| 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 "internal.h" |
| 30 | #include "mathops.h" |
| 31 | |
| 32 | #include "libavutil/colorspace.h" |
| 33 | #include "libavutil/imgutils.h" |
| 34 | #include "libavutil/opt.h" |
| 35 | |
| 36 | #define RGBA(r,g,b,a) (((a) << 24) | ((r) << 16) | ((g) << 8) | (b)) |
| 37 | #define MAX_EPOCH_PALETTES 8 // Max 8 allowed per PGS epoch |
| 38 | #define MAX_EPOCH_OBJECTS 64 // Max 64 allowed per PGS epoch |
| 39 | #define MAX_OBJECT_REFS 2 // Max objects per display set |
| 40 | |
| 41 | enum SegmentType { |
| 42 | PALETTE_SEGMENT = 0x14, |
| 43 | OBJECT_SEGMENT = 0x15, |
| 44 | PRESENTATION_SEGMENT = 0x16, |
| 45 | WINDOW_SEGMENT = 0x17, |
| 46 | DISPLAY_SEGMENT = 0x80, |
| 47 | }; |
| 48 | |
| 49 | typedef struct PGSSubObjectRef { |
| 50 | int id; |
| 51 | int window_id; |
| 52 | uint8_t composition_flag; |
| 53 | int x; |
| 54 | int y; |
| 55 | int crop_x; |
| 56 | int crop_y; |
| 57 | int crop_w; |
| 58 | int crop_h; |
| 59 | } PGSSubObjectRef; |
| 60 | |
| 61 | typedef struct PGSSubPresentation { |
| 62 | int id_number; |
| 63 | int palette_id; |
| 64 | int object_count; |
| 65 | PGSSubObjectRef objects[MAX_OBJECT_REFS]; |
| 66 | int64_t pts; |
| 67 | } PGSSubPresentation; |
| 68 | |
| 69 | typedef struct PGSSubObject { |
| 70 | int id; |
| 71 | int w; |
| 72 | int h; |
| 73 | uint8_t *rle; |
| 74 | unsigned int rle_buffer_size, rle_data_len; |
| 75 | unsigned int rle_remaining_len; |
| 76 | } PGSSubObject; |
| 77 | |
| 78 | typedef struct PGSSubObjects { |
| 79 | int count; |
| 80 | PGSSubObject object[MAX_EPOCH_OBJECTS]; |
| 81 | } PGSSubObjects; |
| 82 | |
| 83 | typedef struct PGSSubPalette { |
| 84 | int id; |
| 85 | uint32_t clut[256]; |
| 86 | } PGSSubPalette; |
| 87 | |
| 88 | typedef struct PGSSubPalettes { |
| 89 | int count; |
| 90 | PGSSubPalette palette[MAX_EPOCH_PALETTES]; |
| 91 | } PGSSubPalettes; |
| 92 | |
| 93 | typedef struct PGSSubContext { |
| 94 | AVClass *class; |
| 95 | PGSSubPresentation presentation; |
| 96 | PGSSubPalettes palettes; |
| 97 | PGSSubObjects objects; |
| 98 | int forced_subs_only; |
| 99 | } PGSSubContext; |
| 100 | |
| 101 | static void flush_cache(AVCodecContext *avctx) |
| 102 | { |
| 103 | PGSSubContext *ctx = avctx->priv_data; |
| 104 | int i; |
| 105 | |
| 106 | for (i = 0; i < ctx->objects.count; i++) { |
| 107 | av_freep(&ctx->objects.object[i].rle); |
| 108 | ctx->objects.object[i].rle_buffer_size = 0; |
| 109 | ctx->objects.object[i].rle_remaining_len = 0; |
| 110 | } |
| 111 | ctx->objects.count = 0; |
| 112 | ctx->palettes.count = 0; |
| 113 | } |
| 114 | |
| 115 | static PGSSubObject * find_object(int id, PGSSubObjects *objects) |
| 116 | { |
| 117 | int i; |
| 118 | |
| 119 | for (i = 0; i < objects->count; i++) { |
| 120 | if (objects->object[i].id == id) |
| 121 | return &objects->object[i]; |
| 122 | } |
| 123 | return NULL; |
| 124 | } |
| 125 | |
| 126 | static PGSSubPalette * find_palette(int id, PGSSubPalettes *palettes) |
