GCC Code Coverage Report
Directory: ../../../ffmpeg/ Exec Total Coverage
File: src/libavcodec/ccaption_dec.c Lines: 256 343 74.6 %
Date: 2019-11-22 03:34:36 Branches: 154 227 67.8 %

Line Branch Exec Source
1
/*
2
 * Closed Caption Decoding
3
 * Copyright (c) 2015 Anshul Maheshwari
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
22
#include "avcodec.h"
23
#include "ass.h"
24
#include "libavutil/opt.h"
25
26
#define SCREEN_ROWS 15
27
#define SCREEN_COLUMNS 32
28
29
#define SET_FLAG(var, val)   ( (var) |=   ( 1 << (val)) )
30
#define UNSET_FLAG(var, val) ( (var) &=  ~( 1 << (val)) )
31
#define CHECK_FLAG(var, val) ( (var) &    ( 1 << (val)) )
32
33
static const AVRational ms_tb = {1, 1000};
34
35
/*
36
 * TODO list
37
 * 1) handle font and color completely
38
 */
39
enum cc_mode {
40
    CCMODE_POPON,
41
    CCMODE_PAINTON,
42
    CCMODE_ROLLUP,
43
    CCMODE_TEXT,
44
};
45
46
enum cc_color_code {
47
    CCCOL_WHITE,
48
    CCCOL_GREEN,
49
    CCCOL_BLUE,
50
    CCCOL_CYAN,
51
    CCCOL_RED,
52
    CCCOL_YELLOW,
53
    CCCOL_MAGENTA,
54
    CCCOL_USERDEFINED,
55
    CCCOL_BLACK,
56
    CCCOL_TRANSPARENT,
57
};
58
59
enum cc_font {
60
    CCFONT_REGULAR,
61
    CCFONT_ITALICS,
62
    CCFONT_UNDERLINED,
63
    CCFONT_UNDERLINED_ITALICS,
64
};
65
66
enum cc_charset {
67
    CCSET_BASIC_AMERICAN,
68
    CCSET_SPECIAL_AMERICAN,
69
    CCSET_EXTENDED_SPANISH_FRENCH_MISC,
70
    CCSET_EXTENDED_PORTUGUESE_GERMAN_DANISH,
71
};
72
73
static const char *charset_overrides[4][128] =
74
{
75
    [CCSET_BASIC_AMERICAN] = {
76
        [0x27] = "\u2019",
77
        [0x2a] = "\u00e1",
78
        [0x5c] = "\u00e9",
79
        [0x5e] = "\u00ed",
80
        [0x5f] = "\u00f3",
81
        [0x60] = "\u00fa",
82
        [0x7b] = "\u00e7",
83
        [0x7c] = "\u00f7",
84
        [0x7d] = "\u00d1",
85
        [0x7e] = "\u00f1",
86
        [0x7f] = "\u2588"
87
    },
88
    [CCSET_SPECIAL_AMERICAN] = {
89
        [0x30] = "\u00ae",
90
        [0x31] = "\u00b0",
91
        [0x32] = "\u00bd",
92
        [0x33] = "\u00bf",
93
        [0x34] = "\u2122",
94
        [0x35] = "\u00a2",
95
        [0x36] = "\u00a3",
96
        [0x37] = "\u266a",
97
        [0x38] = "\u00e0",
98
        [0x39] = "\u00A0",
99
        [0x3a] = "\u00e8",
100
        [0x3b] = "\u00e2",
101
        [0x3c] = "\u00ea",
102
        [0x3d] = "\u00ee",
103
        [0x3e] = "\u00f4",
104
        [0x3f] = "\u00fb",
105
    },
106
    [CCSET_EXTENDED_SPANISH_FRENCH_MISC] = {
107
        [0x20] = "\u00c1",
108
        [0x21] = "\u00c9",
109
        [0x22] = "\u00d3",
110
        [0x23] = "\u00da",
111
        [0x24] = "\u00dc",
112
        [0x25] = "\u00fc",
113
        [0x26] = "\u00b4",
114
        [0x27] = "\u00a1",
115
        [0x28] = "*",
116
        [0x29] = "\u2018",
117
        [0x2a] = "-",
118
        [0x2b] = "\u00a9",
119
        [0x2c] = "\u2120",
120
        [0x2d] = "\u00b7",
121
        [0x2e] = "\u201c",
122
        [0x2f] = "\u201d",
123
        [0x30] = "\u00c0",
124
        [0x31] = "\u00c2",
125
        [0x32] = "\u00c7",
126
        [0x33] = "\u00c8",
127
        [0x34] = "\u00ca",
128
        [0x35] = "\u00cb",
129
        [0x36] = "\u00eb",
130
        [0x37] = "\u00ce",
131
        [0x38] = "\u00cf",
132
        [0x39] = "\u00ef",
133
        [0x3a] = "\u00d4",
134
        [0x3b] = "\u00d9",
135
        [0x3c] = "\u00f9",
136
        [0x3d] = "\u00db",
137
        [0x3e] = "\u00ab",
138
        [0x3f] = "\u00bb",
139
    },
140
    [CCSET_EXTENDED_PORTUGUESE_GERMAN_DANISH] = {
141
        [0x20] = "\u00c3",
142
        [0x21] = "\u00e3",
143
        [0x22] = "\u00cd",
144
        [0x23] = "\u00cc",
145
        [0x24] = "\u00ec",
146
        [0x25] = "\u00d2",
