_region_display_list(ctx, region);
323        if (region->pbuf)
324            av_free(region->pbuf);
325
326        av_free(region);
327    }
328
329    while (ctx->clut_list) {
330        clut = ctx->clut_list;
331
332        ctx->clut_list = clut->next;
333
334        av_free(clut);
335    }
336
337    /* Should already be null */
338    if (ctx->object_list)
339        av_log(0, AV_LOG_ERROR, "Memory deallocation error!\n");
340}
341
342static av_cold int dvbsub_init_decoder(AVCodecContext *avctx)
343{
344    int i, r, g, b, a = 0;
345    DVBSubContext *ctx = (DVBSubContext*) avctx->priv_data;
346
347    memset(avctx->priv_data, 0, sizeof(DVBSubContext));
348
349    ctx->composition_id = avctx->sub_id & 0xffff;
350    ctx->ancillary_id = avctx->sub_id >> 16;
351
352    default_clut.id = -1;
353    default_clut.next = NULL;
354
355    default_clut.clut4[0] = RGBA(  0,   0,   0,   0);
356    default_clut.clut4[1] = RGBA(255, 255, 255, 255);
357    default_clut.clut4[2] = RGBA(  0,   0,   0, 255);
358    default_clut.clut4[3] = RGBA(127, 127, 127, 255);
359
360    default_clut.clut16[0] = RGBA(  0,   0,   0,   0);
361    for (i = 1; i < 16; i++) {
362        if (i < 8) {
363            r = (i & 1) ? 255 : 0;
364            g = (i & 2) ? 255 : 0;
365            b = (i & 4) ? 255 : 0;
366        } else {
367            r = (i & 1) ? 127 : 0;
368            g = (i & 2) ? 127 : 0;
369            b = (i & 4) ? 127 : 0;
370        }
371        default_clut.clut16[i] = RGBA(r, g, b, 255);
372    }
373
374    default_clut.clut256[0] = RGBA(  0,   0,   0,   0);
375    for (i = 1; i < 256; i++) {
376        if (i < 8) {
377            r = (i & 1) ? 255 : 0;
378            g = (i & 2) ? 255 : 0;
379            b = (i & 4) ? 255 : 0;
380            a = 63;
381        } else {
382            switch (i & 0x88) {
383            case 0x00:
384                r = ((i & 1) ? 85 : 0) + ((i & 0x10) ? 170 : 0);
385                g = ((i & 2) ? 85 : 0) + ((i & 0x20) ? 170 : 0);
386                b = ((i & 4) ? 85 : 0) + ((i & 0x40) ? 170 : 0);
387                a = 255;
388                break;
389            case 0x08:
390                r = ((i & 1) ? 85 : 0) + ((i & 0x10) ? 170 : 0);
391                g = ((i & 2) ? 85 : 0) + ((i & 0x20) ? 170 : 0);
392                b = ((i & 4) ? 85 : 0) + ((i & 0x40) ? 170 : 0);
393                a = 127;
394                break;
395            case 0x80:
396                r = 127 + ((i & 1) ? 43 : 0) + ((i & 0x10) ? 85 : 0);
397                g = 127 + ((i & 2) ? 43 : 0) + ((i & 0x20) ? 85 : 0);
398                b = 127 + ((i & 4) ? 43 : 0) + ((i & 0x40) ? 85 : 0);
399                a = 255;
400                break;
401            case 0x88:
402                r = ((i & 1) ? 43 : 0) + ((i & 0x10) ? 85 : 0);
403                g = ((i & 2) ? 43 : 0) + ((i & 0x20) ? 85 : 0);
404                b = ((i & 4) ? 43 : 0) + ((i & 0x40) ? 85 : 0);
405                a = 255;
406                break;
407            }
408        }
409        default_clut.clut256[i] = RGBA(r, g, b, a);
410    }
411
412    return 0;
413}
414
415static av_cold int dvbsub_close_decoder(AVCodecContext *avctx)
416{
417    DVBSubContext *ctx = (DVBSubContext*) avctx->priv_data;
418    DVBSubRegionDisplay *display;
419
420    delete_state(ctx);
421
422    while (ctx->display_list) {
423        display = ctx->display_list;
424        ctx->display_list = display->next;
425
426        av_free(display);
427    }
428
429    return 0;
430}
431
432static int dvbsub_read_2bit_string(uint8_t *destbuf, int dbuf_len,
433                                   const uint8_t **srcbuf, int buf_size,
434                                   int non_mod, uint8_t *map_table)
435{
436    GetBitContext gb;
437
438    int bits;
439    int run_length;
440    int pixels_read = 0;
441
442    init_get_bits(&gb, *srcbuf, buf_size << 3);
443
444    while (get_bits_count(&gb) < buf_size << 3 && pixels_read < dbuf_len) {
445        bits = get_bits(&gb, 2);
446
447        if (bits) {
448            if (non_mod != 1 || bits != 1) {
449                if (map_table)
450                    *destbuf++ = map_table[bits];
451                else
452                    *destbuf++ = bits;
453            }
454            pixels_read++;
455        } else {
456            bits = get_bits1(&gb);
457            if (bits == 1) {
458                run_length = get_bits(&gb, 3) + 3;
459                bits = get_bits(&gb, 2);