| 127 | { |
| 128 | int i; |
| 129 | |
| 130 | for (i = 0; i < palettes->count; i++) { |
| 131 | if (palettes->palette[i].id == id) |
| 132 | return &palettes->palette[i]; |
| 133 | } |
| 134 | return NULL; |
| 135 | } |
| 136 | |
| 137 | static av_cold int init_decoder(AVCodecContext *avctx) |
| 138 | { |
| 139 | avctx->pix_fmt = AV_PIX_FMT_PAL8; |
| 140 | |
| 141 | return 0; |
| 142 | } |
| 143 | |
| 144 | static av_cold int close_decoder(AVCodecContext *avctx) |
| 145 | { |
| 146 | flush_cache(avctx); |
| 147 | |
| 148 | return 0; |
| 149 | } |
| 150 | |
| 151 | /** |
| 152 | * Decode the RLE data. |
| 153 | * |
| 154 | * The subtitle is stored as a Run Length Encoded image. |
| 155 | * |
| 156 | * @param avctx contains the current codec context |
| 157 | * @param sub pointer to the processed subtitle data |
| 158 | * @param buf pointer to the RLE data to process |
| 159 | * @param buf_size size of the RLE data to process |
| 160 | */ |
| 161 | static int decode_rle(AVCodecContext *avctx, AVSubtitleRect *rect, |
| 162 | const uint8_t *buf, unsigned int buf_size) |
| 163 | { |
| 164 | const uint8_t *rle_bitmap_end; |
| 165 | int pixel_count, line_count; |
| 166 | |
| 167 | rle_bitmap_end = buf + buf_size; |
| 168 | |
| 169 | rect->pict.data[0] = av_malloc(rect->w * rect->h); |
| 170 | |
| 171 | if (!rect->pict.data[0]) |
| 172 | return AVERROR(ENOMEM); |
| 173 | |
| 174 | pixel_count = 0; |
| 175 | line_count = 0; |
| 176 | |
| 177 | while (buf < rle_bitmap_end && line_count < rect->h) { |
| 178 | uint8_t flags, color; |
| 179 | int run; |
| 180 | |
| 181 | color = bytestream_get_byte(&buf); |
| 182 | run = 1; |
| 183 | |
| 184 | if (color == 0x00) { |
| 185 | flags = bytestream_get_byte(&buf); |
| 186 | run = flags & 0x3f; |
| 187 | if (flags & 0x40) |
| 188 | run = (run << 8) + bytestream_get_byte(&buf); |
| 189 | color = flags & 0x80 ? bytestream_get_byte(&buf) : 0; |
| 190 | } |
| 191 | |
| 192 | if (run > 0 && pixel_count + run <= rect->w * rect->h) { |
| 193 | memset(rect->pict.data[0] + pixel_count, color, run); |
| 194 | pixel_count += run; |
| 195 | } else if (!run) { |
| 196 | /* |
| 197 | * New Line. Check if correct pixels decoded, if not display warning |
| 198 | * and adjust bitmap pointer to correct new line position. |
| 199 | */ |
| 200 | if (pixel_count % rect->w > 0) { |
| 201 | av_log(avctx, AV_LOG_ERROR, "Decoded %d pixels, when line should be %d pixels\n", |
| 202 | pixel_count % rect->w, rect->w); |
| 203 | if (avctx->err_recognition & AV_EF_EXPLODE) { |
| 204 | return AVERROR_INVALIDDATA; |
| 205 | } |
| 206 | } |
| 207 | line_count++; |
| 208 | } |
| 209 | } |
| 210 | |
| 211 | if (pixel_count < rect->w * rect->h) { |
| 212 | av_log(avctx, AV_LOG_ERROR, "Insufficient RLE data for subtitle\n"); |
| 213 | return AVERROR_INVALIDDATA; |
| 214 | } |
| 215 | |
| 216 | av_dlog(avctx, "Pixel Count = %d, Area = %d\n", pixel_count, rect->w * rect->h); |
| 217 | |
