| /* |
| * Copyright (c) 2012 Clément Bœsch |
| * |
| * This file is part of FFmpeg. |
| * |
| * FFmpeg is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Lesser General Public |
| * License as published by the Free Software Foundation; either |
| * version 2.1 of the License, or (at your option) any later version. |
| * |
| * FFmpeg is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * Lesser General Public License for more details. |
| * |
| * You should have received a copy of the GNU Lesser General Public |
| * License along with FFmpeg; if not, write to the Free Software |
| * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| */ |
| |
| /** |
| * @file |
| * MicroDVD subtitle decoder |
| * |
| * Based on the specifications found here: |
| * https://trac.videolan.org/vlc/ticket/1825#comment:6 |
| */ |
| |
| #include "libavutil/avstring.h" |
| #include "libavutil/parseutils.h" |
| #include "libavutil/bprint.h" |
| #include "avcodec.h" |
| #include "ass.h" |
| |
| static int indexof(const char *s, int c) |
| { |
| char *f = strchr(s, c); |
| return f ? (f - s) : -1; |
| } |
| |
| struct microdvd_tag { |
| char key; |
| int persistent; |
| uint32_t data1; |
| uint32_t data2; |
| char *data_string; |
| int data_string_len; |
| }; |
| |
| #define MICRODVD_PERSISTENT_OFF 0 |
| #define MICRODVD_PERSISTENT_ON 1 |
| #define MICRODVD_PERSISTENT_OPENED 2 |
| |
| // Color, Font, Size, cHarset, stYle, Position, cOordinate |
| #define MICRODVD_TAGS "cfshyYpo" |
| |
| static void microdvd_set_tag(struct microdvd_tag *tags, struct microdvd_tag tag) |
| { |
| int tag_index = indexof(MICRODVD_TAGS, tag.key); |
| |
| if (tag_index < 0) |
| return; |
| memcpy(&tags[tag_index], &tag, sizeof(tag)); |
| } |
| |
| // italic, bold, underline, strike-through |
| #define MICRODVD_STYLES "ibus" |
| |
| /* some samples have lines that start with a / indicating non persistent italic |
| * marker */ |
| static char *check_for_italic_slash_marker(struct microdvd_tag *tags, char *s) |
| { |
| if (*s == '/') { |
| struct microdvd_tag tag = tags[indexof(MICRODVD_TAGS, 'y')]; |
| tag.key = 'y'; |
| tag.data1 |= 1 << 0 /* 'i' position in MICRODVD_STYLES */; |
| microdvd_set_tag(tags, tag); |
| s++; |
| } |
| return s; |
| } |
| |
| static char *microdvd_load_tags(struct microdvd_tag *tags, char *s) |
| { |
| s = check_for_italic_slash_marker(tags, s); |
| |
| while (*s == '{') { |
| char *start = s; |
| char tag_char = *(s + 1); |
| struct microdvd_tag tag = {0}; |
| |
| if (!tag_char || *(s + 2) != ':') |
| break; |
| s += 3; |
| |
| switch (tag_char) { |
| |
| /* Style */ |
| case 'Y': |
| tag.persistent = MICRODVD_PERSISTENT_ON; |
| case 'y': |
| while (*s && *s != '}') { |
| int style_index = indexof(MICRODVD_STYLES, *s); |
| |
| if (style_index >= 0) |
| tag.data1 |= (1 << style_index); |
| s++; |
| } |
| if (*s != '}') |
| break; |
| /* We must distinguish persistent and non-persistent styles |
| * to handle this kind of style tags: {y:ib}{Y:us} */ |
| tag.key = tag_char; |
| break; |
| |
| /* Color */ |
| case 'C': |
| tag.persistent = MICRODVD_PERSISTENT_ON; |
| case 'c': |
| while (*s == '$' || *s == '#') |
| s++; |
| tag.data1 = strtol(s, &s, 16) & 0x00ffffff; |
