GCC Code Coverage Report
Directory: ../../../ffmpeg/ Exec Total Coverage
File: src/libavcodec/dvbsub.c Lines: 0 311 0.0 %
Date: 2020-07-11 02:49:52 Branches: 0 234 0.0 %

Line Branch Exec Source
1
/*
2
 * DVB subtitle encoding
3
 * Copyright (c) 2005 Fabrice Bellard
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 "bytestream.h"
23
#include "libavutil/colorspace.h"
24
25
typedef struct DVBSubtitleContext {
26
    int object_version;
27
} DVBSubtitleContext;
28
29
#define PUTBITS2(val)\
30
{\
31
    bitbuf |= (val) << bitcnt;\
32
    bitcnt -= 2;\
33
    if (bitcnt < 0) {\
34
        bitcnt = 6;\
35
        *q++ = bitbuf;\
36
        bitbuf = 0;\
37
    }\
38
}
39
40
static int dvb_encode_rle2(uint8_t **pq, int buf_size,
41
                           const uint8_t *bitmap, int linesize,
42
                           int w, int h)
43
{
44
    uint8_t *q, *line_begin;
45
    unsigned int bitbuf;
46
    int bitcnt;
47
    int x, y, len, x1, v, color;
48
49
    q = *pq;
50
51
    for(y = 0; y < h; y++) {
52
        // Worst case line is 3 bits per value + 4 bytes overhead
53
        if (buf_size * 8 < w * 3 + 32)
54
            return AVERROR_BUFFER_TOO_SMALL;
55
        line_begin = q;
56
        *q++ = 0x10;
57
        bitbuf = 0;
58
        bitcnt = 6;
59
60
        x = 0;
61
        while (x < w) {
62
            x1 = x;
63
            color = bitmap[x1++];
64
            while (x1 < w && bitmap[x1] == color)
65
                x1++;
66
            len = x1 - x;
67
            if (color == 0 && len == 2) {
68
                PUTBITS2(0);
69
                PUTBITS2(0);
70
                PUTBITS2(1);
71
            } else if (len >= 3 && len <= 10) {
72
                v = len - 3;
73
                PUTBITS2(0);
74
                PUTBITS2((v >> 2) | 2);
75
                PUTBITS2(v & 3);
76
                PUTBITS2(color);
77
            } else if (len >= 12 && len <= 27) {
78
                v = len - 12;
79
                PUTBITS2(0);
80
                PUTBITS2(0);
81
                PUTBITS2(2);
82
                PUTBITS2(v >> 2);
83
                PUTBITS2(v & 3);
84
                PUTBITS2(color);
85
            } else if (len >= 29) {
86
                /* length = 29 ... 284 */
87
                if (len > 284)
88
                    len = 284;
89
                v = len - 29;
90
                PUTBITS2(0);
91
                PUTBITS2(0);
92
                PUTBITS2(3);
93
                PUTBITS2((v >> 6));
94
                PUTBITS2((v >> 4) & 3);
95
                PUTBITS2((v >> 2) & 3);
96
                PUTBITS2(v & 3);
97
                PUTBITS2(color);
98
            } else {
99
                PUTBITS2(color);
100
                if (color == 0) {
101
                    PUTBITS2(1);
102
                }
103
                len = 1;
104
            }
105
            x += len;
106
        }
107
        /* end of line */
108
        PUTBITS2(0);
109
        PUTBITS2(0);
110
        PUTBITS2(0);
111
        if (bitcnt != 6) {
112
            *q++ = bitbuf;
113
        }
114
        *q++ = 0xf0;
115
        bitmap += linesize;
116
        buf_size -= q - line_begin;
117
    }
118
    len = q - *pq;
119
    *pq = q;
120
    return len;
121
}
122
123
#define PUTBITS4(val)\
124
{\
125
    bitbuf |= (val) << bitcnt;\
126
    bitcnt -= 4;\
127
    if (bitcnt < 0) {\
128
        bitcnt = 4;\
129
        *q++ = bitbuf;\
130
        bitbuf = 0;\
131
    }\
132
}
133
134
/* some DVB decoders only implement 4 bits/pixel */
135
static int dvb_encode_rle4(uint8_t **pq, int buf_size,
136
                           const uint8_t *bitmap, int linesize,
137