| 218 | return 0; |
| 219 | } |
| 220 | |
| 221 | /** |
| 222 | * Parse the picture segment packet. |
| 223 | * |
| 224 | * The picture segment contains details on the sequence id, |
| 225 | * width, height and Run Length Encoded (RLE) bitmap data. |
| 226 | * |
| 227 | * @param avctx contains the current codec context |
| 228 | * @param buf pointer to the packet to process |
| 229 | * @param buf_size size of packet to process |
| 230 | */ |
| 231 | static int parse_object_segment(AVCodecContext *avctx, |
| 232 | const uint8_t *buf, int buf_size) |
| 233 | { |
| 234 | PGSSubContext *ctx = avctx->priv_data; |
| 235 | PGSSubObject *object; |
| 236 | |
| 237 | uint8_t sequence_desc; |
| 238 | unsigned int rle_bitmap_len, width, height; |
| 239 | int id; |
| 240 | |
| 241 | if (buf_size <= 4) |
| 242 | return AVERROR_INVALIDDATA; |
| 243 | buf_size -= 4; |
| 244 | |
| 245 | id = bytestream_get_be16(&buf); |
| 246 | object = find_object(id, &ctx->objects); |
| 247 | if (!object) { |
| 248 | if (ctx->objects.count >= MAX_EPOCH_OBJECTS) { |
| 249 | av_log(avctx, AV_LOG_ERROR, "Too many objects in epoch\n"); |
| 250 | return AVERROR_INVALIDDATA; |
| 251 | } |
| 252 | object = &ctx->objects.object[ctx->objects.count++]; |
| 253 | object->id = id; |
| 254 | } |
| 255 | |
| 256 | /* skip object version number */ |
| 257 | buf += 1; |
| 258 | |
| 259 | /* Read the Sequence Description to determine if start of RLE data or appended to previous RLE */ |
| 260 | sequence_desc = bytestream_get_byte(&buf); |
| 261 | |
| 262 | if (!(sequence_desc & 0x80)) { |
| 263 | /* Additional RLE data */ |
| 264 | if (buf_size > object->rle_remaining_len) |
| 265 | return AVERROR_INVALIDDATA; |
| 266 | |
| 267 | memcpy(object->rle + object->rle_data_len, buf, buf_size); |
| 268 | object->rle_data_len += buf_size; |
| 269 | object->rle_remaining_len -= buf_size; |
| 270 | |
| 271 | return 0; |
| 272 | } |
| 273 | |
| 274 | if (buf_size <= 7) |
| 275 | return AVERROR_INVALIDDATA; |
| 276 | buf_size -= 7; |
| 277 | |
| 278 | /* Decode rle bitmap length, stored size includes width/height data */ |
| 279 | rle_bitmap_len = bytestream_get_be24(&buf) - 2*2; |
| 280 | |
| 281 | if (buf_size > rle_bitmap_len) { |
| 282 | av_log(avctx, AV_LOG_ERROR, |
| 283 | "Buffer dimension %d larger than the expected RLE data %d\n", |
| 284 | buf_size, rle_bitmap_len); |
| 285 | return AVERROR_INVALIDDATA; |
| 286 | } |
| 287 | |
| 288 | /* Get bitmap dimensions from data */ |
| 289 | width = bytestream_get_be16(&buf); |
| 290 | height = bytestream_get_be16(&buf); |
| 291 | |
| 292 | /* Make sure the bitmap is not too large */ |
| 293 | if (avctx->width < width || avctx->height < height) { |
| 294 | av_log(avctx, AV_LOG_ERROR, "Bitmap dimensions larger than video.\n"); |
| 295 | return AVERROR_INVALIDDATA; |
| 296 | } |
| 297 | |
| 298 | object->w = width; |
| 299 | object->h = height; |
| 300 | |
| 301 | av_fast_padded_malloc(&object->rle, &object->rle_buffer_size, rle_bitmap_len); |