147
        [0x26] = "\u00f2",
148
        [0x27] = "\u00d5",
149
        [0x28] = "\u00f5",
150
        [0x29] = "{",
151
        [0x2a] = "}",
152
        [0x2b] = "\\",
153
        [0x2c] = "^",
154
        [0x2d] = "_",
155
        [0x2e] = "|",
156
        [0x2f] = "~",
157
        [0x30] = "\u00c4",
158
        [0x31] = "\u00e4",
159
        [0x32] = "\u00d6",
160
        [0x33] = "\u00f6",
161
        [0x34] = "\u00df",
162
        [0x35] = "\u00a5",
163
        [0x36] = "\u00a4",
164
        [0x37] = "\u00a6",
165
        [0x38] = "\u00c5",
166
        [0x39] = "\u00e5",
167
        [0x3a] = "\u00d8",
168
        [0x3b] = "\u00f8",
169
        [0x3c] = "\u250c",
170
        [0x3d] = "\u2510",
171
        [0x3e] = "\u2514",
172
        [0x3f] = "\u2518",
173
    },
174
};
175
176
static const unsigned char pac2_attribs[32][3] = // Color, font, ident
177
{
178
    { CCCOL_WHITE,   CCFONT_REGULAR,            0 },  // 0x40 || 0x60
179
    { CCCOL_WHITE,   CCFONT_UNDERLINED,         0 },  // 0x41 || 0x61
180
    { CCCOL_GREEN,   CCFONT_REGULAR,            0 },  // 0x42 || 0x62
181
    { CCCOL_GREEN,   CCFONT_UNDERLINED,         0 },  // 0x43 || 0x63
182
    { CCCOL_BLUE,    CCFONT_REGULAR,            0 },  // 0x44 || 0x64
183
    { CCCOL_BLUE,    CCFONT_UNDERLINED,         0 },  // 0x45 || 0x65
184
    { CCCOL_CYAN,    CCFONT_REGULAR,            0 },  // 0x46 || 0x66
185
    { CCCOL_CYAN,    CCFONT_UNDERLINED,         0 },  // 0x47 || 0x67
186
    { CCCOL_RED,     CCFONT_REGULAR,            0 },  // 0x48 || 0x68
187
    { CCCOL_RED,     CCFONT_UNDERLINED,         0 },  // 0x49 || 0x69
188
    { CCCOL_YELLOW,  CCFONT_REGULAR,            0 },  // 0x4a || 0x6a
189
    { CCCOL_YELLOW,  CCFONT_UNDERLINED,         0 },  // 0x4b || 0x6b
190
    { CCCOL_MAGENTA, CCFONT_REGULAR,            0 },  // 0x4c || 0x6c
191
    { CCCOL_MAGENTA, CCFONT_UNDERLINED,         0 },  // 0x4d || 0x6d
192
    { CCCOL_WHITE,   CCFONT_ITALICS,            0 },  // 0x4e || 0x6e
193
    { CCCOL_WHITE,   CCFONT_UNDERLINED_ITALICS, 0 },  // 0x4f || 0x6f
194
    { CCCOL_WHITE,   CCFONT_REGULAR,            0 },  // 0x50 || 0x70
195
    { CCCOL_WHITE,   CCFONT_UNDERLINED,         0 },  // 0x51 || 0x71
196
    { CCCOL_WHITE,   CCFONT_REGULAR,            4 },  // 0x52 || 0x72
197
    { CCCOL_WHITE,   CCFONT_UNDERLINED,         4 },  // 0x53 || 0x73
198
    { CCCOL_WHITE,   CCFONT_REGULAR,            8 },  // 0x54 || 0x74
199
    { CCCOL_WHITE,   CCFONT_UNDERLINED,         8 },  // 0x55 || 0x75
200
    { CCCOL_WHITE,   CCFONT_REGULAR,           12 },  // 0x56 || 0x76
201
    { CCCOL_WHITE,   CCFONT_UNDERLINED,        12 },  // 0x57 || 0x77
202
    { CCCOL_WHITE,   CCFONT_REGULAR,           16 },  // 0x58 || 0x78
203
    { CCCOL_WHITE,   CCFONT_UNDERLINED,        16 },  // 0x59 || 0x79
204
    { CCCOL_WHITE,   CCFONT_REGULAR,           20 },  // 0x5a || 0x7a
205
    { CCCOL_WHITE,   CCFONT_UNDERLINED,        20 },  // 0x5b || 0x7b
206
    { CCCOL_WHITE,   CCFONT_REGULAR,           24 },  // 0x5c || 0x7c
207
    { CCCOL_WHITE,   CCFONT_UNDERLINED,        24 },  // 0x5d || 0x7d
208
    { CCCOL_WHITE,   CCFONT_REGULAR,           28 },  // 0x5e || 0x7e
209
    { CCCOL_WHITE,   CCFONT_UNDERLINED,        28 }   // 0x5f || 0x7f
210
    /* total 32 entries */
211
};
212
213
struct Screen {
214
    /* +1 is used to compensate null character of string */
215
    uint8_t characters[SCREEN_ROWS+1][SCREEN_COLUMNS+1];
216
    uint8_t charsets[SCREEN_ROWS+1][SCREEN_COLUMNS+1];
217
    uint8_t colors[SCREEN_ROWS+1][SCREEN_COLUMNS+1];
218
    uint8_t fonts[SCREEN_ROWS+1][SCREEN_COLUMNS+1];
219
    /*
220
     * Bitmask of used rows; if a bit is not set, the
221