                           int w, int h)
138
{
139
    uint8_t *q, *line_begin;
140
    unsigned int bitbuf;
141
    int bitcnt;
142
    int x, y, len, x1, v, color;
143
144
    q = *pq;
145
146
    for(y = 0; y < h; y++) {
147
        // Worst case line is 6 bits per value, + 4 bytes overhead
148
        if (buf_size * 8 < w * 6 + 32)
149
            return AVERROR_BUFFER_TOO_SMALL;
150
        line_begin = q;
151
        *q++ = 0x11;
152
        bitbuf = 0;
153
        bitcnt = 4;
154
155
        x = 0;
156
        while (x < w) {
157
            x1 = x;
158
            color = bitmap[x1++];
159
            while (x1 < w && bitmap[x1] == color)
160
                x1++;
161
            len = x1 - x;
162
            if (color == 0 && len == 2) {
163
                PUTBITS4(0);
164
                PUTBITS4(0xd);
165
            } else if (color == 0 && (len >= 3 && len <= 9)) {
166
                PUTBITS4(0);
167
                PUTBITS4(len - 2);
168
            } else if (len >= 4 && len <= 7) {
169
                PUTBITS4(0);
170
                PUTBITS4(8 + len - 4);
171
                PUTBITS4(color);
172
            } else if (len >= 9 && len <= 24) {
173
                PUTBITS4(0);
174
                PUTBITS4(0xe);
175
                PUTBITS4(len - 9);
176
                PUTBITS4(color);
177
            } else if (len >= 25) {
178
                if (len > 280)
179
                    len = 280;
180
                v = len - 25;
181
                PUTBITS4(0);
182
                PUTBITS4(0xf);
183
                PUTBITS4(v >> 4);
184
                PUTBITS4(v & 0xf);
185
                PUTBITS4(color);
186
            } else {
187
                PUTBITS4(color);
188
                if (color == 0) {
189
                    PUTBITS4(0xc);
190
                }
191
                len = 1;
192
            }
193
            x += len;
194
        }
195
        /* end of line */
196
        PUTBITS4(0);
197
        PUTBITS4(0);
198
        if (bitcnt != 4) {
199
            *q++ = bitbuf;
200
        }
201
        *q++ = 0xf0;
202
        bitmap += linesize;
203
        buf_size -= q - line_begin;
204
    }
205
    len = q - *pq;
206
    *pq = q;
207
    return len;
208
}
209
210
static int dvb_encode_rle8(uint8_t **pq, int buf_size,
211
                           const uint8_t *bitmap, int linesize,
212
                           int w, int h)
213
{
214
    uint8_t *q, *line_begin;
215
    int x, y, len, x1, color;
216
217
    q = *pq;
218
219
    for (y = 0; y < h; y++) {
220
        // Worst case line is 12 bits per value, + 3 bytes overhead
221
        if (buf_size * 8 < w * 12 + 24)
222
            return AVERROR_BUFFER_TOO_SMALL;
223
        line_begin = q;
224
        *q++ = 0x12;
225
226
        x = 0;
227
        while (x < w) {
228
            x1 = x;
229
            color = bitmap[x1++];
230
            while (x1 < w && bitmap[x1] == color)
231
                x1++;
232
            len = x1 - x;
233
            if (len == 1 && color) {
234
                // 00000001 to 11111111           1 pixel in colour x
235
                *q++ = color;
236
            } else {
237
                if (color == 0x00) {
238
                    // 00000000 0LLLLLLL          L pixels (1-127) in colour 0 (L > 0)
239
                    len = FFMIN(len, 127);
240
                    *q++ = 0x00;
241
                    *q++ = len;
242
                } else if (len > 2) {
243
                    // 00000000 1LLLLLLL CCCCCCCC L pixels (3-127) in colour C (L > 2)
244
                    len = FFMIN(len, 127);
245
                    *q++ = 0x00;
246
                    *q++ = 0x80+len;
247