| 302 | |
| 303 | if (!object->rle) |
| 304 | return AVERROR(ENOMEM); |
| 305 | |
| 306 | memcpy(object->rle, buf, buf_size); |
| 307 | object->rle_data_len = buf_size; |
| 308 | object->rle_remaining_len = rle_bitmap_len - buf_size; |
| 309 | |
| 310 | return 0; |
| 311 | } |
| 312 | |
| 313 | /** |
| 314 | * Parse the palette segment packet. |
| 315 | * |
| 316 | * The palette segment contains details of the palette, |
| 317 | * a maximum of 256 colors can be defined. |
| 318 | * |
| 319 | * @param avctx contains the current codec context |
| 320 | * @param buf pointer to the packet to process |
| 321 | * @param buf_size size of packet to process |
| 322 | */ |
| 323 | static int parse_palette_segment(AVCodecContext *avctx, |
| 324 | const uint8_t *buf, int buf_size) |
| 325 | { |
| 326 | PGSSubContext *ctx = avctx->priv_data; |
| 327 | PGSSubPalette *palette; |
| 328 | |
| 329 | const uint8_t *buf_end = buf + buf_size; |
| 330 | const uint8_t *cm = ff_crop_tab + MAX_NEG_CROP; |
| 331 | int color_id; |
| 332 | int y, cb, cr, alpha; |
| 333 | int r, g, b, r_add, g_add, b_add; |
| 334 | int id; |
| 335 | |
| 336 | id = bytestream_get_byte(&buf); |
| 337 | palette = find_palette(id, &ctx->palettes); |
| 338 | if (!palette) { |
| 339 | if (ctx->palettes.count >= MAX_EPOCH_PALETTES) { |
| 340 | av_log(avctx, AV_LOG_ERROR, "Too many palettes in epoch\n"); |
| 341 | return AVERROR_INVALIDDATA; |
| 342 | } |
| 343 | palette = &ctx->palettes.palette[ctx->palettes.count++]; |
| 344 | palette->id = id; |
| 345 | } |
| 346 | |
| 347 | /* Skip palette version */ |
| 348 | buf += 1; |
| 349 | |
| 350 | while (buf < buf_end) { |
| 351 | color_id = bytestream_get_byte(&buf); |
| 352 | y = bytestream_get_byte(&buf); |
| 353 | cr = bytestream_get_byte(&buf); |
| 354 | cb = bytestream_get_byte(&buf); |
| 355 | alpha = bytestream_get_byte(&buf); |
| 356 | |
| 357 | YUV_TO_RGB1(cb, cr); |
| 358 | YUV_TO_RGB2(r, g, b, y); |
| 359 | |
| 360 | av_dlog(avctx, "Color %d := (%d,%d,%d,%d)\n", color_id, r, g, b, alpha); |
| 361 | |
| 362 | /* Store color in palette */ |
| 363 | palette->clut[color_id] = RGBA(r,g,b,alpha); |
| 364 | } |
| 365 | return 0; |
| 366 | } |
| 367 | |
| 368 | /** |
| 369 | * Parse the presentation segment packet. |
| 370 | * |
| 371 | * The presentation segment contains details on the video |
| 372 | * width, video height, x & y subtitle position. |
| 373 | * |
| 374 | * @param avctx contains the current codec context |
| 375 | * @param buf pointer to the packet to process |
| 376 | * @param buf_size size of packet to process |
| 377 | * @todo TODO: Implement cropping |
| 378 | */ |
| 379 | static int parse_presentation_segment(AVCodecContext *avctx, |
| 380 | const uint8_t *buf, int buf_size, |
| 381 | int64_t pts) |
| 382 | { |
| 383 | PGSSubContext *ctx = avctx->priv_data; |
| 384 | int i, state, ret; |
| 385 | const uint8_t *buf_end = buf + buf_size; |
| 386 | |