     * corresponding row is not used.
222
     * for setting row 1  use row | (1 << 0)
223
     * for setting row 15 use row | (1 << 14)
224
     */
225
    int16_t row_used;
226
};
227
228
typedef struct CCaptionSubContext {
229
    AVClass *class;
230
    int real_time;
231
    struct Screen screen[2];
232
    int active_screen;
233
    uint8_t cursor_row;
234
    uint8_t cursor_column;
235
    uint8_t cursor_color;
236
    uint8_t cursor_font;
237
    uint8_t cursor_charset;
238
    AVBPrint buffer;
239
    int buffer_changed;
240
    int rollup;
241
    enum cc_mode mode;
242
    int64_t start_time;
243
    /* visible screen time */
244
    int64_t startv_time;
245
    int64_t end_time;
246
    int screen_touched;
247
    int64_t last_real_time;
248
    char prev_cmd[2];
249
    /* buffer to store pkt data */
250
    uint8_t *pktbuf;
251
    int pktbuf_size;
252
    int readorder;
253
} CCaptionSubContext;
254
255
256
8
static av_cold int init_decoder(AVCodecContext *avctx)
257
{
258
    int ret;
259
8
    CCaptionSubContext *ctx = avctx->priv_data;
260
261
8
    av_bprint_init(&ctx->buffer, 0, AV_BPRINT_SIZE_UNLIMITED);
262
    /* taking by default roll up to 2 */
263
8
    ctx->mode = CCMODE_ROLLUP;
264
8
    ctx->rollup = 2;
265
8
    ctx->cursor_row = 10;
266
8
    ret = ff_ass_subtitle_header(avctx, "Monospace",
267
                                 ASS_DEFAULT_FONT_SIZE,
268
                                 ASS_DEFAULT_COLOR,
269
                                 ASS_DEFAULT_BACK_COLOR,
270
                                 ASS_DEFAULT_BOLD,
271
                                 ASS_DEFAULT_ITALIC,
272
                                 ASS_DEFAULT_UNDERLINE,
273
                                 3,
274
                                 ASS_DEFAULT_ALIGNMENT);
275
8
    if (ret < 0) {
276
        return ret;
277
    }
278
279
8
    return ret;
280
}
281
282
8
static av_cold int close_decoder(AVCodecContext *avctx)
283
{
284
8
    CCaptionSubContext *ctx = avctx->priv_data;
285
8
    av_bprint_finalize(&ctx->buffer, NULL);
286
8
    av_freep(&ctx->pktbuf);
287
8
    ctx->pktbuf_size = 0;
288
8
    return 0;
289
}
290
291
static void flush_decoder(AVCodecContext *avctx)
292
{
293
    CCaptionSubContext *ctx = avctx->priv_data;
294
    ctx->screen[0].row_used = 0;
295
    ctx->screen[1].row_used = 0;
296
    ctx->prev_cmd[0] = 0;
297
    ctx->prev_cmd[1] = 0;
298
    ctx->mode = CCMODE_ROLLUP;
299
    ctx->rollup = 2;
300
    ctx->cursor_row = 10;
301
    ctx->cursor_column = 0;
302
    ctx->cursor_font = 0;
303
    ctx->cursor_color = 0;
304
    ctx->cursor_charset = 0;
305
    ctx->active_screen = 0;
306
    ctx->last_real_time = 0;
307
    ctx->screen_touched = 0;
308
    ctx->buffer_changed = 0;
309
    if (!(avctx->flags2 & AV_CODEC_FLAG2_RO_FLUSH_NOOP))
310
        ctx->readorder = 0;
311
    av_bprint_clear(&ctx->buffer);
312
}
313
314
/**
315
 * @param ctx closed caption context just to print log
316
 */
317
5815
static void write_char(CCaptionSubContext *ctx, struct Screen *screen, char ch)
318
{
319
5815
    uint8_t col = ctx->cursor_column;
320
5815
    char *row = screen->characters[ctx->cursor_row];
321
5815
    char *font = screen->fonts[ctx->cursor_row];
322
5815
    char *charset = screen->charsets[ctx->cursor_row];
323
324
5815
    if (col < SCREEN_COLUMNS) {
325
5808
        row[col] = ch;
326
5808
        font[col] = ctx->cursor_font;
327
5808
        charset[col] = ctx->cursor_charset;
328
5808
        ctx->cursor_charset = CCSET_BASIC_AMERICAN;
329
5808
        if (ch) ctx->cursor_column++;
330
5808
        return;
331
    }
332
    /* We have extra space at end only for null character */
333