460
461                if (non_mod == 1 && bits == 1)
462                    pixels_read += run_length;
463                else {
464                    if (map_table)
465                        bits = map_table[bits];
466                    while (run_length-- > 0 && pixels_read < dbuf_len) {
467                        *destbuf++ = bits;
468                        pixels_read++;
469                    }
470                }
471            } else {
472                bits = get_bits1(&gb);
473                if (bits == 0) {
474                    bits = get_bits(&gb, 2);
475                    if (bits == 2) {
476                        run_length = get_bits(&gb, 4) + 12;
477                        bits = get_bits(&gb, 2);
478
479                        if (non_mod == 1 && bits == 1)
480                            pixels_read += run_length;
481                        else {
482                            if (map_table)
483                                bits = map_table[bits];
484                            while (run_length-- > 0 && pixels_read < dbuf_len) {
485                                *destbuf++ = bits;
486                                pixels_read++;
487                            }
488                        }
489                    } else if (bits == 3) {
490                        run_length = get_bits(&gb, 8) + 29;
491                        bits = get_bits(&gb, 2);
492
493                        if (non_mod == 1 && bits == 1)
494                            pixels_read += run_length;
495                        else {
496                            if (map_table)
497                                bits = map_table[bits];
498                            while (run_length-- > 0 && pixels_read < dbuf_len) {
499                                *destbuf++ = bits;
500                                pixels_read++;
501                            }
502                        }
503                    } else if (bits == 1) {
504                        pixels_read += 2;
505                        if (map_table)
506                            bits = map_table[0];
507                        else
508                            bits = 0;
509                        if (pixels_read <= dbuf_len) {
510                            *destbuf++ = bits;
511                            *destbuf++ = bits;
512                        }
513                    } else {
514                        (*srcbuf) += (get_bits_count(&gb) + 7) >> 3;
515                        return pixels_read;
516                    }
517                } else {
518                    if (map_table)
519                        bits = map_table[0];
520                    else
521                        bits = 0;
522                    *destbuf++ = bits;
523                    pixels_read++;
524                }
525            }
526        }
527    }
528
529    if (get_bits(&gb, 6))
530        av_log(0, AV_LOG_ERROR, "DVBSub error: line overflow\n");
531
532    (*srcbuf) += (get_bits_count(&gb) + 7) >> 3;
533
534    return pixels_read;
535}
536
537static int dvbsub_read_4bit_string(uint8_t *destbuf, int dbuf_len,
538                                   const uint8_t **srcbuf, int buf_size,
539                                   int non_mod, uint8_t *map_table)
540{
541    GetBitContext gb;
542
543    int bits;
544    int run_length;
545    int pixels_read = 0;
546
547    init_get_bits(&gb, *srcbuf, buf_size << 3);
548
549    while (get_bits_count(&gb) < buf_size << 3 && pixels_read < dbuf_len) {
550        bits = get_bits(&gb, 4);
551
552        if (bits) {
553            if (non_mod != 1 || bits != 1) {
554                if (map_table)
555                    *destbuf++ = map_table[bits];
556                else
557                    *destbuf++ = bits;
558            }
559            pixels_read++;
560        } else {
561            bits = get_bits1(&gb);
562            if (bits == 0) {
563                run_length = get_bits(&gb, 3);
564
565                if (run_length == 0) {
566                    (*srcbuf) += (get_bits_count(&gb) + 7) >> 3;
567                    return pixels_read;
568                }
569
570                run_length += 2;
571
572                if (map_table)
573                    bits = map_table[0];
574                else
575                    bits = 0;
576
577                while (run_length-- > 0 && pixels_read < dbuf_len) {
578                    *destbuf++ = bits;
