FFmpeg coverage

Directory: ../../../ffmpeg/
File: src/libavcodec/pgssubdec.c
Date: 2026-01-16 07:34:38
Exec Total Coverage
Lines: 198 272 72.8%
Functions: 11 11 100.0%
Branches: 81 150 54.0%
Line Branch Exec Source
1 /*
2 * PGS subtitle decoder
3 * Copyright (c) 2009 Stephen Backway
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 /**
23 * @file
24 * PGS subtitle decoder
25 */
26
27 #include "avcodec.h"
28 #include "bytestream.h"
29 #include "codec_internal.h"
30 #include "decode.h"
31 #include "mathops.h"
32
33 #include "libavutil/colorspace.h"
34 #include "libavutil/mem.h"
35 #include "libavutil/opt.h"
36
37 #define RGBA(r,g,b,a) (((unsigned)(a) << 24) | ((r) << 16) | ((g) << 8) | (b))
38 #define MAX_EPOCH_PALETTES 8 // Max 8 allowed per PGS epoch
39 #define MAX_EPOCH_OBJECTS 64 // Max 64 allowed per PGS epoch
40 #define MAX_OBJECT_REFS 2 // Max objects per display set
41
42 enum SegmentType {
43 PALETTE_SEGMENT = 0x14,
44 OBJECT_SEGMENT = 0x15,
45 PRESENTATION_SEGMENT = 0x16,
46 WINDOW_SEGMENT = 0x17,
47 DISPLAY_SEGMENT = 0x80,
48 };
49
50 typedef struct PGSSubObjectRef {
51 int id;
52 int window_id;
53 uint8_t composition_flag;
54 int x;
55 int y;
56 int crop_x;
57 int crop_y;
58 int crop_w;
59 int crop_h;
60 } PGSSubObjectRef;
61
62 typedef struct PGSSubPresentation {
63 int id_number;
64 int palette_id;
65 int object_count;
66 PGSSubObjectRef objects[MAX_OBJECT_REFS];
67 int64_t pts;
68 } PGSSubPresentation;
69
70 typedef struct PGSSubObject {
71 int id;
72 int w;
73 int h;
74 uint8_t *rle;
75 unsigned int rle_buffer_size, rle_data_len;
76 unsigned int rle_remaining_len;
77 } PGSSubObject;
78
79 typedef struct PGSSubObjects {
80 int count;
81 PGSSubObject object[MAX_EPOCH_OBJECTS];
82 } PGSSubObjects;
83
84 typedef struct PGSSubPalette {
85 int id;
86 uint32_t clut[256];
87 } PGSSubPalette;
88
89 typedef struct PGSSubPalettes {
90 int count;
91 PGSSubPalette palette[MAX_EPOCH_PALETTES];
92 } PGSSubPalettes;
93
94 typedef struct PGSSubContext {
95 AVClass *class;
96 PGSSubPresentation presentation;
97 PGSSubPalettes palettes;
98 PGSSubObjects objects;
99 int forced_subs_only;
100 } PGSSubContext;
101
102 17 static void flush_cache(AVCodecContext *avctx)
103 {
104 17 PGSSubContext *ctx = avctx->priv_data;
105 int i;
106
107
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 24 for (i = 0; i < ctx->objects.count; i++) {
108 7 av_freep(&ctx->objects.object[i].rle);
109 7 ctx->objects.object[i].rle_buffer_size = 0;
110 7 ctx->objects.object[i].rle_remaining_len = 0;
111 }
112 17 ctx->objects.count = 0;
113 17 ctx->palettes.count = 0;
114 17 }
115
116 13 static PGSSubObject * find_object(int id, PGSSubObjects *objects)
117 {
118 int i;
119
120
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 19 for (i = 0; i < objects->count; i++) {
121
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 12 if (objects->object[i].id == id)
122 6 return &objects->object[i];
123 }
124 7 return NULL;
125 }
126
127 7 static PGSSubPalette * find_palette(int id, PGSSubPalettes *palettes)
128 {
129 int i;
130
131
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 7 for (i = 0; i < palettes->count; i++) {
132
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 3 if (palettes->palette[i].id == id)
133 3 return &palettes->palette[i];
134 }
135 4 return NULL;
136 }
137
138 8 static av_cold int init_decoder(AVCodecContext *avctx)
139 {
140 8 avctx->pix_fmt = AV_PIX_FMT_PAL8;
141
142 8 return 0;
143 }
144
145 8 static av_cold int close_decoder(AVCodecContext *avctx)
146 {
147 8 flush_cache(avctx);
148
149 8 return 0;
150 }
151
152 /**
153 * Decode the RLE data.