7
    else if (col == SCREEN_COLUMNS && ch == 0) {
334
7
        row[col] = ch;
335
7
        return;
336
    }
337
    else {
338
        av_log(ctx, AV_LOG_WARNING, "Data Ignored since exceeding screen width\n");
339
        return;
340
    }
341
}
342
343
/**
344
 * This function after validating parity bit, also remove it from data pair.
345
 * The first byte doesn't pass parity, we replace it with a solid blank
346
 * and process the pair.
347
 * If the second byte doesn't pass parity, it returns INVALIDDATA
348
 * user can ignore the whole pair and pass the other pair.
349
 */
350
8253
static int validate_cc_data_pair(uint8_t *cc_data_pair)
351
{
352
8253
    uint8_t cc_valid = (*cc_data_pair & 4) >>2;
353
8253
    uint8_t cc_type = *cc_data_pair & 3;
354
355
8253
    if (!cc_valid)
356
4582
        return AVERROR_INVALIDDATA;
357
358
    // if EIA-608 data then verify parity.
359

3671
    if (cc_type==0 || cc_type==1) {
360
3393
        if (!av_parity(cc_data_pair[2])) {
361
            return AVERROR_INVALIDDATA;
362
        }
363
3393
        if (!av_parity(cc_data_pair[1])) {
364
            cc_data_pair[1]=0x7F;
365
        }
366
    }
367
368
    //Skip non-data
369

3671
    if ((cc_data_pair[0] == 0xFA || cc_data_pair[0] == 0xFC || cc_data_pair[0] == 0xFD)
370

2989
         && (cc_data_pair[1] & 0x7F) == 0 && (cc_data_pair[2] & 0x7F) == 0)
371
434
        return AVERROR_PATCHWELCOME;
372
373
    //skip 708 data
374

3237
    if (cc_type == 3 || cc_type == 2)
375
278
        return AVERROR_PATCHWELCOME;
376
377
    /* remove parity bit */
378
2959
    cc_data_pair[1] &= 0x7F;
379
2959
    cc_data_pair[2] &= 0x7F;
380
381
2959
    return 0;
382
}
383
384
1811
static struct Screen *get_writing_screen(CCaptionSubContext *ctx)
385
{
386
1811
    switch (ctx->mode) {
387
1676
    case CCMODE_POPON:
388
        // use Inactive screen
389
1676
        return ctx->screen + !ctx->active_screen;
390
135
    case CCMODE_PAINTON:
391
    case CCMODE_ROLLUP:
392
    case CCMODE_TEXT:
393
        // use active screen
394
135
        return ctx->screen + ctx->active_screen;
395
    }
396
    /* It was never an option */
397
    return NULL;
398
}
399
400
9
static void roll_up(CCaptionSubContext *ctx)
401
{
402
    struct Screen *screen;
403
    int i, keep_lines;
404
405
9
    if (ctx->mode == CCMODE_TEXT)
406
        return;
407
408
9
    screen = get_writing_screen(ctx);
409
410
    /* +1 signify cursor_row starts from 0
411
     * Can't keep lines less then row cursor pos
412
     */
413
9
    keep_lines = FFMIN(ctx->cursor_row + 1, ctx->rollup);
414
415
144
    for (i = 0; i < SCREEN_ROWS; i++) {
416

135
        if (i > ctx->cursor_row - keep_lines && i <= ctx->cursor_row)
417
18
            continue;
418
117
        UNSET_FLAG(screen->row_used, i);
419
    }
420
421