| 387 | // Video descriptor |
| 388 | int w = bytestream_get_be16(&buf); |
| 389 | int h = bytestream_get_be16(&buf); |
| 390 | |
| 391 | ctx->presentation.pts = pts; |
| 392 | |
| 393 | av_dlog(avctx, "Video Dimensions %dx%d\n", |
| 394 | w, h); |
| 395 | ret = ff_set_dimensions(avctx, w, h); |
| 396 | if (ret < 0) |
| 397 | return ret; |
| 398 | |
| 399 | /* Skip 1 bytes of unknown, frame rate */ |
| 400 | buf++; |
| 401 | |
| 402 | // Composition descriptor |
| 403 | ctx->presentation.id_number = bytestream_get_be16(&buf); |
| 404 | /* |
| 405 | * state is a 2 bit field that defines pgs epoch boundaries |
| 406 | * 00 - Normal, previously defined objects and palettes are still valid |
| 407 | * 01 - Acquisition point, previous objects and palettes can be released |
| 408 | * 10 - Epoch start, previous objects and palettes can be released |
| 409 | * 11 - Epoch continue, previous objects and palettes can be released |
| 410 | * |
| 411 | * reserved 6 bits discarded |
| 412 | */ |
| 413 | state = bytestream_get_byte(&buf) >> 6; |
| 414 | if (state != 0) { |
| 415 | flush_cache(avctx); |
| 416 | } |
| 417 | |
| 418 | /* |
| 419 | * skip palette_update_flag (0x80), |
| 420 | */ |
| 421 | buf += 1; |
| 422 | ctx->presentation.palette_id = bytestream_get_byte(&buf); |
| 423 | ctx->presentation.object_count = bytestream_get_byte(&buf); |
| 424 | if (ctx->presentation.object_count > MAX_OBJECT_REFS) { |
| 425 | av_log(avctx, AV_LOG_ERROR, |
| 426 | "Invalid number of presentation objects %d\n", |
| 427 | ctx->presentation.object_count); |
| 428 | ctx->presentation.object_count = 2; |
| 429 | if (avctx->err_recognition & AV_EF_EXPLODE) { |
| 430 | return AVERROR_INVALIDDATA; |
| 431 | } |
| 432 | } |
| 433 | |
| 434 | |
| 435 | for (i = 0; i < ctx->presentation.object_count; i++) |
| 436 | { |
| 437 | |
| 438 | if (buf_end - buf < 8) { |
| 439 | av_log(avctx, AV_LOG_ERROR, "Insufficent space for object\n"); |
| 440 | ctx->presentation.object_count = i; |
| 441 | return AVERROR_INVALIDDATA; |
| 442 | } |
| 443 | |
| 444 | ctx->presentation.objects[i].id = bytestream_get_be16(&buf); |
| 445 | ctx->presentation.objects[i].window_id = bytestream_get_byte(&buf); |
| 446 | ctx->presentation.objects[i].composition_flag = bytestream_get_byte(&buf); |
| 447 | |
| 448 | ctx->presentation.objects[i].x = bytestream_get_be16(&buf); |
| 449 | ctx->presentation.objects[i].y = bytestream_get_be16(&buf); |
| 450 | |
| 451 | // If cropping |
| 452 | if (ctx->presentation.objects[i].composition_flag & 0x80) { |
| 453 | ctx->presentation.objects[i].crop_x = bytestream_get_be16(&buf); |
| 454 | ctx->presentation.objects[i].crop_y = bytestream_get_be16(&buf); |
| 455 | ctx->presentation.objects[i].crop_w = bytestream_get_be16(&buf); |
| 456 | ctx->presentation.objects[i].crop_h = bytestream_get_be16(&buf); |
| 457 | } |
| 458 | |
| 459 | av_dlog(avctx, "Subtitle Placement x=%d, y=%d\n", |
| 460 | ctx->presentation.objects[i].x, ctx->presentation.objects[i].y); |