154 *
155 * The subtitle is stored as a Run Length Encoded image.
156 *
157 * @param avctx contains the current codec context
158 * @param sub pointer to the processed subtitle data
159 * @param buf pointer to the RLE data to process
160 * @param buf_size size of the RLE data to process
161 */
162 6 static int decode_rle(AVCodecContext *avctx, AVSubtitleRect *rect,
163 const uint8_t *buf, unsigned int buf_size)
164 {
165 const uint8_t *rle_bitmap_end;
166 int pixel_count, line_count;
167
168 6 rle_bitmap_end = buf + buf_size;
169
170 6 rect->data[0] = av_malloc_array(rect->w, rect->h);
171
172
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 6 if (!rect->data[0])
173 ✗ return AVERROR(ENOMEM);
174
175 6 pixel_count = 0;
176 6 line_count = 0;
177
178
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 47187 while (buf < rle_bitmap_end && line_count < rect->h) {
179 uint8_t flags, color;
180 int run;
181
182 47181 color = bytestream_get_byte(&buf);
183 47181 run = 1;
184
185
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 47181 if (color == 0x00) {
186 17154 flags = bytestream_get_byte(&buf);
187 17154 run = flags & 0x3f;
188
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 17154 if (flags & 0x40)
189 762 run = (run << 8) + bytestream_get_byte(&buf);
190
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 17154 color = flags & 0x80 ? bytestream_get_byte(&buf) : 0;
191 }
192
193
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 47181 if (run > 0 && pixel_count + run <= rect->w * rect->h) {
194 46791 memset(rect->data[0] + pixel_count, color, run);
195 46791 pixel_count += run;
196
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 390 } else if (!run) {
197 /*
198 * New Line. Check if correct pixels decoded, if not display warning
199 * and adjust bitmap pointer to correct new line position.
200 */
201
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 390 if (pixel_count % rect->w > 0) {
202 ✗ av_log(avctx, AV_LOG_ERROR, "Decoded %d pixels, when line should be %d pixels\n",
203 ✗ pixel_count % rect->w, rect->w);
204 ✗ if (avctx->err_recognition & AV_EF_EXPLODE) {
205 ✗ return AVERROR_INVALIDDATA;
206 }
207 }
208 390 line_count++;
209 }
210 }
211
212
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 6 if (pixel_count < rect->w * rect->h) {
213 ✗ av_log(avctx, AV_LOG_ERROR, "Insufficient RLE data for subtitle\n");
214 ✗ return AVERROR_INVALIDDATA;
215 }
216
217 ff_dlog(avctx, "Pixel Count = %d, Area = %d\n", pixel_count, rect->w * rect->h);
218
219 6 return 0;
220 }
221
222 /**
223 * Parse the picture segment packet.
224 *
225 * The picture segment contains details on the sequence id,
226 * width, height and Run Length Encoded (RLE) bitmap data.