23
    for (i = 0; i < keep_lines && screen->row_used; i++) {
422
14
        const int i_row = ctx->cursor_row - keep_lines + i + 1;
423
424
14
        memcpy(screen->characters[i_row], screen->characters[i_row+1], SCREEN_COLUMNS);
425
14
        memcpy(screen->colors[i_row], screen->colors[i_row+1], SCREEN_COLUMNS);
426
14
        memcpy(screen->fonts[i_row], screen->fonts[i_row+1], SCREEN_COLUMNS);
427
14
        memcpy(screen->charsets[i_row], screen->charsets[i_row+1], SCREEN_COLUMNS);
428
14
        if (CHECK_FLAG(screen->row_used, i_row + 1))
429
7
            SET_FLAG(screen->row_used, i_row);
430
    }
431
432
9
    UNSET_FLAG(screen->row_used, ctx->cursor_row);
433
}
434
435
233
static int capture_screen(CCaptionSubContext *ctx)
436
{
437
233
    int i, j, tab = 0;
438
233
    struct Screen *screen = ctx->screen + ctx->active_screen;
439
233
    enum cc_font prev_font = CCFONT_REGULAR;
440
233
    av_bprint_clear(&ctx->buffer);
441
442

2138
    for (i = 0; screen->row_used && i < SCREEN_ROWS; i++)
443
    {
444
1905
        if (CHECK_FLAG(screen->row_used, i)) {
445
242
            const char *row = screen->characters[i];
446
242
            const char *charset = screen->charsets[i];
447
242
            j = 0;
448

1406
            while (row[j] == ' ' && charset[j] == CCSET_BASIC_AMERICAN)
449
1164
                j++;
450

242
            if (!tab || j < tab)
451
190
                tab = j;
452
        }
453
    }
454
455

2138
    for (i = 0; screen->row_used && i < SCREEN_ROWS; i++)
456
    {
457
1905
        if (CHECK_FLAG(screen->row_used, i)) {
458
242
            const char *row = screen->characters[i];
459
242
            const char *font = screen->fonts[i];
460
242
            const char *charset = screen->charsets[i];
461
            const char *override;
462
242
            int x, y, seen_char = 0;
463
242
            j = 0;
464
465
            /* skip leading space */
466

1213
            while (row[j] == ' ' && charset[j] == CCSET_BASIC_AMERICAN && j < tab)
467
971
                j++;
468
469
242
            x = ASS_DEFAULT_PLAYRESX * (0.1 + 0.0250 * j);
470
242
            y = ASS_DEFAULT_PLAYRESY * (0.1 + 0.0533 * i);
471
242
            av_bprintf(&ctx->buffer, "{\\an7}{\\pos(%d,%d)}", x, y);
472
473
4390
            for (; j < SCREEN_COLUMNS; j++) {
474
4383
                const char *e_tag = "", *s_tag = "";
475
476
4383
                if (row[j] == 0)
477
235
                    break;
478
479
4148
                if (prev_font != font[j]) {
480

74
                    switch (prev_font) {
481
22
                    case CCFONT_ITALICS:
482
22
                        e_tag = "{\\i0}";
483
22
                        break;
484
                    case CCFONT_UNDERLINED:
485
                        e_tag = "{\\u0}";
486
                        break;
487
                    case CCFONT_UNDERLINED_ITALICS:
488
                        e_tag = "{\\u0}{\\i0}";
489
                        break;
490
                    }
491

74
                    switch (font[j]) {
492
52
                    case CCFONT_ITALICS:
493
52
                        s_tag = "{\\i1}";
494
52
                        break;
495
                    case CCFONT_UNDERLINED:
496
                        s_tag = "{\\u1}";
497
                        break;
498
                    case CCFONT_UNDERLINED_ITALICS:
499
                        s_tag = "{\\u1}{\\i1}";
500
                        break;
501
                    }
502
4074
                }
503
4148
                prev_font = font[j];
504
4148
                override = charset_overrides[(int)charset[j]][(int)row[j]];
505
4148
                if (override) {
506
11
                    av_bprintf(&ctx->buffer, "%s%s%s", e_tag, s_tag, override);
507
11
                    seen_char = 1;
508

4137
                } else if (row[j] == ' ' && !seen_char) {
509
193
                    av_bprintf(&ctx->buffer, "%s%s\\h", e_tag, s_tag);
510
                } else {
511
3944
                    av_bprintf(&ctx->buffer, "%s%s%c", e_tag, s_tag, row[j]);
512
3944
                    seen_char = 1;
513
                }
514
515
            }
516
242
            av_bprintf(&ctx->buffer, "\\N");
517
        }
518
    }
519
233
    if (!av_bprint_is_complete(&ctx->buffer))
520
        return AVERROR(ENOMEM);
521

