2 * DVD subtitle decoding
3 * Copyright (c) 2005 Fabrice Bellard
5 * This file is part of FFmpeg.
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.
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.
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
26 #include "libavutil/attributes.h"
27 #include "libavutil/colorspace.h"
28 #include "libavutil/opt.h"
29 #include "libavutil/imgutils.h"
30 #include "libavutil/avstring.h"
31 #include "libavutil/bswap.h"
33 typedef struct DVDSubContext
45 uint8_t used_color[256];
51 static void yuv_a_to_rgba(const uint8_t *ycbcr, const uint8_t *alpha, uint32_t *rgba, int num_values)
53 const uint8_t *cm = ff_crop_tab + MAX_NEG_CROP;
56 int r_add, g_add, b_add;
58 for (i = num_values; i > 0; i--) {
62 YUV_TO_RGB1_CCIR(cb, cr);
63 YUV_TO_RGB2_CCIR(r, g, b, y);
64 *rgba++ = ((unsigned)*alpha++ << 24) | (r << 16) | (g << 8) | b;
68 static int decode_run_2bit(GetBitContext *gb, int *color)
73 for (t = 1; v < t && t <= 0x40; t <<= 2)
74 v = (v << 4) | get_bits(gb, 4);
76 if (v < 4) { /* Code for fill rest of line */
82 static int decode_run_8bit(GetBitContext *gb, int *color)
85 int has_run = get_bits1(gb);
87 *color = get_bits(gb, 8);
89 *color = get_bits(gb, 2);
92 len = get_bits(gb, 7);
98 len = get_bits(gb, 3) + 2;
104 static int decode_rle(uint8_t *bitmap, int linesize, int w, int h, uint8_t used_color[256],
105 const uint8_t *buf, int start, int buf_size, int is_8bit)
109 int x, y, len, color;
112 if (start >= buf_size)
115 if (w <= 0 || h <= 0)
118 bit_len = (buf_size - start) * 8;
119 init_get_bits(&gb, buf + start, bit_len);
125 if (get_bits_count(&gb) > bit_len)
128 len = decode_run_8bit(&gb, &color);
130 len = decode_run_2bit(&gb, &color);
131 len = FFMIN(len, w - x);
132 memset(d + x, color, len);
133 used_color[color] = 1;
148 static void guess_palette(DVDSubContext* ctx,
149 uint32_t *rgba_palette,
150 uint32_t subtitle_color)
152 static const uint8_t level_map[4][4] = {
153 // this configuration (full range, lowest to highest) in tests
154 // seemed most common, so assume this
158 {0x00, 0x55, 0xaa, 0xff},
160 uint8_t color_used[16] = { 0 };
161 int nb_opaque_colors, i, level, j, r, g, b;
162 uint8_t *colormap = ctx->colormap, *alpha = ctx->alpha;
164 if(ctx->has_palette) {
165 for(i = 0; i < 4; i++)
166 rgba_palette[i] = (ctx->palette[colormap[i]] & 0x00ffffff)
167 | ((alpha[i] * 17U) << 24);
171 for(i = 0; i < 4; i++)
174 nb_opaque_colors = 0;
175 for(i = 0; i < 4; i++) {
176 if (alpha[i] != 0 && !color_used[colormap[i]]) {
177 color_used[colormap[i]] = 1;
182 if (nb_opaque_colors == 0)
186 memset(color_used, 0, 16);
187 for(i = 0; i < 4; i++) {
189 if (!color_used[colormap[i]]) {
190 level = level_map[nb_opaque_colors - 1][j];
191 r = (((subtitle_color >> 16) & 0xff) * level) >> 8;
192 g = (((subtitle_color >> 8) & 0xff) * level) >> 8;
193 b = (((subtitle_color >> 0) & 0xff) * level) >> 8;
194 rgba_palette[i] = b | (g << 8) | (r << 16) | ((alpha[i] * 17U) << 24);
195 color_used[colormap[i]] = (i + 1);
198 rgba_palette[i] = (rgba_palette[color_used[colormap[i]] - 1] & 0x00ffffff) |