579                    pixels_read++;
580                }
581            } else {
582                bits = get_bits1(&gb);
583                if (bits == 0) {
584                    run_length = get_bits(&gb, 2) + 4;
585                    bits = get_bits(&gb, 4);
586
587                    if (non_mod == 1 && bits == 1)
588                        pixels_read += run_length;
589                    else {
590                        if (map_table)
591                            bits = map_table[bits];
592                        while (run_length-- > 0 && pixels_read < dbuf_len) {
593                            *destbuf++ = bits;
594                            pixels_read++;
595                        }
596                    }
597                } else {
598                    bits = get_bits(&gb, 2);
599                    if (bits == 2) {
600                        run_length = get_bits(&gb, 4) + 9;
601                        bits = get_bits(&gb, 4);
602
603                        if (non_mod == 1 && bits == 1)
604                            pixels_read += run_length;
605                        else {
606                            if (map_table)
607                                bits = map_table[bits];
608                            while (run_length-- > 0 && pixels_read < dbuf_len) {
609                                *destbuf++ = bits;
610                                pixels_read++;
611                            }
612                        }
613                    } else if (bits == 3) {
614                        run_length = get_bits(&gb, 8) + 25;
615                        bits = get_bits(&gb, 4);
616
617                        if (non_mod == 1 && bits == 1)
618                            pixels_read += run_length;
619                        else {
620                            if (map_table)
621                                bits = map_table[bits];
622                            while (run_length-- > 0 && pixels_read < dbuf_len) {
623                                *destbuf++ = bits;
624                                pixels_read++;
625                            }
626                        }
627                    } else if (bits == 1) {
628                        pixels_read += 2;
629                        if (map_table)
630                            bits = map_table[0];
631                        else
632                            bits = 0;
633                        if (pixels_read <= dbuf_len) {
634                            *destbuf++ = bits;
635                            *destbuf++ = bits;
636                        }
637                    } else {
638                        if (map_table)
639                            bits = map_table[0];
640                        else
641                            bits = 0;
642                        *destbuf++ = bits;
643                        pixels_read ++;
644                    }
645                }
646            }
647        }
648    }
649
650    if (get_bits(&gb, 8))
651        av_log(0, AV_LOG_ERROR, "DVBSub error: line overflow\n");
652
653    (*srcbuf) += (get_bits_count(&gb) + 7) >> 3;
654
655    return pixels_read;
656}
657
658static int dvbsub_read_8bit_string(uint8_t *destbuf, int dbuf_len,
659                                    const uint8_t **srcbuf, int buf_size,
660                                    int non_mod, uint8_t *map_table)
661{
662    const uint8_t *sbuf_end = (*srcbuf) + buf_size;
663    int bits;
664    int run_length;
665    int pixels_read = 0;
666
667    while (*srcbuf < sbuf_end && pixels_read < dbuf_len) {
668        bits = *(*srcbuf)++;
669
670        if (bits) {
671            if (non_mod != 1 || bits != 1) {
672                if (map_table)
673                    *destbuf++ = map_table[bits];
674                else
675                    *destbuf++ = bits;
676            }
677            pixels_read++;
678        } else {
679            bits = *(*srcbuf)++;
680            run_length = bits & 0x7f;
681            if ((bits & 0x80) == 0) {
682                if (run_length == 0) {
683                    return pixels_read;
684                }
685
686                if (map_table)
687                    bits = map_table[0];
688                else
689                    bits = 0;
690                while (run_length-- > 0 && pixels_read < dbuf_len) {
691                    *destbuf++ = bits;
692                    pixels_read++;