233
    if (screen->row_used && ctx->buffer.len >= 2) {
522
127
        ctx->buffer.len -= 2;
523
127
        ctx->buffer.str[ctx->buffer.len] = 0;
524
    }
525
233
    ctx->buffer_changed = 1;
526
233
    return 0;
527
}
528
529
203
static int reap_screen(CCaptionSubContext *ctx, int64_t pts)
530
{
531
203
    ctx->start_time = ctx->startv_time;
532
203
    ctx->startv_time = pts;
533
203
    ctx->end_time = pts;
534
203
    return capture_screen(ctx);
535
}
536
537
11
static void handle_textattr(CCaptionSubContext *ctx, uint8_t hi, uint8_t lo)
538
{
539
11
    int i = lo - 0x20;
540
11
    struct Screen *screen = get_writing_screen(ctx);
541
542
11
    if (i >= 32)
543
        return;
544
545
11
    ctx->cursor_color = pac2_attribs[i][0];
546
11
    ctx->cursor_font = pac2_attribs[i][1];
547
548
11
    SET_FLAG(screen->row_used, ctx->cursor_row);
549
11
    write_char(ctx, screen, ' ');
550
}
551
552
197
static void handle_pac(CCaptionSubContext *ctx, uint8_t hi, uint8_t lo)
553
{
554
    static const int8_t row_map[] = {
555
        11, -1, 1, 2, 3, 4, 12, 13, 14, 15, 5, 6, 7, 8, 9, 10
556
    };
557
197
    const int index = ( (hi<<1) & 0x0e) | ( (lo>>5) & 0x01 );
558
197
    struct Screen *screen = get_writing_screen(ctx);
559
    int indent, i;
560
561
197
    if (row_map[index] <= 0) {
562
        av_log(ctx, AV_LOG_DEBUG, "Invalid pac index encountered\n");
563
        return;
564
    }
565
566
197
    lo &= 0x1f;
567
568
197
    ctx->cursor_row = row_map[index] - 1;
569
197
    ctx->cursor_color =  pac2_attribs[lo][0];
570
197
    ctx->cursor_font = pac2_attribs[lo][1];
571
197
    ctx->cursor_charset = CCSET_BASIC_AMERICAN;
572
197
    ctx->cursor_column = 0;
573
197
    indent = pac2_attribs[lo][2];
574
1333
    for (i = 0; i < indent; i++) {
575
1136
        write_char(ctx, screen, ' ');
576
    }
577
}
578
579
/**
580
 * @param pts it is required to set end time
581
 */
582
197
static void handle_edm(CCaptionSubContext *ctx, int64_t pts)
583
{
584
197
    struct Screen *screen = ctx->screen + ctx->active_screen;
585
586
    // In buffered mode, keep writing to screen until it is wiped.
587
    // Before wiping the display, capture contents to emit subtitle.
588
197
    if (!ctx->real_time)
589
197
        reap_screen(ctx, pts);
590
591
197
    screen->row_used = 0;
592
593
    // In realtime mode, emit an empty caption so the last one doesn't
594
    // stay on the screen.
595
197
    if (ctx->real_time)
596
        reap_screen(ctx, pts);
597
197
}
598
599
93
static void handle_eoc(CCaptionSubContext *ctx, int64_t pts)
600
{
601
    // In buffered mode, we wait til the *next* EOC and
602
    // reap what was already on the screen since the last EOC.
603
93
    if (!ctx->real_time)
604
93
        handle_edm(ctx,pts);
605
606
93
    ctx->active_screen = !ctx->active_screen;
607
93
    ctx->cursor_column = 0;
608
609
    // In realtime mode, we display the buffered contents (after
610
    // flipping the buffer to active above) as soon as EOC arrives.
611
93
    if (ctx->real_time)
612
        reap_screen(ctx, pts);
613
93
}
614
615
static void handle_delete_end_of_row(CCaptionSubContext *ctx, char hi, char lo)
616
{
617
    struct Screen *screen = get_writing_screen(ctx);
618
    write_char(ctx, screen, 0);
619
}
620
621
1594
static void handle_char(CCaptionSubContext *ctx, char hi, char lo, int64_t pts)
622
{
623
1594
    struct Screen *screen = get_writing_screen(ctx);
624
625
1594
    SET_FLAG(screen->row_used, ctx->cursor_row);
626
627