199 ((alpha[i] * 17U) << 24);
205 static void reset_rects(AVSubtitle *sub_header)
209 if (sub_header->rects) {
210 for (i = 0; i < sub_header->num_rects; i++) {
211 av_freep(&sub_header->rects[i]->data[0]);
212 av_freep(&sub_header->rects[i]->data[1]);
213 av_freep(&sub_header->rects[i]);
215 av_freep(&sub_header->rects);
216 sub_header->num_rects = 0;
220 #define READ_OFFSET(a) (big_offsets ? AV_RB32(a) : AV_RB16(a))
222 static int decode_dvd_subtitles(DVDSubContext *ctx, AVSubtitle *sub_header,
223 const uint8_t *buf, int buf_size)
225 int cmd_pos, pos, cmd, x1, y1, x2, y2, next_cmd_pos;
226 int big_offsets, offset_size, is_8bit = 0;
227 const uint8_t *yuv_palette = NULL;
228 uint8_t *colormap = ctx->colormap, *alpha = ctx->alpha;
233 int64_t offset1, offset2;
238 if (AV_RB16(buf) == 0) { /* HD subpicture with 4-byte offsets */
248 size = READ_OFFSET(buf + (big_offsets ? 2 : 0));
249 cmd_pos = READ_OFFSET(buf + cmd_pos);
251 if (cmd_pos < 0 || cmd_pos > buf_size - 2 - offset_size) {
252 if (cmd_pos > size) {
253 av_log(ctx, AV_LOG_ERROR, "Discarding invalid packet\n");
256 return AVERROR(EAGAIN);
259 while (cmd_pos > 0 && cmd_pos < buf_size - 2 - offset_size) {
260 date = AV_RB16(buf + cmd_pos);
261 next_cmd_pos = READ_OFFSET(buf + cmd_pos + 2);
262 ff_dlog(NULL, "cmd_pos=0x%04x next=0x%04x date=%d\n",
263 cmd_pos, next_cmd_pos, date);
264 pos = cmd_pos + 2 + offset_size;
267 x1 = y1 = x2 = y2 = 0;
268 while (pos < buf_size) {
270 ff_dlog(NULL, "cmd=%02x\n", cmd);
273 /* menu subpicture */
278 sub_header->start_display_time = (date << 10) / 90;
282 sub_header->end_display_time = (date << 10) / 90;
286 if ((buf_size - pos) < 2)
288 colormap[3] = buf[pos] >> 4;
289 colormap[2] = buf[pos] & 0x0f;
290 colormap[1] = buf[pos + 1] >> 4;
291 colormap[0] = buf[pos + 1] & 0x0f;
296 if ((buf_size - pos) < 2)
298 alpha[3] = buf[pos] >> 4;
299 alpha[2] = buf[pos] & 0x0f;
300 alpha[1] = buf[pos + 1] >> 4;
301 alpha[0] = buf[pos + 1] & 0x0f;
303 ff_dlog(NULL, "alpha=%x%x%x%x\n", alpha[0],alpha[1],alpha[2],alpha[3]);
307 if ((buf_size - pos) < 6)
309 x1 = (buf[pos] << 4) | (buf[pos + 1] >> 4);
310 x2 = ((buf[pos + 1] & 0x0f) << 8) | buf[pos + 2];
311 y1 = (buf[pos + 3] << 4) | (buf[pos + 4] >> 4);
312 y2 = ((buf[pos + 4] & 0x0f) << 8) | buf[pos + 5];
315 ff_dlog(NULL, "x1=%d x2=%d y1=%d y2=%d\n", x1, x2, y1, y2);
319 if ((buf_size - pos) < 4)
321 offset1 = AV_RB16(buf + pos);
322 offset2 = AV_RB16(buf + pos + 2);
323 ff_dlog(NULL, "offset1=0x%04"PRIx64" offset2=0x%04"PRIx64"\n", offset1, offset2);
327 if ((buf_size - pos) < 8)
329 offset1 = AV_RB32(buf + pos);
330 offset2 = AV_RB32(buf + pos + 4);
331 ff_dlog(NULL, "offset1=0x%04"PRIx64" offset2=0x%04"PRIx64"\n", offset1, offset2);
337 if ((buf_size - pos) < 768)
339 yuv_palette = buf + pos;
343 /* HD set contrast (alpha) */
344 if ((buf_size - pos) < 256)
346 for (i = 0; i < 256; i++)
347 alpha[i] = 0xFF - buf[pos+i];
354 ff_dlog(NULL, "unrecognised subpicture command 0x%x\n", cmd);
359 if (offset1 >= buf_size || offset2 >= buf_size)
362 if (offset1 >= 0 && offset2 >= 0) {
366 /* decode the bitmap */