                    *q++ = color;
248
                }
249
                else if (len == 2) {
250
                    *q++ = color;
251
                    *q++ = color;
252
                } else {
253
                    *q++ = color;
254
                    len = 1;
255
                }
256
            }
257
            x += len;
258
        }
259
        /* end of line */
260
        // 00000000 end of 8-bit/pixel_code_string
261
        *q++ = 0x00;
262
        *q++ = 0xf0;
263
        bitmap += linesize;
264
        buf_size -= q - line_begin;
265
    }
266
    len = q - *pq;
267
    *pq = q;
268
    return len;
269
}
270
271
static int encode_dvb_subtitles(AVCodecContext *avctx,
272
                                uint8_t *outbuf, int buf_size,
273
                                const AVSubtitle *h)
274
{
275
    DVBSubtitleContext *s = avctx->priv_data;
276
    uint8_t *q, *pseg_len;
277
    int page_id, region_id, clut_id, object_id, i, bpp_index, page_state;
278
279
280
    q = outbuf;
281
282
    page_id = 1;
283
284
    if (h->num_rects && !h->rects)
285
        return AVERROR(EINVAL);
286
287
    if (avctx->width > 0 && avctx->height > 0) {
288
        if (buf_size < 11)
289
            return AVERROR_BUFFER_TOO_SMALL;
290
        /* display definition segment */
291
        *q++ = 0x0f; /* sync_byte */
292
        *q++ = 0x14; /* segment_type */
293
        bytestream_put_be16(&q, page_id);
294
        pseg_len = q;
295
        q += 2; /* segment length */
296
        *q++ = 0x00; /* dds version number & display window flag */
297
        bytestream_put_be16(&q, avctx->width - 1); /* display width */
298
        bytestream_put_be16(&q, avctx->height - 1); /* display height */
299
        bytestream_put_be16(&pseg_len, q - pseg_len - 2);
300
        buf_size -= 11;
301
    }
302
303
    /* page composition segment */
304
305
    if (buf_size < 8 + h->num_rects * 6)
306
        return AVERROR_BUFFER_TOO_SMALL;
307
    *q++ = 0x0f; /* sync_byte */
308
    *q++ = 0x10; /* segment_type */
309
    bytestream_put_be16(&q, page_id);
310
    pseg_len = q;
311
    q += 2; /* segment length */
312
    *q++ = 30; /* page_timeout (seconds) */
313
    page_state = 2; /* mode change */
314
    /* page_version = 0 + page_state */
315
    *q++ = (s->object_version << 4) | (page_state << 2) | 3;
316
317
    for (region_id = 0; region_id < h->num_rects; region_id++) {
318
        *q++ = region_id;
319
        *q++ = 0xff; /* reserved */
320
        bytestream_put_be16(&q, h->rects[region_id]->x); /* left pos */
321
        bytestream_put_be16(&q, h->rects[region_id]->y); /* top pos */
322
    }
323
324
    bytestream_put_be16(&pseg_len, q - pseg_len - 2);
325
    buf_size -= 8 + h->num_rects * 6;
326
327
    if (h->num_rects) {
328
        for (clut_id = 0; clut_id < h->num_rects; clut_id++) {
329
            if (buf_size < 6 + h->rects[clut_id]->nb_colors * 6)
330
                return AVERROR_BUFFER_TOO_SMALL;
331
332
            /* CLUT segment */
333
334
            if (h->rects[clut_id]->nb_colors <= 4) {
335
                /* 2 bpp, some decoders do not support it correctly */
336
                bpp_index = 0;
337
            } else if (h->rects[clut_id]->nb_colors <= 16) {
338
                /* 4 bpp, standard encoding */
339
                bpp_index = 1;
340
            } else if (h->rects[clut_id]->nb_colors <= 256) {
341
                /* 8 bpp, standard encoding */
342
                bpp_index = 2;
343
            } else {
344
                return AVERROR(EINVAL);
345
            }
346
347
348
            /* CLUT segment */
349
            *q++ = 0x0f; /* sync byte */