693                }
694            } else {
695                bits = *(*srcbuf)++;
696
697                if (non_mod == 1 && bits == 1)
698                    pixels_read += run_length;
699                if (map_table)
700                    bits = map_table[bits];
701                else while (run_length-- > 0 && pixels_read < dbuf_len) {
702                    *destbuf++ = bits;
703                    pixels_read++;
704                }
705            }
706        }
707    }
708
709    if (*(*srcbuf)++)
710        av_log(0, AV_LOG_ERROR, "DVBSub error: line overflow\n");
711
712    return pixels_read;
713}
714
715
716
717static void dvbsub_parse_pixel_data_block(AVCodecContext *avctx, DVBSubObjectDisplay *display,
718                                          const uint8_t *buf, int buf_size, int top_bottom, int non_mod)
719{
720    DVBSubContext *ctx = (DVBSubContext*) avctx->priv_data;
721
722    DVBSubRegion *region = get_region(ctx, display->region_id);
723    const uint8_t *buf_end = buf + buf_size;
724    uint8_t *pbuf;
725    int x_pos, y_pos;
726    int i;
727
728    uint8_t map2to4[] = { 0x0,  0x7,  0x8,  0xf};
729    uint8_t map2to8[] = {0x00, 0x77, 0x88, 0xff};
730    uint8_t map4to8[] = {0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77,
731                         0x88, 0x99, 0xaa, 0xbb, 0xcc, 0xdd, 0xee, 0xff};
732    uint8_t *map_table;
733
734    dprintf(avctx, "DVB pixel block size %d, %s field:\n", buf_size,
735            top_bottom ? "bottom" : "top");
736
737#ifdef DEBUG_PACKET_CONTENTS
738    for (i = 0; i < buf_size; i++) {
739        if (i % 16 == 0)
740            av_log(avctx, AV_LOG_INFO, "0x%08p: ", buf+i);
741
742        av_log(avctx, AV_LOG_INFO, "%02x ", buf[i]);
743        if (i % 16 == 15)
744            av_log(avctx, AV_LOG_INFO, "\n");
745    }
746
747    if (i % 16)
748        av_log(avctx, AV_LOG_INFO, "\n");
749
750#endif
751
752    if (region == 0)
753        return;
754
755    pbuf = region->pbuf;
756
757    x_pos = display->x_pos;
758    y_pos = display->y_pos;
759
760    if ((y_pos & 1) != top_bottom)
761        y_pos++;
762
763    while (buf < buf_end) {
764        if (x_pos > region->width || y_pos > region->height) {
765            av_log(avctx, AV_LOG_ERROR, "Invalid object location!\n");
766            return;
767        }
768
769        switch (*buf++) {
770        case 0x10:
771            if (region->depth == 8)
772                map_table = map2to8;
773            else if (region->depth == 4)
774                map_table = map2to4;
775            else
776                map_table = NULL;
777
778            x_pos += dvbsub_read_2bit_string(pbuf + (y_pos * region->width) + x_pos,
779                                                region->width - x_pos, &buf, buf_size,
780                                                non_mod, map_table);
781            break;
782        case 0x11:
783            if (region->depth < 4) {
784                av_log(avctx, AV_LOG_ERROR, "4-bit pixel string in %d-bit region!\n", region->depth);
785                return;
786            }
787
788            if (region->depth == 8)
789                map_table = map4to8;
790            else
791                map_table = NULL;
792
793            x_pos += dvbsub_read_4bit_string(pbuf + (y_pos * region->width) + x_pos,
794                                                region->width - x_pos, &buf, buf_size,
795                                                non_mod, map_table);
796            break;
797        case 0x12:
798            if (region->depth < 8) {
799                av_log(avctx, AV_LOG_ERROR, "8-bit pixel string in %d-bit region!\n", region->depth);
800                return;
801            }
802
803            x_pos += dvbsub_read_8bit_string(pbuf + (y_pos * region->width) + x_pos,
804                                                region->width - x_pos, &buf, buf_size,
805                                                non_mod, NULL);
806            break;
807
808        case 0x20:
809            map2to4[0] = (*buf) >> 4;
810            map2to4[1] = (*buf++) & 0xf;
811            map2to4[2] = (*buf) >> 4;
812            map2to4[3] = (*buf++) & 0xf;
813            break;
814        case 0x21:
815            for (i = 0; i < 4; i++)
816                map2to8[i] = *buf++;
817            break;
818        case 0x22:
819            for (i = 0; i < 16; i++)
820                map4to8[i] = *buf++;
821            break;