373 if (w > 0 && h > 1) {
374 reset_rects(sub_header);
375 memset(ctx->used_color, 0, sizeof(ctx->used_color));
376 sub_header->rects = av_mallocz(sizeof(*sub_header->rects));
377 if (!sub_header->rects)
379 sub_header->rects[0] = av_mallocz(sizeof(AVSubtitleRect));
380 if (!sub_header->rects[0])
382 sub_header->num_rects = 1;
383 bitmap = sub_header->rects[0]->data[0] = av_malloc(w * h);
386 if (decode_rle(bitmap, w * 2, w, (h + 1) / 2, ctx->used_color,
387 buf, offset1, buf_size, is_8bit) < 0)
389 if (decode_rle(bitmap + w, w * 2, w, h / 2, ctx->used_color,
390 buf, offset2, buf_size, is_8bit) < 0)
392 sub_header->rects[0]->data[1] = av_mallocz(AVPALETTE_SIZE);
393 if (!sub_header->rects[0]->data[1])
398 sub_header->rects[0]->nb_colors = 256;
399 yuv_a_to_rgba(yuv_palette, alpha,
400 (uint32_t *)sub_header->rects[0]->data[1],
403 sub_header->rects[0]->nb_colors = 4;
404 guess_palette(ctx, (uint32_t*)sub_header->rects[0]->data[1],
407 sub_header->rects[0]->x = x1;
408 sub_header->rects[0]->y = y1;
409 sub_header->rects[0]->w = w;
410 sub_header->rects[0]->h = h;
411 sub_header->rects[0]->type = SUBTITLE_BITMAP;
412 sub_header->rects[0]->linesize[0] = w;
413 sub_header->rects[0]->flags = is_menu ? AV_SUBTITLE_FLAG_FORCED : 0;
416 FF_DISABLE_DEPRECATION_WARNINGS
417 for (i = 0; i < 4; i++) {
418 sub_header->rects[0]->pict.data[i] = sub_header->rects[0]->data[i];
419 sub_header->rects[0]->pict.linesize[i] = sub_header->rects[0]->linesize[i];
421 FF_ENABLE_DEPRECATION_WARNINGS
425 if (next_cmd_pos < cmd_pos) {
426 av_log(ctx, AV_LOG_ERROR, "Invalid command offset\n");
429 if (next_cmd_pos == cmd_pos)
431 cmd_pos = next_cmd_pos;
433 if (sub_header->num_rects > 0)
436 reset_rects(sub_header);
440 static int is_transp(const uint8_t *buf, int pitch, int n,
441 const uint8_t *transp_color)
444 for(i = 0; i < n; i++) {
445 if (!transp_color[*buf])
452 /* return 0 if empty rectangle, 1 if non empty */
453 static int find_smallest_bounding_rectangle(DVDSubContext *ctx, AVSubtitle *s)
455 uint8_t transp_color[256] = { 0 };
456 int y1, y2, x1, x2, y, w, h, i;
460 if (s->num_rects == 0 || !s->rects || s->rects[0]->w <= 0 || s->rects[0]->h <= 0)
463 for(i = 0; i < s->rects[0]->nb_colors; i++) {
464 if ((((uint32_t *)s->rects[0]->data[1])[i] >> 24) == 0) {
466 } else if (ctx->used_color[i])
472 while (y1 < s->rects[0]->h && is_transp(s->rects[0]->data[0] + y1 * s->rects[0]->linesize[0],
473 1, s->rects[0]->w, transp_color))
475 if (y1 == s->rects[0]->h) {
476 av_freep(&s->rects[0]->data[0]);
477 s->rects[0]->w = s->rects[0]->h = 0;
481 y2 = s->rects[0]->h - 1;
482 while (y2 > 0 && is_transp(s->rects[0]->data[0] + y2 * s->rects[0]->linesize[0], 1,
483 s->rects[0]->w, transp_color))
486 while (x1 < (s->rects[0]->w - 1) && is_transp(s->rects[0]->data[0] + x1, s->rects[0]->linesize[0],
487 s->rects[0]->h, transp_color))
489 x2 = s->rects[0]->w - 1;
490 while (x2 > 0 && is_transp(s->rects[0]->data[0] + x2, s->rects[0]->linesize[0], s->rects[0]->h,
495 bitmap = av_malloc(w * h);
498 for(y = 0; y < h; y++) {
499 memcpy(bitmap + w * y, s->rects[0]->data[0] + x1 + (y1 + y) * s->rects[0]->linesize[0], w);