227 *
228 * @param avctx contains the current codec context
229 * @param buf pointer to the packet to process
230 * @param buf_size size of packet to process
231 */
232 7 static int parse_object_segment(AVCodecContext *avctx,
233 const uint8_t *buf, int buf_size)
234 {
235 7 PGSSubContext *ctx = avctx->priv_data;
236 PGSSubObject *object;
237
238 uint8_t sequence_desc;
239 unsigned int rle_bitmap_len, width, height;
240 int id;
241
242
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 7 if (buf_size <= 4)
243 ✗ return AVERROR_INVALIDDATA;
244 7 buf_size -= 4;
245
246 7 id = bytestream_get_be16(&buf);
247 7 object = find_object(id, &ctx->objects);
248
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 7 if (!object) {
249
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 7 if (ctx->objects.count >= MAX_EPOCH_OBJECTS) {
250 ✗ av_log(avctx, AV_LOG_ERROR, "Too many objects in epoch\n");
251 ✗ return AVERROR_INVALIDDATA;
252 }
253 7 object = &ctx->objects.object[ctx->objects.count++];
254 7 object->id = id;
255 }
256
257 /* skip object version number */
258 7 buf += 1;
259
260 /* Read the Sequence Description to determine if start of RLE data or appended to previous RLE */
261 7 sequence_desc = bytestream_get_byte(&buf);
262
263
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 7 if (!(sequence_desc & 0x80)) {
264 /* Additional RLE data */
265 ✗ if (buf_size > object->rle_remaining_len)
266 ✗ return AVERROR_INVALIDDATA;
267
268 ✗ memcpy(object->rle + object->rle_data_len, buf, buf_size);
269 ✗ object->rle_data_len += buf_size;
270 ✗ object->rle_remaining_len -= buf_size;
271
272 ✗ return 0;
273 }
274
275
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 7 if (buf_size <= 7)
276 ✗ return AVERROR_INVALIDDATA;
277 7 buf_size -= 7;
278
279 /* Decode rle bitmap length, stored size includes width/height data */
280 7 rle_bitmap_len = bytestream_get_be24(&buf) - 2*2;
281
282
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 7 if (buf_size > rle_bitmap_len) {
283 ✗ av_log(avctx, AV_LOG_ERROR,
284 "Buffer dimension %d larger than the expected RLE data %d\n",
285 buf_size, rle_bitmap_len);
286 ✗ return AVERROR_INVALIDDATA;
287 }
288
289 /* Get bitmap dimensions from data */
290 7 width = bytestream_get_be16(&buf);
291 7 height = bytestream_get_be16(&buf);
292
293 /* Make sure the bitmap is not too large */
294
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 7 if (avctx->width < width || avctx->height < height || !width || !height) {
295 ✗ av_log(avctx, AV_LOG_ERROR, "Bitmap dimensions (%dx%d) invalid.\n", width, height);
296 ✗ return AVERROR_INVALIDDATA;
297 }
298
299 7 object->w = width;
300 7 object->h = height;
301
302 7 av_fast_padded_malloc(&object->rle, &object->rle_buffer_size, rle_bitmap_len);
303
304
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 7 if (!object->rle) {
305 ✗ object->rle_data_len = 0;
306 ✗ object->rle_remaining_len = 0;
307 ✗ return AVERROR(ENOMEM);
308 }
309
310 7 memcpy(object->rle, buf, buf_size);
311 7 object->rle_data_len = buf_size;
312 7 object->rle_remaining_len = rle_bitmap_len - buf_size;
313
314 7 return 0;
315 }
316
317 /**
318 * Parse the palette segment packet.
319 *
320 * The palette segment contains details of the palette,
321 * a maximum of 256 colors can be defined.