822
823        case 0xf0:
824            x_pos = display->x_pos;
825            y_pos += 2;
826            break;
827        default:
828            av_log(avctx, AV_LOG_INFO, "Unknown/unsupported pixel block 0x%x\n", *(buf-1));
829        }
830    }
831
832}
833
834static void dvbsub_parse_object_segment(AVCodecContext *avctx,
835                                        const uint8_t *buf, int buf_size)
836{
837    DVBSubContext *ctx = (DVBSubContext*) avctx->priv_data;
838
839    const uint8_t *buf_end = buf + buf_size;
840    const uint8_t *block;
841    int object_id;
842    DVBSubObject *object;
843    DVBSubObjectDisplay *display;
844    int top_field_len, bottom_field_len;
845
846    int coding_method, non_modifying_color;
847
848    object_id = AV_RB16(buf);
849    buf += 2;
850
851    object = get_object(ctx, object_id);
852
853    if (!object)
854        return;
855
856    coding_method = ((*buf) >> 2) & 3;
857    non_modifying_color = ((*buf++) >> 1) & 1;
858
859    if (coding_method == 0) {
860        top_field_len = AV_RB16(buf);
861        buf += 2;
862        bottom_field_len = AV_RB16(buf);
863        buf += 2;
864
865        if (buf + top_field_len + bottom_field_len > buf_end) {
866            av_log(avctx, AV_LOG_ERROR, "Field data size too large\n");
867            return;
868        }
869
870        for (display = object->display_list; display; display = display->object_list_next) {
871            block = buf;
872
873            dvbsub_parse_pixel_data_block(avctx, display, block, top_field_len, 0,
874                                            non_modifying_color);
875
876            if (bottom_field_len > 0)
877                block = buf + top_field_len;
878            else
879                bottom_field_len = top_field_len;
880
881            dvbsub_parse_pixel_data_block(avctx, display, block, bottom_field_len, 1,
882                                            non_modifying_color);
883        }
884
885/*  } else if (coding_method == 1) {*/
886
887    } else {
888        av_log(avctx, AV_LOG_ERROR, "Unknown object coding %d\n", coding_method);
889    }
890
891}
892
893static void dvbsub_parse_clut_segment(AVCodecContext *avctx,
894                                        const uint8_t *buf, int buf_size)
895{
896    DVBSubContext *ctx = (DVBSubContext*) avctx->priv_data;
897
898    const uint8_t *buf_end = buf + buf_size;
899    int clut_id;
900    DVBSubCLUT *clut;
901    int entry_id, depth , full_range;
902    int y, cr, cb, alpha;
903    int r, g, b, r_add, g_add, b_add;
904
905#ifdef DEBUG_PACKET_CONTENTS
906    int i;
907
908    av_log(avctx, AV_LOG_INFO, "DVB clut packet:\n");
909
910    for (i=0; i < buf_size; i++) {
911        av_log(avctx, AV_LOG_INFO, "%02x ", buf[i]);
912        if (i % 16 == 15)
913            av_log(avctx, AV_LOG_INFO, "\n");
914    }
915
916    if (i % 16)
917        av_log(avctx, AV_LOG_INFO, "\n");
918
919#endif
920
921    clut_id = *buf++;
922    buf += 1;
923
924    clut = get_clut(ctx, clut_id);
925
926    if (!clut) {
927        clut = av_malloc(sizeof(DVBSubCLUT));
928
929        memcpy(clut, &default_clut, sizeof(DVBSubCLUT));
930
931        clut->id = clut_id;
932
933        clut->next = ctx->clut_list;
934        ctx->clut_list = clut;
935    }
936
937    while (buf + 4 < buf_end) {
938        entry_id = *buf++;
939
940        depth = (*buf) & 0xe0;
941
942        if (depth == 0) {
943            av_log(avctx, AV_LOG_ERROR, "Invalid clut depth 0x%x!\n", *buf);
944            return;
945        }
946
947        full_range = (*buf++) & 1;
948
949        if (full_range) {
950            y = *buf++;
951            cr = *buf++;
952            cb = *buf++;
953            alpha = *buf++;
954        } else {
955            y = buf[0] & 0xfc;
956            cr = (((buf[0] & 3) << 2) | ((buf[1] >> 6) & 3)) << 4;
957            cb = (buf[1] << 2) & 0xf0;
958            alpha = (buf[1] << 6) & 0xc0;
959
960            buf += 2;
961        }
962
963        if (y == 0)
964            alpha = 0xff;
965
966        YUV_TO_RGB1_CCIR(cb, cr);
967        YUV_TO_RGB2_CCIR(r, g, b, y);
968
969        dprintf(avctx, "clut %d := (%d,%d,%d,%d)\n", entry_id, r, g, b, alpha);
970
971        if (depth & 0x80)
972            clut->clut4[entry_id] = RGBA(r,g,b,255 - alpha);
973        if (depth & 0x40)
974            clut->clut16[entry_id] = RGBA(r,g,b,255 - alpha);
975        if (depth & 0x20)