501 av_freep(&s->rects[0]->data[0]);
502 s->rects[0]->data[0] = bitmap;
503 s->rects[0]->linesize[0] = w;
506 s->rects[0]->x += x1;
507 s->rects[0]->y += y1;
510 FF_DISABLE_DEPRECATION_WARNINGS
511 for (i = 0; i < 4; i++) {
512 s->rects[0]->pict.data[i] = s->rects[0]->data[i];
513 s->rects[0]->pict.linesize[i] = s->rects[0]->linesize[i];
515 FF_ENABLE_DEPRECATION_WARNINGS
522 #define ALPHA_MIX(A,BACK,FORE) (((255-(A)) * (BACK) + (A) * (FORE)) / 255)
523 static void ppm_save(const char *filename, uint8_t *bitmap, int w, int h,
524 uint32_t *rgba_palette)
528 int back[3] = {0, 255, 0}; /* green background */
531 f = fopen(filename, "w");
540 for(y = 0; y < h; y++) {
541 for(x = 0; x < w; x++) {
542 v = rgba_palette[bitmap[y * w + x]];
544 putc(ALPHA_MIX(alpha, back[0], (v >> 16) & 0xff), f);
545 putc(ALPHA_MIX(alpha, back[1], (v >> 8) & 0xff), f);
546 putc(ALPHA_MIX(alpha, back[2], (v >> 0) & 0xff), f);
553 static int append_to_cached_buf(AVCodecContext *avctx,
554 const uint8_t *buf, int buf_size)
556 DVDSubContext *ctx = avctx->priv_data;
558 av_assert0(buf_size >= 0 && ctx->buf_size <= sizeof(ctx->buf));
559 if (buf_size >= sizeof(ctx->buf) - ctx->buf_size) {
560 av_log(avctx, AV_LOG_WARNING, "Attempt to reconstruct "
561 "too large SPU packets aborted.\n");
563 return AVERROR_INVALIDDATA;
565 memcpy(ctx->buf + ctx->buf_size, buf, buf_size);
566 ctx->buf_size += buf_size;
570 static int dvdsub_decode(AVCodecContext *avctx,
571 void *data, int *data_size,
574 DVDSubContext *ctx = avctx->priv_data;
575 const uint8_t *buf = avpkt->data;
576 int buf_size = avpkt->size;
577 AVSubtitle *sub = data;
582 int ret = append_to_cached_buf(avctx, buf, buf_size);
588 buf_size = ctx->buf_size;
592 is_menu = decode_dvd_subtitles(ctx, sub, buf, buf_size);
593 if (is_menu == AVERROR(EAGAIN)) {
595 return appended ? 0 : append_to_cached_buf(avctx, buf, buf_size);
605 if (!is_menu && find_smallest_bounding_rectangle(ctx, sub) == 0)
608 if (ctx->forced_subs_only && !(sub->rects[0]->flags & AV_SUBTITLE_FLAG_FORCED))
615 snprintf(ppm_name, sizeof(ppm_name), "/tmp/%05d.ppm", ctx->sub_id++);
616 ff_dlog(NULL, "start=%d ms end =%d ms\n",
617 sub->start_display_time,
618 sub->end_display_time);
619 ppm_save(ppm_name, sub->rects[0]->data[0],
620 sub->rects[0]->w, sub->rects[0]->h, (uint32_t*) sub->rects[0]->data[1]);
629 static void parse_palette(DVDSubContext *ctx, char *p)
633 ctx->has_palette = 1;
635 ctx->palette[i] = strtoul(p, &p, 16);
636 while(*p == ',' || av_isspace(*p))
641 static int parse_ifo_palette(DVDSubContext *ctx, char *p)
645 uint32_t sp_pgci, pgci, off_pgc, pgc;
646 uint8_t r, g, b, yuv[65], *buf;
647 int i, y, cb, cr, r_add, g_add, b_add;
649 const uint8_t *cm = ff_crop_tab + MAX_NEG_CROP;
651 ctx->has_palette = 0;
652 if ((ifo = fopen(p, "r")) == NULL) {
653 av_log(ctx, AV_LOG_WARNING, "Unable to open IFO file \"%s\": %s\n", p, av_err2str(AVERROR(errno)));
656 if (fread(ifostr, 12, 1, ifo) != 1 || memcmp(ifostr, "DVDVIDEO-VTS", 12)) {
657 av_log(ctx, AV_LOG_WARNING, "\"%s\" is not a proper IFO file\n", p);
