2 * SubRip subtitle decoder
3 * Copyright (c) 2010 Aurelien Jacobs <aurel@gnuage.org>
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
22 #include "libavutil/avstring.h"
23 #include "libavutil/common.h"
24 #include "libavutil/intreadwrite.h"
25 #include "libavutil/parseutils.h"
29 static int html_color_parse(AVCodecContext *avctx, const char *str)
32 if (av_parse_color(rgba, str, strcspn(str, "\" >"), avctx) < 0)
34 return rgba[0] | rgba[1] << 8 | rgba[2] << 16;
45 typedef struct SrtStack {
47 char param[PARAM_NUMBER][128];
50 static void rstrip_spaces_buf(AVBPrint *buf)
52 while (buf->len > 0 && buf->str[buf->len - 1] == ' ')
53 buf->str[--buf->len] = 0;
56 static void srt_to_ass(AVCodecContext *avctx, AVBPrint *dst,
57 const char *in, int x1, int y1, int x2, int y2)
59 char *param, buffer[128], tmp[128];
60 int len, tag_close, sptr = 1, line_start = 1, an = 0, end = 0;
64 strcpy(stack[0].param[PARAM_SIZE], "{\\fs}");
65 strcpy(stack[0].param[PARAM_COLOR], "{\\c}");
66 strcpy(stack[0].param[PARAM_FACE], "{\\fn}");
68 if (x1 >= 0 && y1 >= 0) {
69 /* XXX: here we rescale coordinate assuming they are in DVD resolution
70 * (720x480) since we don't have anything better */
72 if (x2 >= 0 && y2 >= 0 && (x2 != x1 || y2 != y1) && x2 >= x1 && y2 >= y1) {
73 /* text rectangle defined, write the text at the center of the rectangle */
74 const int cx = x1 + (x2 - x1)/2;
75 const int cy = y1 + (y2 - y1)/2;
76 const int scaled_x = cx * ASS_DEFAULT_PLAYRESX / 720;
77 const int scaled_y = cy * ASS_DEFAULT_PLAYRESY / 480;
78 av_bprintf(dst, "{\\an5}{\\pos(%d,%d)}", scaled_x, scaled_y);
80 /* only the top left corner, assume the text starts in that corner */
81 const int scaled_x = x1 * ASS_DEFAULT_PLAYRESX / 720;
82 const int scaled_y = y1 * ASS_DEFAULT_PLAYRESY / 480;
83 av_bprintf(dst, "{\\an1}{\\pos(%d,%d)}", scaled_x, scaled_y);
87 for (; !end && *in; in++) {
96 rstrip_spaces_buf(dst);
97 av_bprintf(dst, "\\N");
102 av_bprint_chars(dst, *in, 1);
104 case '{': /* skip all {\xxx} substrings except for {\an%d}
105 and all microdvd like styles such as {Y:xxx} */
107 an += sscanf(in, "{\\an%*1u}%n", &len) >= 0 && len > 0;
108 if ((an != 1 && (len = 0, sscanf(in, "{\\%*[^}]}%n", &len) >= 0 && len > 0)) ||
109 (len = 0, sscanf(in, "{%*1[CcFfoPSsYy]:%*[^}]}%n", &len) >= 0 && len > 0)) {
112 av_bprint_chars(dst, *in, 1);
115 tag_close = in[1] == '/';
117 if (sscanf(in+tag_close+1, "%127[^>]>%n", buffer, &len) >= 1 && len > 0) {
118 if ((param = strchr(buffer, ' ')))
120 if ((!tag_close && sptr < FF_ARRAY_ELEMS(stack)) ||
121 ( tag_close && sptr > 0 && !strcmp(stack[sptr-1].tag, buffer))) {
122 int i, j, unknown = 0;
123 in += len + tag_close;
125 memset(stack+sptr, 0, sizeof(*stack));
126 if (!strcmp(buffer, "font")) {
128 for (i=PARAM_NUMBER-1; i>=0; i--)
129 if (stack[sptr-1].param[i][0])
130 for (j=sptr-2; j>=0; j--)
131 if (stack[j].param[i][0]) {