1594
    switch (hi) {
628
      case 0x11:
629
        ctx->cursor_charset = CCSET_SPECIAL_AMERICAN;
630
        break;
631
      case 0x12:
632
        if (ctx->cursor_column > 0)
633
            ctx->cursor_column -= 1;
634
        ctx->cursor_charset = CCSET_EXTENDED_SPANISH_FRENCH_MISC;
635
        break;
636
      case 0x13:
637
        if (ctx->cursor_column > 0)
638
            ctx->cursor_column -= 1;
639
        ctx->cursor_charset = CCSET_EXTENDED_PORTUGUESE_GERMAN_DANISH;
640
        break;
641
1594
      default:
642
1594
        ctx->cursor_charset = CCSET_BASIC_AMERICAN;
643
1594
        write_char(ctx, screen, hi);
644
1594
        break;
645
    }
646
647
1594
    if (lo) {
648
1480
        write_char(ctx, screen, lo);
649
    }
650
1594
    write_char(ctx, screen, 0);
651
652
1594
    if (ctx->mode != CCMODE_POPON)
653
113
        ctx->screen_touched = 1;
654
655
    if (lo)
656
       ff_dlog(ctx, "(%c,%c)\n", hi, lo);
657
    else
658
       ff_dlog(ctx, "(%c)\n", hi);
659
1594
}
660
661
2757
static void process_cc608(CCaptionSubContext *ctx, int64_t pts, uint8_t hi, uint8_t lo)
662
{
663

2757
    if (hi == ctx->prev_cmd[0] && lo == ctx->prev_cmd[1]) {
664
        /* ignore redundant command */
665
648
        return;
666
    }
667
668
    /* set prev command */
669
2109
    ctx->prev_cmd[0] = hi;
670
2109
    ctx->prev_cmd[1] = lo;
671
672


2109
    if ( (hi == 0x10 && (lo >= 0x40 && lo <= 0x5f)) ||
673

2109
       ( (hi >= 0x11 && hi <= 0x17) && (lo >= 0x40 && lo <= 0x7f) ) ) {
674
197
        handle_pac(ctx, hi, lo);
675


1912
    } else if ( ( hi == 0x11 && lo >= 0x20 && lo <= 0x2f ) ||
676
                ( hi == 0x17 && lo >= 0x2e && lo <= 0x2f) ) {
677
11
        handle_textattr(ctx, hi, lo);
678

1901
    } else if (hi == 0x14 || hi == 0x15 || hi == 0x1c) {
679


307
        switch (lo) {
680
92
        case 0x20:
681
            /* resume caption loading */
682
92
            ctx->mode = CCMODE_POPON;
683
92
            break;
684
        case 0x24:
685
            handle_delete_end_of_row(ctx, hi, lo);
686
            break;
687
9
        case 0x25:
688
        case 0x26:
689
        case 0x27:
690
9
            ctx->rollup = lo - 0x23;
691
9
            ctx->mode = CCMODE_ROLLUP;
692
9
            break;
693
        case 0x29:
694
            /* resume direct captioning */
695
            ctx->mode = CCMODE_PAINTON;
696
            break;
697
        case 0x2b:
698
            /* resume text display */
699
            ctx->mode = CCMODE_TEXT;
700
            break;
701
104
        case 0x2c:
702
            /* erase display memory */
703
104
            handle_edm(ctx, pts);
704
104
            break;
705
9
        case 0x2d:
706
            /* carriage return */
707
            ff_dlog(ctx, "carriage return\n");
708
9
            if (!ctx->real_time)
709
6
                reap_screen(ctx, pts);
710
9
            roll_up(ctx);
711
9
            ctx->cursor_column = 0;
712
9
            break;
713
        case 0x2e:
714
            /* erase buffered (non displayed) memory */
715
            // Only in realtime mode. In buffered mode, we re-use the inactive screen
716
            // for our own buffering.
717
            if (ctx->real_time) {
718
                struct Screen *screen = ctx->screen + !ctx->active_screen;
719
                screen->row_used = 0;
720
            }
721
            break;
722
93
        case 0x2f:
723
            /* end of caption */
724
            ff_dlog(ctx, "handle_eoc\n");
725
93
            handle_eoc(ctx, pts);
726
93
            break;
727
        default:
728
            ff_dlog(ctx, "Unknown command 0x%hhx 0x%hhx\n", hi, lo);
729
            break;
730
        }
731