| 461 | |
| 462 | if (ctx->presentation.objects[i].x > avctx->width || |
| 463 | ctx->presentation.objects[i].y > avctx->height) { |
| 464 | av_log(avctx, AV_LOG_ERROR, "Subtitle out of video bounds. x = %d, y = %d, video width = %d, video height = %d.\n", |
| 465 | ctx->presentation.objects[i].x, |
| 466 | ctx->presentation.objects[i].y, |
| 467 | avctx->width, avctx->height); |
| 468 | ctx->presentation.objects[i].x = 0; |
| 469 | ctx->presentation.objects[i].y = 0; |
| 470 | if (avctx->err_recognition & AV_EF_EXPLODE) { |
| 471 | return AVERROR_INVALIDDATA; |
| 472 | } |
| 473 | } |
| 474 | } |
| 475 | |
| 476 | return 0; |
| 477 | } |
| 478 | |
| 479 | /** |
| 480 | * Parse the display segment packet. |
| 481 | * |
| 482 | * The display segment controls the updating of the display. |
| 483 | * |
| 484 | * @param avctx contains the current codec context |
| 485 | * @param data pointer to the data pertaining the subtitle to display |
| 486 | * @param buf pointer to the packet to process |
| 487 | * @param buf_size size of packet to process |
| 488 | */ |
| 489 | static int display_end_segment(AVCodecContext *avctx, void *data, |
| 490 | const uint8_t *buf, int buf_size) |
| 491 | { |
| 492 | AVSubtitle *sub = data; |
| 493 | PGSSubContext *ctx = avctx->priv_data; |
| 494 | int64_t pts; |
| 495 | PGSSubPalette *palette; |
| 496 | int i, ret; |
| 497 | |
| 498 | pts = ctx->presentation.pts != AV_NOPTS_VALUE ? ctx->presentation.pts : sub->pts; |
| 499 | memset(sub, 0, sizeof(*sub)); |
| 500 | sub->pts = pts; |
| 501 | ctx->presentation.pts = AV_NOPTS_VALUE; |
| 502 | sub->start_display_time = 0; |
| 503 | // There is no explicit end time for PGS subtitles. The end time |
| 504 | // is defined by the start of the next sub which may contain no |
| 505 | // objects (i.e. clears the previous sub) |
| 506 | sub->end_display_time = UINT32_MAX; |
| 507 | sub->format = 0; |
| 508 | |
| 509 | // Blank if last object_count was 0. |
| 510 | if (!ctx->presentation.object_count) |
| 511 | return 1; |
| 512 | sub->rects = av_mallocz(sizeof(*sub->rects) * ctx->presentation.object_count); |
| 513 | if (!sub->rects) { |
| 514 | return AVERROR(ENOMEM); |
| 515 | } |
| 516 | palette = find_palette(ctx->presentation.palette_id, &ctx->palettes); |
| 517 | if (!palette) { |
| 518 | // Missing palette. Should only happen with damaged streams. |
| 519 | av_log(avctx, AV_LOG_ERROR, "Invalid palette id %d\n", |
| 520 | ctx->presentation.palette_id); |
| 521 | avsubtitle_free(sub); |
| 522 | return AVERROR_INVALIDDATA; |
| 523 | } |
| 524 | for (i = 0; i < ctx->presentation.object_count; i++) { |
| 525 | PGSSubObject *object; |
| 526 | |
| 527 | sub->rects[i] = av_mallocz(sizeof(*sub->rects[0])); |
| 528 | if (!sub->rects[i]) { |
| 529 | avsubtitle_free(sub); |
| 530 | return AVERROR(ENOMEM); |
| 531 | } |
| 532 | sub->num_rects++; |
| 533 | sub->rects[i]->type = SUBTITLE_BITMAP; |
| 534 | |
| 535 | /* Process bitmap */ |