976            clut->clut256[entry_id] = RGBA(r,g,b,255 - alpha);
977    }
978}
979
980
981static void dvbsub_parse_region_segment(AVCodecContext *avctx,
982                                        const uint8_t *buf, int buf_size)
983{
984    DVBSubContext *ctx = (DVBSubContext*) avctx->priv_data;
985
986    const uint8_t *buf_end = buf + buf_size;
987    int region_id, object_id;
988    DVBSubRegion *region;
989    DVBSubObject *object;
990    DVBSubObjectDisplay *display;
991    int fill;
992
993    if (buf_size < 10)
994        return;
995
996    region_id = *buf++;
997
998    region = get_region(ctx, region_id);
999
1000    if (!region) {
1001        region = av_mallocz(sizeof(DVBSubRegion));
1002
1003        region->id = region_id;
1004
1005        region->next = ctx->region_list;
1006        ctx->region_list = region;
1007    }
1008
1009    fill = ((*buf++) >> 3) & 1;
1010
1011    region->width = AV_RB16(buf);
1012    buf += 2;
1013    region->height = AV_RB16(buf);
1014    buf += 2;
1015
1016    if (region->width * region->height != region->buf_size) {
1017        if (region->pbuf)
1018            av_free(region->pbuf);
1019
1020        region->buf_size = region->width * region->height;
1021
1022        region->pbuf = av_malloc(region->buf_size);
1023
1024        fill = 1;
1025    }
1026
1027    region->depth = 1 << (((*buf++) >> 2) & 7);
1028    if(region->depth<2 || region->depth>8){
1029        av_log(avctx, AV_LOG_ERROR, "region depth %d is invalid\n", region->depth);
1030        region->depth= 4;
1031    }
1032    region->clut = *buf++;
1033
1034    if (region->depth == 8)
1035        region->bgcolor = *buf++;
1036    else {
1037        buf += 1;
1038
1039        if (region->depth == 4)
1040            region->bgcolor = (((*buf++) >> 4) & 15);
1041        else
1042            region->bgcolor = (((*buf++) >> 2) & 3);
1043    }
1044
1045    dprintf(avctx, "Region %d, (%dx%d)\n", region_id, region->width, region->height);
1046
1047    if (fill) {
1048        memset(region->pbuf, region->bgcolor, region->buf_size);
1049        dprintf(avctx, "Fill region (%d)\n", region->bgcolor);
1050    }
1051
1052    delete_region_display_list(ctx, region);
1053
1054    while (buf + 5 < buf_end) {
1055        object_id = AV_RB16(buf);
1056        buf += 2;
1057
1058        object = get_object(ctx, object_id);
1059
1060        if (!object) {
1061            object = av_mallocz(sizeof(DVBSubObject));
1062
1063            object->id = object_id;
1064            object->next = ctx->object_list;
1065            ctx->object_list = object;
1066        }
1067
1068        object->type = (*buf) >> 6;
1069
1070        display = av_mallocz(sizeof(DVBSubObjectDisplay));
1071
1072        display->object_id = object_id;
1073        display->region_id = region_id;
1074
1075        display->x_pos = AV_RB16(buf) & 0xfff;
1076        buf += 2;
1077        display->y_pos = AV_RB16(buf) & 0xfff;
1078        buf += 2;
1079
1080        if ((object->type == 1 || object->type == 2) && buf+1 < buf_end) {
1081            display->fgcolor = *buf++;
1082            display->bgcolor = *buf++;
1083        }
1084
1085        display->region_list_next = region->display_list;
1086        region->display_list = display;
1087
1088        display->object_list_next = object->display_list;
1089        object->display_list = display;
1090    }
1091}
1092
1093static void dvbsub_parse_page_segment(AVCodecContext *avctx,
1094                                        const uint8_t *buf, int buf_size)
1095{
1096    DVBSubContext *ctx = (DVBSubContext*) avctx->priv_data;
1097    DVBSubRegionDisplay *display;
1098    DVBSubRegionDisplay *tmp_display_list, **tmp_ptr;
1099
1100    const uint8_t *buf_end = buf + buf_size;
1101    int region_id;
1102    int page_state;
1103
1104    if (buf_size < 1)
1105        return;
1106
1107    ctx->time_out = *buf++;
1108    page_state = ((*buf++) >> 2) & 3;
1109
1110    dprintf(avctx, "Page time out %ds, state %d\n", ctx->time_out, page_state);
1111
1112    if (page_state == 2) {
1113        delete_state(ctx);
1114    }
1115
1116    tmp_display_list = ctx->display_list;
1117    ctx->display_list = NULL;
1118    ctx->display_list_size = 0;
1119
1120    while (buf + 5 < buf_end) {
1121        region_id = *buf++;
1122        buf += 1;
1123
1124        display = tmp_display_list;
1125        tmp_ptr = &tmp_display_list;
1126
1127        while (display && display->region_id != region_id) {