132 av_bprintf(dst, "%s", stack[j].param[i]);
137 if (!strncmp(param, "size=", 5)) {
139 param += 5 + (param[5] == '"');
140 if (sscanf(param, "%u", &font_size) == 1) {
141 snprintf(stack[sptr].param[PARAM_SIZE],
142 sizeof(stack[0].param[PARAM_SIZE]),
143 "{\\fs%u}", font_size);
145 } else if (!strncmp(param, "color=", 6)) {
146 param += 6 + (param[6] == '"');
147 snprintf(stack[sptr].param[PARAM_COLOR],
148 sizeof(stack[0].param[PARAM_COLOR]),
150 html_color_parse(avctx, param));
151 } else if (!strncmp(param, "face=", 5)) {
152 param += 5 + (param[5] == '"');
154 param[-1] == '"' ? "\"" :" ");
155 av_strlcpy(tmp, param,
156 FFMIN(sizeof(tmp), len+1));
158 snprintf(stack[sptr].param[PARAM_FACE],
159 sizeof(stack[0].param[PARAM_FACE]),
162 if ((param = strchr(param, ' ')))
165 for (i=0; i<PARAM_NUMBER; i++)
166 if (stack[sptr].param[i][0])
167 av_bprintf(dst, "%s", stack[sptr].param[i]);
169 } else if (!buffer[1] && strspn(buffer, "bisu") == 1) {
170 av_bprintf(dst, "{\\%c%d}", buffer[0], !tag_close);
173 snprintf(tmp, sizeof(tmp), "</%s>", buffer);
177 } else if (unknown && !strstr(in, tmp)) {
178 in -= len + tag_close;
179 av_bprint_chars(dst, *in, 1);
181 av_strlcpy(stack[sptr++].tag, buffer,
182 sizeof(stack[0].tag));
187 av_bprint_chars(dst, *in, 1);
190 if (*in != ' ' && *in != '\r' && *in != '\n')
194 while (dst->len >= 2 && !strncmp(&dst->str[dst->len - 2], "\\N", 2))
196 dst->str[dst->len] = 0;
197 rstrip_spaces_buf(dst);
200 static int srt_decode_frame(AVCodecContext *avctx,
201 void *data, int *got_sub_ptr, AVPacket *avpkt)
203 AVSubtitle *sub = data;
205 int ts_start, ts_end, x1 = -1, y1 = -1, x2 = -1, y2 = -1;
207 const uint8_t *p = av_packet_get_side_data(avpkt, AV_PKT_DATA_SUBTITLE_POSITION, &size);
209 if (p && size == 16) {
213 y2 = AV_RL32(p + 12);
216 if (avpkt->size <= 0)
219 av_bprint_init(&buffer, 0, AV_BPRINT_SIZE_UNLIMITED);
222 // Do final divide-by-10 outside rescale to force rounding down.
223 ts_start = av_rescale_q(avpkt->pts,
225 (AVRational){1,100});
226 ts_end = av_rescale_q(avpkt->pts + avpkt->duration,
228 (AVRational){1,100});
230 srt_to_ass(avctx, &buffer, avpkt->data, x1, y1, x2, y2);
231 ret = ff_ass_add_rect_bprint(sub, &buffer, ts_start, ts_end-ts_start);
232 av_bprint_finalize(&buffer, NULL);
236 *got_sub_ptr = sub->num_rects > 0;
240 #if CONFIG_SRT_DECODER
241 /* deprecated decoder */
242 AVCodec ff_srt_decoder = {
244 .long_name = NULL_IF_CONFIG_SMALL("SubRip subtitle"),
245 .type = AVMEDIA_TYPE_SUBTITLE,
246 .id = AV_CODEC_ID_SUBRIP,
247 .init = ff_ass_subtitle_header_default,
248 .decode = srt_decode_frame,
252 #if CONFIG_SUBRIP_DECODER
253 AVCodec ff_subrip_decoder = {
255 .long_name = NULL_IF_CONFIG_SMALL("SubRip subtitle"),
256 .type = AVMEDIA_TYPE_SUBTITLE,
257 .id = AV_CODEC_ID_SUBRIP,
258 .init = ff_ass_subtitle_header_default,
259 .decode = srt_decode_frame,