| 536 | object = find_object(ctx->presentation.objects[i].id, &ctx->objects); |
| 537 | if (!object) { |
| 538 | // Missing object. Should only happen with damaged streams. |
| 539 | av_log(avctx, AV_LOG_ERROR, "Invalid object id %d\n", |
| 540 | ctx->presentation.objects[i].id); |
| 541 | if (avctx->err_recognition & AV_EF_EXPLODE) { |
| 542 | avsubtitle_free(sub); |
| 543 | return AVERROR_INVALIDDATA; |
| 544 | } |
| 545 | // Leaves rect empty with 0 width and height. |
| 546 | continue; |
| 547 | } |
| 548 | if (ctx->presentation.objects[i].composition_flag & 0x40) |
| 549 | sub->rects[i]->flags |= AV_SUBTITLE_FLAG_FORCED; |
| 550 | |
| 551 | sub->rects[i]->x = ctx->presentation.objects[i].x; |
| 552 | sub->rects[i]->y = ctx->presentation.objects[i].y; |
| 553 | sub->rects[i]->w = object->w; |
| 554 | sub->rects[i]->h = object->h; |
| 555 | |
| 556 | sub->rects[i]->pict.linesize[0] = object->w; |
| 557 | |
| 558 | if (object->rle) { |
| 559 | if (object->rle_remaining_len) { |
| 560 | av_log(avctx, AV_LOG_ERROR, "RLE data length %u is %u bytes shorter than expected\n", |
| 561 | object->rle_data_len, object->rle_remaining_len); |
| 562 | if (avctx->err_recognition & AV_EF_EXPLODE) { |
| 563 | avsubtitle_free(sub); |
| 564 | return AVERROR_INVALIDDATA; |
| 565 | } |
| 566 | } |
| 567 | ret = decode_rle(avctx, sub->rects[i], object->rle, object->rle_data_len); |
| 568 | if (ret < 0) { |
| 569 | if ((avctx->err_recognition & AV_EF_EXPLODE) || |
| 570 | ret == AVERROR(ENOMEM)) { |
| 571 | avsubtitle_free(sub); |
| 572 | return ret; |
| 573 | } |
| 574 | sub->rects[i]->w = 0; |
| 575 | sub->rects[i]->h = 0; |
| 576 | continue; |
| 577 | } |
| 578 | } |
| 579 | /* Allocate memory for colors */ |
| 580 | sub->rects[i]->nb_colors = 256; |
| 581 | sub->rects[i]->pict.data[1] = av_mallocz(AVPALETTE_SIZE); |
| 582 | if (!sub->rects[i]->pict.data[1]) { |
| 583 | avsubtitle_free(sub); |
| 584 | return AVERROR(ENOMEM); |
| 585 | } |
| 586 | |
| 587 | if (!ctx->forced_subs_only || ctx->presentation.objects[i].composition_flag & 0x40) |
| 588 | memcpy(sub->rects[i]->pict.data[1], palette->clut, sub->rects[i]->nb_colors * sizeof(uint32_t)); |
| 589 | |
| 590 | } |
| 591 | return 1; |
| 592 | } |
| 593 | |
| 594 | static int decode(AVCodecContext *avctx, void *data, int *data_size, |
| 595 | AVPacket *avpkt) |
| 596 | { |
| 597 | const uint8_t *buf = avpkt->data; |
| 598 | int buf_size = avpkt->size; |
| 599 | |
| 600 | const uint8_t *buf_end; |
| 601 | uint8_t segment_type; |
| 602 | int segment_length; |
| 603 | int i, ret; |
| 604 | |
| 605 | av_dlog(avctx, "PGS sub packet:\n"); |
| 606 | |
| 607 | for (i = 0; i < buf_size; i++) { |
| 608 | av_dlog(avctx, "%02x ", buf[i]); |
| 609 | if (i % 16 == 15) |
| 610 | av_dlog(avctx, "\n"); |
| 611 | } |
| 612 | |
| 613 | if (i & 15) |
| 614 | av_dlog(avctx, "\n"); |
| 615 | |
| 616 | *data_size = 0; |
| 617 | |
| 618 | /* Ensure that we have received at a least a segment code and segment length */ |