658 ret = AVERROR_INVALIDDATA;
661 if (fseek(ifo, 0xCC, SEEK_SET) == -1) {
662 ret = AVERROR(errno);
665 if (fread(&sp_pgci, 4, 1, ifo) == 1) {
666 pgci = av_be2ne32(sp_pgci) * 2048;
667 if (fseek(ifo, pgci + 0x0C, SEEK_SET) == -1) {
668 ret = AVERROR(errno);
671 if (fread(&off_pgc, 4, 1, ifo) == 1) {
672 pgc = pgci + av_be2ne32(off_pgc);
673 if (fseek(ifo, pgc + 0xA4, SEEK_SET) == -1) {
674 ret = AVERROR(errno);
677 if (fread(yuv, 64, 1, ifo) == 1) {
679 for(i=0; i<16; i++) {
683 YUV_TO_RGB1_CCIR(cb, cr);
684 YUV_TO_RGB2_CCIR(r, g, b, y);
685 ctx->palette[i] = (r << 16) + (g << 8) + b;
688 ctx->has_palette = 1;
692 if (ctx->has_palette == 0) {
693 av_log(ctx, AV_LOG_WARNING, "Failed to read palette from IFO file \"%s\"\n", p);
694 ret = AVERROR_INVALIDDATA;
701 static int dvdsub_parse_extradata(AVCodecContext *avctx)
703 DVDSubContext *ctx = (DVDSubContext*) avctx->priv_data;
704 char *dataorig, *data;
707 if (!avctx->extradata || !avctx->extradata_size)
710 dataorig = data = av_malloc(avctx->extradata_size+1);
712 return AVERROR(ENOMEM);
713 memcpy(data, avctx->extradata, avctx->extradata_size);
714 data[avctx->extradata_size] = '\0';
717 int pos = strcspn(data, "\n\r");
718 if (pos==0 && *data==0)
721 if (strncmp("palette:", data, 8) == 0) {
722 parse_palette(ctx, data + 8);
723 } else if (strncmp("size:", data, 5) == 0) {
725 if (sscanf(data + 5, "%dx%d", &w, &h) == 2) {
726 ret = ff_set_dimensions(avctx, w, h);
733 data += strspn(data, "\n\r");
741 static av_cold int dvdsub_init(AVCodecContext *avctx)
743 DVDSubContext *ctx = avctx->priv_data;
746 if ((ret = dvdsub_parse_extradata(avctx)) < 0)
750 parse_ifo_palette(ctx, ctx->ifo_str);
751 if (ctx->palette_str)
752 parse_palette(ctx, ctx->palette_str);
753 if (ctx->has_palette) {
755 av_log(avctx, AV_LOG_DEBUG, "palette:");
757 av_log(avctx, AV_LOG_DEBUG, " 0x%06"PRIx32, ctx->palette[i]);
758 av_log(avctx, AV_LOG_DEBUG, "\n");
764 static void dvdsub_flush(AVCodecContext *avctx)
766 DVDSubContext *ctx = avctx->priv_data;
770 static av_cold int dvdsub_close(AVCodecContext *avctx)
776 #define OFFSET(field) offsetof(DVDSubContext, field)
777 #define SD AV_OPT_FLAG_SUBTITLE_PARAM | AV_OPT_FLAG_DECODING_PARAM
778 static const AVOption options[] = {
779 { "palette", "set the global palette", OFFSET(palette_str), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, SD },
780 { "ifo_palette", "obtain the global palette from .IFO file", OFFSET(ifo_str), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, SD },
781 { "forced_subs_only", "Only show forced subtitles", OFFSET(forced_subs_only), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, SD},
784 static const AVClass dvdsub_class = {
785 .class_name = "dvdsubdec",
786 .item_name = av_default_item_name,
788 .version = LIBAVUTIL_VERSION_INT,
791 AVCodec ff_dvdsub_decoder = {
793 .long_name = NULL_IF_CONFIG_SMALL("DVD subtitles"),
794 .type = AVMEDIA_TYPE_SUBTITLE,
795 .id = AV_CODEC_ID_DVD_SUBTITLE,
796 .priv_data_size = sizeof(DVDSubContext),
798 .decode = dvdsub_decode,
799 .flush = dvdsub_flush,
800 .close = dvdsub_close,
801 .priv_class = &dvdsub_class,