1594
    } else if (hi >= 0x11 && hi <= 0x13) {
732
        /* Special characters */
733
        handle_char(ctx, hi, lo, pts);
734
1594
    } else if (hi >= 0x20) {
735
        /* Standard characters (always in pairs) */
736
1594
        handle_char(ctx, hi, lo, pts);
737
1594
        ctx->prev_cmd[0] = ctx->prev_cmd[1] = 0;
738
    } else if (hi == 0x17 && lo >= 0x21 && lo <= 0x23) {
739
        int i;
740
        /* Tab offsets (spacing) */
741
        for (i = 0; i < lo - 0x20; i++) {
742
            handle_char(ctx, ' ', 0, pts);
743
        }
744
    } else {
745
        /* Ignoring all other non data code */
746
        ff_dlog(ctx, "Unknown command 0x%hhx 0x%hhx\n", hi, lo);
747
    }
748
}
749
750
576
static int decode(AVCodecContext *avctx, void *data, int *got_sub, AVPacket *avpkt)
751
{
752
576
    CCaptionSubContext *ctx = avctx->priv_data;
753
576
    AVSubtitle *sub = data;
754
576
    const int64_t start_time = sub->pts;
755
576
    uint8_t *bptr = NULL;
756
576
    int len = avpkt->size;
757
576
    int ret = 0;
758
    int i;
759
760
576
    av_fast_padded_malloc(&ctx->pktbuf, &ctx->pktbuf_size, len);
761
576
    if (!ctx->pktbuf) {
762
        av_log(ctx, AV_LOG_WARNING, "Insufficient Memory of %d truncated to %d\n", len, ctx->pktbuf_size);
763
        return AVERROR(ENOMEM);
764
    }
765
576
    memcpy(ctx->pktbuf, avpkt->data, len);
766
576
    bptr = ctx->pktbuf;
767
768
8829
    for (i  = 0; i < len; i += 3) {
769
8253
        uint8_t cc_type = *(bptr + i) & 3;
770
8253
        if (validate_cc_data_pair(bptr + i))
771
5294
            continue;
772
        /* ignoring data field 1 */
773
2959
        if(cc_type == 1)
774
202
            continue;
775
        else
776
2757
            process_cc608(ctx, start_time, *(bptr + i + 1) & 0x7f, *(bptr + i + 2) & 0x7f);
777
778
2757
        if (!ctx->buffer_changed)
779
2554
            continue;
780
203
        ctx->buffer_changed = 0;
781
782

203
        if (*ctx->buffer.str || ctx->real_time)
783
        {
784
            ff_dlog(ctx, "cdp writing data (%s)\n",ctx->buffer.str);
785
97
            ret = ff_ass_add_rect(sub, ctx->buffer.str, ctx->readorder++, 0, NULL, NULL);
786
97
            if (ret < 0)
787
                return ret;
788
97
            sub->pts = ctx->start_time;
789
97
            if (!ctx->real_time)
790
97
                sub->end_display_time = av_rescale_q(ctx->end_time - ctx->start_time,
791
97
                                                     AV_TIME_BASE_Q, ms_tb);
792
            else
793
                sub->end_display_time = -1;
794
97
            ctx->buffer_changed = 0;
795
97
            ctx->last_real_time = sub->pts;
796
97
            ctx->screen_touched = 0;
797
        }
798
    }
799
800

576
    if (ctx->real_time && ctx->screen_touched &&
801
31
        sub->pts > ctx->last_real_time + av_rescale_q(200, ms_tb, AV_TIME_BASE_Q)) {
802
30
        ctx->last_real_time = sub->pts;
803
30
        ctx->screen_touched = 0;
804
805
30
        capture_screen(ctx);
806
30
        ctx->buffer_changed = 0;
807
808
30
        ret = ff_ass_add_rect(sub, ctx->buffer.str, ctx->readorder++, 0, NULL, NULL);
809
30
        if (ret < 0)
810
            return ret;
811
30
        sub->end_display_time = -1;
812
    }
813
814
576
    *got_sub = sub->num_rects > 0;
815
576
    return ret;
816
}
817
818
#define OFFSET(x) offsetof(CCaptionSubContext, x)
819
#define SD AV_OPT_FLAG_SUBTITLE_PARAM | AV_OPT_FLAG_DECODING_PARAM
820
static const AVOption options[] = {
821
    { "real_time", "emit subtitle events as they are decoded for real-time display", OFFSET(real_time), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, SD },
822
    {NULL}
823
};
824
825
static const AVClass ccaption_dec_class = {
826
    .class_name = "Closed caption Decoder",
827
    .item_name  = av_default_item_name,
828
    .option     = options,
829
    .version    = LIBAVUTIL_VERSION_INT,
830
};
831
832
AVCodec ff_ccaption_decoder = {
833
    .name           = "cc_dec",
834
    .long_name      = NULL_IF_CONFIG_SMALL("Closed Caption (EIA-608 / CEA-708)"),
835
    .type           = AVMEDIA_TYPE_SUBTITLE,
836
    .id             = AV_CODEC_ID_EIA_608,
837
    .priv_data_size = sizeof(CCaptionSubContext),
838
    .init           = init_decoder,
839
    .close          = close_decoder,
840
    .flush          = flush_decoder,
841
    .decode         = decode,
842
    .priv_class     = &ccaption_dec_class,
843
};