1128            tmp_ptr = &display->next;
1129            display = display->next;
1130        }
1131
1132        if (!display)
1133            display = av_mallocz(sizeof(DVBSubRegionDisplay));
1134
1135        display->region_id = region_id;
1136
1137        display->x_pos = AV_RB16(buf);
1138        buf += 2;
1139        display->y_pos = AV_RB16(buf);
1140        buf += 2;
1141
1142        *tmp_ptr = display->next;
1143
1144        display->next = ctx->display_list;
1145        ctx->display_list = display;
1146        ctx->display_list_size++;
1147
1148        dprintf(avctx, "Region %d, (%d,%d)\n", region_id, display->x_pos, display->y_pos);
1149    }
1150
1151    while (tmp_display_list) {
1152        display = tmp_display_list;
1153
1154        tmp_display_list = display->next;
1155
1156        av_free(display);
1157    }
1158
1159}
1160
1161
1162#ifdef DEBUG_SAVE_IMAGES
1163static void save_display_set(DVBSubContext *ctx)
1164{
1165    DVBSubRegion *region;
1166    DVBSubRegionDisplay *display;
1167    DVBSubCLUT *clut;
1168    uint32_t *clut_table;
1169    int x_pos, y_pos, width, height;
1170    int x, y, y_off, x_off;
1171    uint32_t *pbuf;
1172    char filename[32];
1173    static int fileno_index = 0;
1174
1175    x_pos = -1;
1176    y_pos = -1;
1177    width = 0;
1178    height = 0;
1179
1180    for (display = ctx->display_list; display; display = display->next) {
1181        region = get_region(ctx, display->region_id);
1182
1183        if (x_pos == -1) {
1184            x_pos = display->x_pos;
1185            y_pos = display->y_pos;
1186            width = region->width;
1187            height = region->height;
1188        } else {
1189            if (display->x_pos < x_pos) {
1190                width += (x_pos - display->x_pos);
1191                x_pos = display->x_pos;
1192            }
1193
1194            if (display->y_pos < y_pos) {
1195                height += (y_pos - display->y_pos);
1196                y_pos = display->y_pos;
1197            }
1198
1199            if (display->x_pos + region->width > x_pos + width) {
1200                width = display->x_pos + region->width - x_pos;
1201            }
1202
1203            if (display->y_pos + region->height > y_pos + height) {
1204                height = display->y_pos + region->height - y_pos;
1205            }
1206        }
1207    }
1208
1209    if (x_pos >= 0) {
1210
1211        pbuf = av_malloc(width * height * 4);
1212
1213        for (display = ctx->display_list; display; display = display->next) {
1214            region = get_region(ctx, display->region_id);
1215
1216            x_off = display->x_pos - x_pos;
1217            y_off = display->y_pos - y_pos;
1218
1219            clut = get_clut(ctx, region->clut);
1220
1221            if (clut == 0)
1222                clut = &default_clut;
1223
1224            switch (region->depth) {
1225            case 2:
1226                clut_table = clut->clut4;
1227                break;
1228            case 8:
1229                clut_table = clut->clut256;
1230                break;
1231            case 4:
1232            default:
1233                clut_table = clut->clut16;
1234                break;
1235            }
1236
1237            for (y = 0; y < region->height; y++) {
1238                for (x = 0; x < region->width; x++) {
1239                    pbuf[((y + y_off) * width) + x_off + x] =
1240                        clut_table[region->pbuf[y * region->width + x]];
1241                }
1242            }
1243
1244        }
1245
1246        snprintf(filename, sizeof(filename), "dvbs.%d", fileno_index);
1247
1248        png_save2(filename, pbuf, width, height);
1249
1250        av_free(pbuf);
1251    }
1252
1253    fileno_index++;
1254}
1255#endif
1256
1257static int dvbsub_display_end_segment(AVCodecContext *avctx, const uint8_t *buf,
1258                                        int buf_size, AVSubtitle *sub)
1259{
1260    DVBSubContext *ctx = (DVBSubContext*) avctx->priv_data;
1261
1262    DVBSubRegion *region;
1263    DVBSubRegionDisplay *display;
1264    AVSubtitleRect *rect;
1265    DVBSubCLUT *clut;
1266    uint32_t *clut_table;
1267    int i;
1268
1269    sub->rects = NULL;
1270    sub->start_display_time = 0;
1271    sub->end_display_time = ctx->time_out * 1000;
1272    sub->format = 0;
1273
1274    sub->num_rects = ctx->display_list_size;
1275
1276    if (sub->num_rects > 0){