| if (*s != '}') |
| break; |
| tag.key = 'c'; |
| break; |
| |
| /* Font name */ |
| case 'F': |
| tag.persistent = MICRODVD_PERSISTENT_ON; |
| case 'f': { |
| int len = indexof(s, '}'); |
| if (len < 0) |
| break; |
| tag.data_string = s; |
| tag.data_string_len = len; |
| s += len; |
| tag.key = 'f'; |
| break; |
| } |
| |
| /* Font size */ |
| case 'S': |
| tag.persistent = MICRODVD_PERSISTENT_ON; |
| case 's': |
| tag.data1 = strtol(s, &s, 10); |
| if (*s != '}') |
| break; |
| tag.key = 's'; |
| break; |
| |
| /* Charset */ |
| case 'H': { |
| //TODO: not yet handled, just parsed. |
| int len = indexof(s, '}'); |
| if (len < 0) |
| break; |
| tag.data_string = s; |
| tag.data_string_len = len; |
| s += len; |
| tag.key = 'h'; |
| break; |
| } |
| |
| /* Position */ |
| case 'P': |
| if (!*s) |
| break; |
| tag.persistent = MICRODVD_PERSISTENT_ON; |
| tag.data1 = (*s++ == '1'); |
| if (*s != '}') |
| break; |
| tag.key = 'p'; |
| break; |
| |
| /* Coordinates */ |
| case 'o': |
| tag.persistent = MICRODVD_PERSISTENT_ON; |
| tag.data1 = strtol(s, &s, 10); |
| if (*s != ',') |
| break; |
| s++; |
| tag.data2 = strtol(s, &s, 10); |
| if (*s != '}') |
| break; |
| tag.key = 'o'; |
| break; |
| |
| default: /* Unknown tag, we consider it's text */ |
| break; |
| } |
| |
| if (tag.key == 0) |
| return start; |
| |
| microdvd_set_tag(tags, tag); |
| s++; |
| } |
| return check_for_italic_slash_marker(tags, s); |
| } |
| |
| static void microdvd_open_tags(AVBPrint *new_line, struct microdvd_tag *tags) |
| { |
| int i, sidx; |
| for (i = 0; i < sizeof(MICRODVD_TAGS) - 1; i++) { |
| if (tags[i].persistent == MICRODVD_PERSISTENT_OPENED) |
| continue; |
| switch (tags[i].key) { |
| case 'Y': |
| case 'y': |
| for (sidx = 0; sidx < sizeof(MICRODVD_STYLES) - 1; sidx++) |
| if (tags[i].data1 & (1 << sidx)) |
| av_bprintf(new_line, "{\\%c1}", MICRODVD_STYLES[sidx]); |
| break; |
| |
| case 'c': |
| av_bprintf(new_line, "{\\c&H%06X&}", tags[i].data1); |
| break; |
| |
| case 'f': |
| av_bprintf(new_line, "{\\fn%.*s}", |
| tags[i].data_string_len, tags[i].data_string); |
| break; |
| |
| case 's': |
| av_bprintf(new_line, "{\\fs%d}", tags[i].data1); |
| break; |
| |
| case 'p': |
| if (tags[i].data1 == 0) |
| av_bprintf(new_line, "{\\an8}"); |
| break; |
| |
| case 'o': |
| av_bprintf(new_line, "{\\pos(%d,%d)}", |
| tags[i].data1, tags[i].data2); |
| break; |
| } |
| if (tags[i].persistent == MICRODVD_PERSISTENT_ON) |
| tags[i].persistent = MICRODVD_PERSISTENT_OPENED; |
| } |
| } |
| |
| static void microdvd_close_no_persistent_tags(AVBPrint *new_line, |
| struct microdvd_tag *tags) |
| { |
| int i, sidx; |
| |
| for (i = sizeof(MICRODVD_TAGS) - 2; i >= 0; i--) { |
| if (tags[i].persistent != MICRODVD_PERSISTENT_OFF) |
| continue; |
| switch (tags[i].key) { |
| |
| case 'y': |
| for (sidx = sizeof(MICRODVD_STYLES) - 2; sidx >= 0; sidx--) |
| if (tags[i].data1 & (1 << sidx)) |
| av_bprintf(new_line, "{\\%c0}", MICRODVD_STYLES[sidx]); |
| break; |
| |
| case 'c': |
| av_bprintf(new_line, "{\\c}"); |
| break; |
| |
| case 'f': |
| av_bprintf(new_line, "{\\fn}"); |
| break; |
| |
| case 's': |
| av_bprintf(new_line, "{\\fs}"); |
| break; |
| } |
| tags[i].key = 0; |