322 *
323 * @param avctx contains the current codec context
324 * @param buf pointer to the packet to process
325 * @param buf_size size of packet to process
326 */
327 4 static int parse_palette_segment(AVCodecContext *avctx,
328 const uint8_t *buf, int buf_size)
329 {
330 4 PGSSubContext *ctx = avctx->priv_data;
331 PGSSubPalette *palette;
332
333 4 const uint8_t *buf_end = buf + buf_size;
334 4 const uint8_t *cm = ff_crop_tab + MAX_NEG_CROP;
335 int color_id;
336 int y, cb, cr, alpha;
337 int r, g, b, r_add, g_add, b_add;
338 int id;
339
340 4 id = bytestream_get_byte(&buf);
341 4 palette = find_palette(id, &ctx->palettes);
342
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 4 if (!palette) {
343
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 4 if (ctx->palettes.count >= MAX_EPOCH_PALETTES) {
344 ✗ av_log(avctx, AV_LOG_ERROR, "Too many palettes in epoch\n");
345 ✗ return AVERROR_INVALIDDATA;
346 }
347 4 palette = &ctx->palettes.palette[ctx->palettes.count++];
348 4 palette->id = id;
349 }
350
351 /* Skip palette version */
352 4 buf += 1;
353
354
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 128 while (buf < buf_end) {
355 124 color_id = bytestream_get_byte(&buf);
356 124 y = bytestream_get_byte(&buf);
357 124 cr = bytestream_get_byte(&buf);
358 124 cb = bytestream_get_byte(&buf);
359 124 alpha = bytestream_get_byte(&buf);
360
361 /* Default to BT.709 colorspace. In case of <= 576 height use BT.601 */
362
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 124 if (avctx->height <= 0 || avctx->height > 576) {
363 124 YUV_TO_RGB1_CCIR_BT709(cb, cr);
364 } else {
365 ✗ YUV_TO_RGB1_CCIR(cb, cr);
366 }
367
368 124 YUV_TO_RGB2_CCIR(r, g, b, y);
369
370 ff_dlog(avctx, "Color %d := (%d,%d,%d,%d)\n", color_id, r, g, b, alpha);
371
372 /* Store color in palette */
373 124 palette->clut[color_id] = RGBA(r,g,b,alpha);
374 }
375 4 return 0;
376 }
377
378 /**
379 * Parse the presentation segment packet.
380 *
381 * The presentation segment contains details on the video
382 * width, video height, x & y subtitle position.
383 *
384 * @param avctx contains the current codec context
385 * @param buf pointer to the packet to process
386 * @param buf_size size of packet to process
387 * @todo TODO: Implement cropping
388 */
389 9 static int parse_presentation_segment(AVCodecContext *avctx,
390 const uint8_t *buf, int buf_size,
391 int64_t pts)
392 {
393 9 PGSSubContext *ctx = avctx->priv_data;
394 int i, state, ret;
395 9 const uint8_t *buf_end = buf + buf_size;
396
397 // Video descriptor
398 9 int w = bytestream_get_be16(&buf);
399 9 int h = bytestream_get_be16(&buf);
400
401 9 ctx->presentation.pts = pts;
402
403 ff_dlog(avctx, "Video Dimensions %dx%d\n",
404 w, h);
405 9 ret = ff_set_dimensions(avctx, w, h);
406
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 9 if (ret < 0)
407 ✗ return ret;
408
409 /* Skip 1 bytes of unknown, frame rate */
410 9 buf++;
411
412 // Composition descriptor
413 9 ctx->presentation.id_number = bytestream_get_be16(&buf);
414 /*
415 * state is a 2 bit field that defines pgs epoch boundaries
416 * 00 - Normal, previously defined objects and palettes are still valid
417 * 01 - Acquisition point, previous objects and palettes can be released
418 * 10 - Epoch start, previous objects and palettes can be released
419 * 11 - Epoch continue, previous objects and palettes can be released
420 *
421 * reserved 6 bits discarded
422 */
423 9 state = bytestream_get_byte(&buf) >> 6;
424
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 9 if (state != 0) {
425 9 flush_cache(avctx);
426 }
427
428 /*
429 * skip palette_update_flag (0x80),
430 */
431 9 buf += 1;
432 9 ctx->presentation.palette_id = bytestream_get_byte(&buf);