350
            *q++ = 0x12; /* CLUT definition segment */
351
            bytestream_put_be16(&q, page_id);
352
            pseg_len = q;
353
            q += 2; /* segment length */
354
            *q++ = clut_id;
355
            *q++ = (0 << 4) | 0xf; /* version = 0 */
356
357
            for(i = 0; i < h->rects[clut_id]->nb_colors; i++) {
358
                *q++ = i; /* clut_entry_id */
359
                *q++ = (1 << (7 - bpp_index)) | (0xf << 1) | 1; /* 2 bits/pixel full range */
360
                {
361
                    int a, r, g, b;
362
                    uint32_t x= ((uint32_t*)h->rects[clut_id]->data[1])[i];
363
                    a = (x >> 24) & 0xff;
364
                    r = (x >> 16) & 0xff;
365
                    g = (x >>  8) & 0xff;
366
                    b = (x >>  0) & 0xff;
367
368
                    *q++ = RGB_TO_Y_CCIR(r, g, b);
369
                    *q++ = RGB_TO_V_CCIR(r, g, b, 0);
370
                    *q++ = RGB_TO_U_CCIR(r, g, b, 0);
371
                    *q++ = 255 - a;
372
                }
373
            }
374
375
            bytestream_put_be16(&pseg_len, q - pseg_len - 2);
376
            buf_size -= 6 + h->rects[clut_id]->nb_colors * 6;
377
        }
378
    }
379
380
    if (buf_size < h->num_rects * 22)
381
        return AVERROR_BUFFER_TOO_SMALL;
382
    for (region_id = 0; region_id < h->num_rects; region_id++) {
383
384
        /* region composition segment */
385
386
        if (h->rects[region_id]->nb_colors <= 4) {
387
            /* 2 bpp, some decoders do not support it correctly */
388
            bpp_index = 0;
389
        } else if (h->rects[region_id]->nb_colors <= 16) {
390
            /* 4 bpp, standard encoding */
391
            bpp_index = 1;
392
        } else if (h->rects[region_id]->nb_colors <= 256) {
393
            /* 8 bpp, standard encoding */
394
            bpp_index = 2;
395
        } else {
396
            return AVERROR(EINVAL);
397
        }
398
399
        *q++ = 0x0f; /* sync_byte */
400
        *q++ = 0x11; /* segment_type */
401
        bytestream_put_be16(&q, page_id);
402
        pseg_len = q;
403
        q += 2; /* segment length */
404
        *q++ = region_id;
405
        *q++ = (s->object_version << 4) | (0 << 3) | 0x07; /* version , no fill */
406
        bytestream_put_be16(&q, h->rects[region_id]->w); /* region width */
407
        bytestream_put_be16(&q, h->rects[region_id]->h); /* region height */
408
        *q++ = ((1 + bpp_index) << 5) | ((1 + bpp_index) << 2) | 0x03;
409
        *q++ = region_id; /* clut_id == region_id */
410
        *q++ = 0; /* 8 bit fill colors */
411
        *q++ = 0x03; /* 4 bit and 2 bit fill colors */
412
413
        bytestream_put_be16(&q, region_id); /* object_id == region_id */
414
        *q++ = (0 << 6) | (0 << 4);
415
        *q++ = 0;
416
        *q++ = 0xf0;
417
        *q++ = 0;
418
419
        bytestream_put_be16(&pseg_len, q - pseg_len - 2);
420
    }
421
    buf_size -= h->num_rects * 22;
422
423
    if (h->num_rects) {
424
425
        for (object_id = 0; object_id < h->num_rects; object_id++) {
426
            int (*dvb_encode_rle)(uint8_t **pq, int buf_size,
427
                                  const uint8_t *bitmap, int linesize,
428
                                  int w, int h);
429
430
            if (buf_size < 13)
431
                return AVERROR_BUFFER_TOO_SMALL;
432
433
            /* bpp_index maths */
434
            if (h->rects[object_id]->nb_colors <= 4) {
435
                /* 2 bpp, some decoders do not support it correctly */
436
                dvb_encode_rle = dvb_encode_rle2;
437
            } else if (h->rects[object_id]->nb_colors <= 16) {