| 619 | if (buf_size < 3) |
| 620 | return -1; |
| 621 | |
| 622 | buf_end = buf + buf_size; |
| 623 | |
| 624 | /* Step through buffer to identify segments */ |
| 625 | while (buf < buf_end) { |
| 626 | segment_type = bytestream_get_byte(&buf); |
| 627 | segment_length = bytestream_get_be16(&buf); |
| 628 | |
| 629 | av_dlog(avctx, "Segment Length %d, Segment Type %x\n", segment_length, segment_type); |
| 630 | |
| 631 | if (segment_type != DISPLAY_SEGMENT && segment_length > buf_end - buf) |
| 632 | break; |
| 633 | |
| 634 | ret = 0; |
| 635 | switch (segment_type) { |
| 636 | case PALETTE_SEGMENT: |
| 637 | ret = parse_palette_segment(avctx, buf, segment_length); |
| 638 | break; |
| 639 | case OBJECT_SEGMENT: |
| 640 | ret = parse_object_segment(avctx, buf, segment_length); |
| 641 | break; |
| 642 | case PRESENTATION_SEGMENT: |
| 643 | ret = parse_presentation_segment(avctx, buf, segment_length, ((AVSubtitle*)(data))->pts); |
| 644 | break; |
| 645 | case WINDOW_SEGMENT: |
| 646 | /* |
| 647 | * Window Segment Structure (No new information provided): |
| 648 | * 2 bytes: Unknown, |
| 649 | * 2 bytes: X position of subtitle, |
| 650 | * 2 bytes: Y position of subtitle, |
| 651 | * 2 bytes: Width of subtitle, |
| 652 | * 2 bytes: Height of subtitle. |
| 653 | */ |
| 654 | break; |
| 655 | case DISPLAY_SEGMENT: |
| 656 | ret = display_end_segment(avctx, data, buf, segment_length); |
| 657 | if (ret >= 0) |
| 658 | *data_size = ret; |
| 659 | break; |
| 660 | default: |
| 661 | av_log(avctx, AV_LOG_ERROR, "Unknown subtitle segment type 0x%x, length %d\n", |
| 662 | segment_type, segment_length); |
| 663 | ret = AVERROR_INVALIDDATA; |
| 664 | break; |
| 665 | } |
| 666 | if (ret < 0 && (avctx->err_recognition & AV_EF_EXPLODE)) |
| 667 | return ret; |
| 668 | |
| 669 | buf += segment_length; |
| 670 | } |
| 671 | |
| 672 | return buf_size; |
| 673 | } |
| 674 | |
| 675 | #define OFFSET(x) offsetof(PGSSubContext, x) |
| 676 | #define SD AV_OPT_FLAG_SUBTITLE_PARAM | AV_OPT_FLAG_DECODING_PARAM |
| 677 | static const AVOption options[] = { |
| 678 | {"forced_subs_only", "Only show forced subtitles", OFFSET(forced_subs_only), AV_OPT_TYPE_INT, {.i64 = 0}, 0, 1, SD}, |
| 679 | { NULL }, |
| 680 | }; |
| 681 | |
| 682 | static const AVClass pgsdec_class = { |
| 683 | .class_name = "PGS subtitle decoder", |
| 684 | .item_name = av_default_item_name, |
| 685 | .option = options, |
| 686 | .version = LIBAVUTIL_VERSION_INT, |
| 687 | }; |
| 688 | |
| 689 | AVCodec ff_pgssub_decoder = { |
| 690 | .name = "pgssub", |
| 691 | .long_name = NULL_IF_CONFIG_SMALL("HDMV Presentation Graphic Stream subtitles"), |
| 692 | .type = AVMEDIA_TYPE_SUBTITLE, |
| 693 | .id = AV_CODEC_ID_HDMV_PGS_SUBTITLE, |
| 694 | .priv_data_size = sizeof(PGSSubContext), |
| 695 | .init = init_decoder, |
| 696 | .close = close_decoder, |
| 697 | .decode = decode, |
| 698 | .priv_class = &pgsdec_class, |
| 699 | }; |