433 9 ctx->presentation.object_count = bytestream_get_byte(&buf);
434
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 9 if (ctx->presentation.object_count > MAX_OBJECT_REFS) {
435 ✗ av_log(avctx, AV_LOG_ERROR,
436 "Invalid number of presentation objects %d\n",
437 ctx->presentation.object_count);
438 ✗ ctx->presentation.object_count = 2;
439 ✗ if (avctx->err_recognition & AV_EF_EXPLODE) {
440 ✗ return AVERROR_INVALIDDATA;
441 }
442 }
443
444
445
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 27 for (i = 0; i < ctx->presentation.object_count; i++)
446 {
447 18 PGSSubObjectRef *const object = &ctx->presentation.objects[i];
448
449
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 18 if (buf_end - buf < 8) {
450 ✗ av_log(avctx, AV_LOG_ERROR, "Insufficient space for object\n");
451 ✗ ctx->presentation.object_count = i;
452 ✗ return AVERROR_INVALIDDATA;
453 }
454
455 18 object->id = bytestream_get_be16(&buf);
456 18 object->window_id = bytestream_get_byte(&buf);
457 18 object->composition_flag = bytestream_get_byte(&buf);
458
459 18 object->x = bytestream_get_be16(&buf);
460 18 object->y = bytestream_get_be16(&buf);
461
462 // If cropping
463
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 18 if (object->composition_flag & 0x80) {
464 ✗ object->crop_x = bytestream_get_be16(&buf);
465 ✗ object->crop_y = bytestream_get_be16(&buf);
466 ✗ object->crop_w = bytestream_get_be16(&buf);
467 ✗ object->crop_h = bytestream_get_be16(&buf);
468 }
469
470 ff_dlog(avctx, "Subtitle Placement x=%d, y=%d\n",
471 object->x, object->y);
472
473
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 18 if (object->x > avctx->width || object->y > avctx->height) {
474 ✗ av_log(avctx, AV_LOG_ERROR, "Subtitle out of video bounds. x = %d, y = %d, video width = %d, video height = %d.\n",
475 object->x, object->y,
476 avctx->width, avctx->height);
477 ✗ object->y = object->x = 0;
478 ✗ if (avctx->err_recognition & AV_EF_EXPLODE) {
479 ✗ return AVERROR_INVALIDDATA;
480 }
481 }
482 }
483
484 9 return 0;
485 }
486
487 /**
488 * Parse the display segment packet.
489 *
490 * The display segment controls the updating of the display.
491 *
492 * @param avctx contains the current codec context
493 * @param data pointer to the data pertaining the subtitle to display
494 * @param buf pointer to the packet to process
495 * @param buf_size size of packet to process
496 */
497 3 static int display_end_segment(AVCodecContext *avctx, AVSubtitle *sub,
498 const uint8_t *buf, int buf_size)
499 {
500 3 PGSSubContext *ctx = avctx->priv_data;
501 int64_t pts;
502 PGSSubPalette *palette;
503 int i, ret;
504
505
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 3 pts = ctx->presentation.pts != AV_NOPTS_VALUE ? ctx->presentation.pts : sub->pts;
506 3 memset(sub, 0, sizeof(*sub));
507 3 sub->pts = pts;
508 3 ctx->presentation.pts = AV_NOPTS_VALUE;
509 3 sub->start_display_time = 0;
510 // There is no explicit end time for PGS subtitles. The end time
511 // is defined by the start of the next sub which may contain no
512 // objects (i.e. clears the previous sub)
513 3 sub->end_display_time = UINT32_MAX;
514 3 sub->format = 0;
515
516 // Blank if last object_count was 0.
517
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 3 if (!ctx->presentation.object_count)
518 ✗ return 1;
519 3 sub->rects = av_calloc(ctx->presentation.object_count, sizeof(*sub->rects));
520
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 3 if (!sub->rects) {
521 ✗ return AVERROR(ENOMEM);
522 }
523 3 palette = find_palette(ctx->presentation.palette_id, &ctx->palettes);
524
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 3 if (!palette) {
525 // Missing palette. Should only happen with damaged streams.