438
                /* 4 bpp, standard encoding */
439
                dvb_encode_rle = dvb_encode_rle4;
440
            } else if (h->rects[object_id]->nb_colors <= 256) {
441
                /* 8 bpp, standard encoding */
442
                dvb_encode_rle = dvb_encode_rle8;
443
            } else {
444
                return AVERROR(EINVAL);
445
            }
446
447
            /* Object Data segment */
448
            *q++ = 0x0f; /* sync byte */
449
            *q++ = 0x13;
450
            bytestream_put_be16(&q, page_id);
451
            pseg_len = q;
452
            q += 2; /* segment length */
453
454
            bytestream_put_be16(&q, object_id);
455
            *q++ = (s->object_version << 4) | (0 << 2) | (0 << 1) | 1; /* version = 0,
456
                                                                       onject_coding_method,
457
                                                                       non_modifying_color_flag */
458
            {
459
                uint8_t *ptop_field_len, *pbottom_field_len, *top_ptr, *bottom_ptr;
460
                int ret;
461
462
                ptop_field_len = q;
463
                q += 2;
464
                pbottom_field_len = q;
465
                q += 2;
466
                buf_size -= 13;
467
468
                top_ptr = q;
469
                ret = dvb_encode_rle(&q, buf_size,
470
                                     h->rects[object_id]->data[0],
471
                                     h->rects[object_id]->w * 2,
472
                                     h->rects[object_id]->w,
473
                                     h->rects[object_id]->h >> 1);
474
                if (ret < 0)
475
                    return ret;
476
                buf_size -= ret;
477
                bottom_ptr = q;
478
                ret = dvb_encode_rle(&q, buf_size,
479
                                     h->rects[object_id]->data[0] + h->rects[object_id]->w,
480
                                     h->rects[object_id]->w * 2,
481
                                     h->rects[object_id]->w,
482
                                     h->rects[object_id]->h >> 1);
483
                if (ret < 0)
484
                    return ret;
485
                buf_size -= ret;
486
487
                bytestream_put_be16(&ptop_field_len, bottom_ptr - top_ptr);
488
                bytestream_put_be16(&pbottom_field_len, q - bottom_ptr);
489
            }
490
491
            bytestream_put_be16(&pseg_len, q - pseg_len - 2);
492
        }
493
    }
494
495
    /* end of display set segment */
496
497
    if (buf_size < 6)
498
        return AVERROR_BUFFER_TOO_SMALL;
499
    *q++ = 0x0f; /* sync_byte */
500
    *q++ = 0x80; /* segment_type */
501
    bytestream_put_be16(&q, page_id);
502
    pseg_len = q;
503
    q += 2; /* segment length */
504
505
    bytestream_put_be16(&pseg_len, q - pseg_len - 2);
506
    buf_size -= 6;
507
508
    s->object_version = (s->object_version + 1) & 0xf;
509
    return q - outbuf;
510
}
511
512
static int dvbsub_encode(AVCodecContext *avctx,
513
                         unsigned char *buf, int buf_size,
514
                         const AVSubtitle *sub)
515
{
516
    int ret;
517
518
    ret = encode_dvb_subtitles(avctx, buf, buf_size, sub);
519
    return ret;
520
}
521
522
AVCodec ff_dvbsub_encoder = {
523
    .name           = "dvbsub",
524
    .long_name      = NULL_IF_CONFIG_SMALL("DVB subtitles"),
525
    .type           = AVMEDIA_TYPE_SUBTITLE,
526
    .id             = AV_CODEC_ID_DVB_SUBTITLE,
527
    .priv_data_size = sizeof(DVBSubtitleContext),
528
    .encode_sub     = dvbsub_encode,
529
};