1277        sub->rects = av_mallocz(sizeof(*sub->rects) * sub->num_rects);
1278        for(i=0; i<sub->num_rects; i++)
1279            sub->rects[i] = av_mallocz(sizeof(*sub->rects[i]));
1280    }
1281
1282    i = 0;
1283
1284    for (display = ctx->display_list; display; display = display->next) {
1285        region = get_region(ctx, display->region_id);
1286        rect = sub->rects[i];
1287
1288        if (!region)
1289            continue;
1290
1291        rect->x = display->x_pos;
1292        rect->y = display->y_pos;
1293        rect->w = region->width;
1294        rect->h = region->height;
1295        rect->nb_colors = 16;
1296        rect->type      = SUBTITLE_BITMAP;
1297        rect->pict.linesize[0] = region->width;
1298
1299        clut = get_clut(ctx, region->clut);
1300
1301        if (!clut)
1302            clut = &default_clut;
1303
1304        switch (region->depth) {
1305        case 2:
1306            clut_table = clut->clut4;
1307            break;
1308        case 8:
1309            clut_table = clut->clut256;
1310            break;
1311        case 4:
1312        default:
1313            clut_table = clut->clut16;
1314            break;
1315        }
1316
1317        rect->pict.data[1] = av_mallocz(AVPALETTE_SIZE);
1318        memcpy(rect->pict.data[1], clut_table, (1 << region->depth) * sizeof(uint32_t));
1319
1320        rect->pict.data[0] = av_malloc(region->buf_size);
1321        memcpy(rect->pict.data[0], region->pbuf, region->buf_size);
1322
1323        i++;
1324    }
1325
1326    sub->num_rects = i;
1327
1328#ifdef DEBUG_SAVE_IMAGES
1329    save_display_set(ctx);
1330#endif
1331
1332    return 1;
1333}
1334
1335static int dvbsub_decode(AVCodecContext *avctx,
1336                         void *data, int *data_size,
1337                         AVPacket *avpkt)
1338{
1339    const uint8_t *buf = avpkt->data;
1340    int buf_size = avpkt->size;
1341    DVBSubContext *ctx = (DVBSubContext*) avctx->priv_data;
1342    AVSubtitle *sub = (AVSubtitle*) data;
1343    const uint8_t *p, *p_end;
1344    int segment_type;
1345    int page_id;
1346    int segment_length;
1347
1348#ifdef DEBUG_PACKET_CONTENTS
1349    int i;
1350
1351    av_log(avctx, AV_LOG_INFO, "DVB sub packet:\n");
1352
1353    for (i=0; i < buf_size; i++) {
1354        av_log(avctx, AV_LOG_INFO, "%02x ", buf[i]);
1355        if (i % 16 == 15)
1356            av_log(avctx, AV_LOG_INFO, "\n");
1357    }
1358
1359    if (i % 16)
1360        av_log(avctx, AV_LOG_INFO, "\n");
1361
1362#endif
1363
1364    if (buf_size <= 2)
1365        return -1;
1366
1367    p = buf;
1368    p_end = buf + buf_size;
1369
1370    while (p < p_end && *p == 0x0f) {
1371        p += 1;
1372        segment_type = *p++;
1373        page_id = AV_RB16(p);
1374        p += 2;
1375        segment_length = AV_RB16(p);
1376        p += 2;
1377
1378        if (page_id == ctx->composition_id || page_id == ctx->ancillary_id) {
1379            switch (segment_type) {
1380            case DVBSUB_PAGE_SEGMENT:
1381                dvbsub_parse_page_segment(avctx, p, segment_length);
1382                break;
1383            case DVBSUB_REGION_SEGMENT:
1384                dvbsub_parse_region_segment(avctx, p, segment_length);
1385                break;
1386            case DVBSUB_CLUT_SEGMENT:
1387                dvbsub_parse_clut_segment(avctx, p, segment_length);
1388                break;
1389            case DVBSUB_OBJECT_SEGMENT:
1390                dvbsub_parse_object_segment(avctx, p, segment_length);
1391                break;
1392            case DVBSUB_DISPLAY_SEGMENT:
1393                *data_size = dvbsub_display_end_segment(avctx, p, segment_length, sub);
1394                break;
1395            default:
1396                dprintf(avctx, "Subtitling segment type 0x%x, page id %d, length %d\n",
1397                        segment_type, page_id, segment_length);
1398                break;
1399            }
1400        }
1401
1402        p += segment_length;
1403    }
1404
1405    if (p != p_end) {
1406        dprintf(avctx, "Junk at end of packet\n");
1407        return -1;
1408    }
1409
1410    return buf_size;
1411}
1412
1413
1414AVCodec dvbsub_decoder = {
1415    "dvbsub",
1416    AVMEDIA_TYPE_SUBTITLE,
1417    CODEC_ID_DVB_SUBTITLE,
1418    sizeof(DVBSubContext),
1419    dvbsub_init_decoder,
1420    NULL,
1421    dvbsub_close_decoder,
1422    dvbsub_decode,
1423    .long_name = NULL_IF_CONFIG_SMALL("DVB subtitles"),
1424};
1425