526 ✗ av_log(avctx, AV_LOG_ERROR, "Invalid palette id %d\n",
527 ctx->presentation.palette_id);
528 ✗ avsubtitle_free(sub);
529 ✗ return AVERROR_INVALIDDATA;
530 }
531
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 9 for (i = 0; i < ctx->presentation.object_count; i++) {
532 6 AVSubtitleRect *const rect = av_mallocz(sizeof(*rect));
533 PGSSubObject *object;
534
535
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 6 if (!rect)
536 ✗ return AVERROR(ENOMEM);
537 6 sub->rects[sub->num_rects++] = rect;
538 6 rect->type = SUBTITLE_BITMAP;
539
540 /* Process bitmap */
541 6 object = find_object(ctx->presentation.objects[i].id, &ctx->objects);
542
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 6 if (!object) {
543 // Missing object. Should only happen with damaged streams.
544 ✗ av_log(avctx, AV_LOG_ERROR, "Invalid object id %d\n",
545 ctx->presentation.objects[i].id);
546 ✗ if (avctx->err_recognition & AV_EF_EXPLODE)
547 ✗ return AVERROR_INVALIDDATA;
548 // Leaves rect empty with 0 width and height.
549 ✗ continue;
550 }
551
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 6 if (ctx->presentation.objects[i].composition_flag & 0x40)
552 ✗ rect->flags |= AV_SUBTITLE_FLAG_FORCED;
553
554 6 rect->x = ctx->presentation.objects[i].x;
555 6 rect->y = ctx->presentation.objects[i].y;
556
557
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 6 if (object->rle) {
558 6 rect->w = object->w;
559 6 rect->h = object->h;
560
561 6 rect->linesize[0] = object->w;
562
563
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 6 if (object->rle_remaining_len) {
564 ✗ av_log(avctx, AV_LOG_ERROR, "RLE data length %u is %u bytes shorter than expected\n",
565 object->rle_data_len, object->rle_remaining_len);
566 ✗ if (avctx->err_recognition & AV_EF_EXPLODE)
567 ✗ return AVERROR_INVALIDDATA;
568 }
569 6 ret = decode_rle(avctx, rect, object->rle, object->rle_data_len);
570
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 6 if (ret < 0) {
571 ✗ if ((avctx->err_recognition & AV_EF_EXPLODE) ||
572 ret == AVERROR(ENOMEM)) {
573 ✗ return ret;
574 }
575 ✗ rect->w = 0;
576 ✗ rect->h = 0;
577 ✗ continue;
578 }
579 }
580 /* Allocate memory for colors */
581 6 rect->nb_colors = 256;
582 6 rect->data[1] = av_mallocz(AVPALETTE_SIZE);
583
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 6 if (!rect->data[1])
584 ✗ return AVERROR(ENOMEM);
585
586
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 6 if (!ctx->forced_subs_only || ctx->presentation.objects[i].composition_flag & 0x40)
587 6 memcpy(rect->data[1], palette->clut, rect->nb_colors * sizeof(uint32_t));
588 }
589 3 return 1;
590 }
591
592 17 static int decode(AVCodecContext *avctx, AVSubtitle *sub,
593 int *got_sub_ptr, const AVPacket *avpkt)
594 {
595 17 const uint8_t *buf = avpkt->data;
596 17 int buf_size = avpkt->size;
597
598 const uint8_t *buf_end;
599 uint8_t segment_type;
600 int segment_length;
601 int i, ret;
602
603 ff_dlog(avctx, "PGS sub packet:\n");
604
605
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 101703 for (i = 0; i < buf_size; i++) {
606 ff_dlog(avctx, "%02x ", buf[i]);
607 101686 if (i % 16 == 15)
608 ff_dlog(avctx, "\n");
609 }
610
611 17 if (i & 15)
612 ff_dlog(avctx, "\n");