| } |
| } |
| |
| static int microdvd_decode_frame(AVCodecContext *avctx, |
| void *data, int *got_sub_ptr, AVPacket *avpkt) |
| { |
| AVSubtitle *sub = data; |
| AVBPrint new_line; |
| char *line = avpkt->data; |
| char *end = avpkt->data + avpkt->size; |
| struct microdvd_tag tags[sizeof(MICRODVD_TAGS) - 1] = {{0}}; |
| |
| if (avpkt->size <= 0) |
| return avpkt->size; |
| |
| av_bprint_init(&new_line, 0, 2048); |
| |
| // subtitle content |
| while (line < end && *line) { |
| |
| // parse MicroDVD tags, and open them in ASS |
| line = microdvd_load_tags(tags, line); |
| microdvd_open_tags(&new_line, tags); |
| |
| // simple copy until EOL or forced carriage return |
| while (line < end && *line && *line != '|') { |
| av_bprint_chars(&new_line, *line, 1); |
| line++; |
| } |
| |
| // line split |
| if (line < end && *line == '|') { |
| microdvd_close_no_persistent_tags(&new_line, tags); |
| av_bprintf(&new_line, "\\N"); |
| line++; |
| } |
| } |
| if (new_line.len) { |
| int ret; |
| int64_t start = avpkt->pts; |
| int64_t duration = avpkt->duration; |
| int ts_start = av_rescale_q(start, avctx->time_base, (AVRational){1,100}); |
| int ts_duration = duration != -1 ? |
| av_rescale_q(duration, avctx->time_base, (AVRational){1,100}) : -1; |
| |
| ret = ff_ass_add_rect_bprint(sub, &new_line, ts_start, ts_duration); |
| av_bprint_finalize(&new_line, NULL); |
| if (ret < 0) |
| return ret; |
| } |
| |
| *got_sub_ptr = sub->num_rects > 0; |
| return avpkt->size; |
| } |
| |
| static int microdvd_init(AVCodecContext *avctx) |
| { |
| int i, sidx; |
| AVBPrint font_buf; |
| int font_size = ASS_DEFAULT_FONT_SIZE; |
| int color = ASS_DEFAULT_COLOR; |
| int bold = ASS_DEFAULT_BOLD; |
| int italic = ASS_DEFAULT_ITALIC; |
| int underline = ASS_DEFAULT_UNDERLINE; |
| int alignment = ASS_DEFAULT_ALIGNMENT; |
| struct microdvd_tag tags[sizeof(MICRODVD_TAGS) - 1] = {{0}}; |
| |
| av_bprint_init(&font_buf, 0, AV_BPRINT_SIZE_AUTOMATIC); |
| av_bprintf(&font_buf, "%s", ASS_DEFAULT_FONT); |
| |
| if (avctx->extradata) { |
| microdvd_load_tags(tags, avctx->extradata); |
| for (i = 0; i < sizeof(MICRODVD_TAGS) - 1; i++) { |
| switch (av_tolower(tags[i].key)) { |
| case 'y': |
| for (sidx = 0; sidx < sizeof(MICRODVD_STYLES) - 1; sidx++) { |
| if (tags[i].data1 & (1 << sidx)) { |
| switch (MICRODVD_STYLES[sidx]) { |
| case 'i': italic = 1; break; |
| case 'b': bold = 1; break; |
| case 'u': underline = 1; break; |
| } |
| } |
| } |
| break; |
| |
| case 'c': color = tags[i].data1; break; |
| case 's': font_size = tags[i].data1; break; |
| case 'p': alignment = 8; break; |
| |
| case 'f': |
| av_bprint_clear(&font_buf); |
| av_bprintf(&font_buf, "%.*s", |
| tags[i].data_string_len, tags[i].data_string); |
| break; |
| } |
| } |
| } |
| return ff_ass_subtitle_header(avctx, font_buf.str, font_size, color, |
| ASS_DEFAULT_BACK_COLOR, bold, italic, |
| underline, ASS_DEFAULT_BORDERSTYLE, |
| alignment); |
| } |
| |
| AVCodec ff_microdvd_decoder = { |
| .name = "microdvd", |
| .long_name = NULL_IF_CONFIG_SMALL("MicroDVD subtitle"), |
| .type = AVMEDIA_TYPE_SUBTITLE, |
| .id = AV_CODEC_ID_MICRODVD, |
| .init = microdvd_init, |
| .decode = microdvd_decode_frame, |
| }; |