613
614 17 *got_sub_ptr = 0;
615
616 /* Ensure that we have received at a least a segment code and segment length */
617
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 17 if (buf_size < 3)
618 ✗ return -1;
619
620 17 buf_end = buf + buf_size;
621
622 /* Step through buffer to identify segments */
623
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 44 while (buf < buf_end) {
624 27 segment_type = bytestream_get_byte(&buf);
625 27 segment_length = bytestream_get_be16(&buf);
626
627 ff_dlog(avctx, "Segment Length %d, Segment Type %x\n", segment_length, segment_type);
628
629
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 27 if (segment_type != DISPLAY_SEGMENT && segment_length > buf_end - buf)
630 ✗ break;
631
632 27 ret = 0;
633
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 27 switch (segment_type) {
634 4 case PALETTE_SEGMENT:
635 4 ret = parse_palette_segment(avctx, buf, segment_length);
636 4 break;
637 7 case OBJECT_SEGMENT:
638 7 ret = parse_object_segment(avctx, buf, segment_length);
639 7 break;
640 9 case PRESENTATION_SEGMENT:
641 9 ret = parse_presentation_segment(avctx, buf, segment_length, sub->pts);
642 9 break;
643 4 case WINDOW_SEGMENT:
644 /*
645 * Window Segment Structure (No new information provided):
646 * 2 bytes: Unknown,
647 * 2 bytes: X position of subtitle,
648 * 2 bytes: Y position of subtitle,
649 * 2 bytes: Width of subtitle,
650 * 2 bytes: Height of subtitle.
651 */
652 4 break;
653 3 case DISPLAY_SEGMENT:
654
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 3 if (*got_sub_ptr) {
655 ✗ av_log(avctx, AV_LOG_ERROR, "Duplicate display segment\n");
656 ✗ ret = AVERROR_INVALIDDATA;
657 ✗ break;
658 }
659 3 ret = display_end_segment(avctx, sub, buf, segment_length);
660
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 3 if (ret >= 0)
661 3 *got_sub_ptr = ret;
662 3 break;
663 ✗ default:
664 ✗ av_log(avctx, AV_LOG_ERROR, "Unknown subtitle segment type 0x%x, length %d\n",
665 segment_type, segment_length);
666 ✗ ret = AVERROR_INVALIDDATA;
667 ✗ break;
668 }
669
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 27 if (ret < 0 && (ret == AVERROR(ENOMEM) ||
670 ✗ avctx->err_recognition & AV_EF_EXPLODE))
671 ✗ return ret;
672
673 27 buf += segment_length;
674 }
675
676 17 return buf_size;
677 }
678
679 #define OFFSET(x) offsetof(PGSSubContext, x)
680 #define SD AV_OPT_FLAG_SUBTITLE_PARAM | AV_OPT_FLAG_DECODING_PARAM
681 static const AVOption options[] = {
682 {"forced_subs_only", "Only show forced subtitles", OFFSET(forced_subs_only), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, SD},
683 { NULL },
684 };
685
686 static const AVClass pgsdec_class = {
687 .class_name = "PGS subtitle decoder",
688 .item_name = av_default_item_name,
689 .option = options,
690 .version = LIBAVUTIL_VERSION_INT,
691 };
692
693 const FFCodec ff_pgssub_decoder = {
694 .p.name = "pgssub",
695 CODEC_LONG_NAME("HDMV Presentation Graphic Stream subtitles"),
696 .p.type = AVMEDIA_TYPE_SUBTITLE,
697 .p.id = AV_CODEC_ID_HDMV_PGS_SUBTITLE,
698 .priv_data_size = sizeof(PGSSubContext),
699 .init = init_decoder,
700 .close = close_decoder,
701 FF_CODEC_DECODE_SUB_CB(decode),
702 .p.priv_class = &pgsdec_class,
703 };
704