2 * SubRip subtitle encoder
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
24 #include "libavutil/avstring.h"
25 #include "libavutil/bprint.h"
26 #include "ass_split.h"
30 #define SRT_STACK_SIZE 64
33 AVCodecContext *avctx;
34 ASSSplitContext *ass_ctx;
36 unsigned timestamp_end;
38 char stack[SRT_STACK_SIZE];
40 int alignment_applied;
45 __attribute__ ((__format__ (__printf__, 2, 3)))
47 static void srt_print(SRTContext *s, const char *str, ...)
51 av_vbprintf(&s->buffer, str, vargs);
55 static int srt_stack_push(SRTContext *s, const char c)
57 if (s->stack_ptr >= SRT_STACK_SIZE)
59 s->stack[s->stack_ptr++] = c;
63 static char srt_stack_pop(SRTContext *s)
65 if (s->stack_ptr <= 0)
67 return s->stack[--s->stack_ptr];
70 static int srt_stack_find(SRTContext *s, const char c)
73 for (i = s->stack_ptr-1; i >= 0; i--)
79 static void srt_close_tag(SRTContext *s, char tag)
81 srt_print(s, "</%c%s>", tag, tag == 'f' ? "ont" : "");
84 static void srt_stack_push_pop(SRTContext *s, const char c, int close)
87 int i = c ? srt_stack_find(s, c) : 0;
90 while (s->stack_ptr != i)
91 srt_close_tag(s, srt_stack_pop(s));
92 } else if (srt_stack_push(s, c) < 0)
93 av_log(s->avctx, AV_LOG_ERROR, "tag stack overflow\n");
96 static void srt_style_apply(SRTContext *s, const char *style)
98 ASSStyle *st = ff_ass_style_get(s->ass_ctx, style);
100 int c = st->primary_color & 0xFFFFFF;
101 if (st->font_name && strcmp(st->font_name, ASS_DEFAULT_FONT) ||
102 st->font_size != ASS_DEFAULT_FONT_SIZE ||
103 c != ASS_DEFAULT_COLOR) {
104 srt_print(s, "<font");
105 if (st->font_name && strcmp(st->font_name, ASS_DEFAULT_FONT))
106 srt_print(s, " face=\"%s\"", st->font_name);
107 if (st->font_size != ASS_DEFAULT_FONT_SIZE)
108 srt_print(s, " size=\"%d\"", st->font_size);
109 if (c != ASS_DEFAULT_COLOR)
110 srt_print(s, " color=\"#%06x\"",
111 (c & 0xFF0000) >> 16 | c & 0xFF00 | (c & 0xFF) << 16);
113 srt_stack_push(s, 'f');
115 if (st->bold != ASS_DEFAULT_BOLD) {
117 srt_stack_push(s, 'b');
119 if (st->italic != ASS_DEFAULT_ITALIC) {
121 srt_stack_push(s, 'i');
123 if (st->underline != ASS_DEFAULT_UNDERLINE) {
125 srt_stack_push(s, 'u');
127 if (st->alignment != ASS_DEFAULT_ALIGNMENT) {
128 srt_print(s, "{\\an%d}", st->alignment);
129 s->alignment_applied = 1;
135 static av_cold int srt_encode_init(AVCodecContext *avctx)
137 SRTContext *s = avctx->priv_data;
139 s->ass_ctx = ff_ass_split(avctx->subtitle_header);
140 av_bprint_init(&s->buffer, 0, AV_BPRINT_SIZE_UNLIMITED);
141 return s->ass_ctx ? 0 : AVERROR_INVALIDDATA;
144 static void srt_text_cb(void *priv, const char *text, int len)
146 SRTContext *s = priv;
147 av_bprint_append_data(&s->buffer, text, len);
150 static void srt_new_line_cb(void *priv, int forced)
152 srt_print(priv, "\r\n");
155 static void srt_style_cb(void *priv, char style, int close)
157 srt_stack_push_pop(priv, style, close);
159 srt_print(priv, "<%c>", style);
162 static void srt_color_cb(void *priv, unsigned int color, unsigned int color_id)
166 srt_stack_push_pop(priv, 'f', color == 0xFFFFFFFF);
167 if (color != 0xFFFFFFFF)
168 srt_print(priv, "<font color=\"#%06x\">",
169 (color & 0xFF0000) >> 16 | color & 0xFF00 | (color & 0xFF) << 16);
172 static void srt_font_name_cb(void *priv, const char *name)
174 srt_stack_push_pop(priv, 'f', !name);
176 srt_print(priv, "<font face=\"%s\">", name);
179 static void srt_font_size_cb(void *priv, int size)
181 srt_stack_push_pop(priv, 'f', size < 0);
183 srt_print(priv, "<font size=\"%d\">", size);
186 static void srt_alignment_cb(void *priv, int alignment)
188 SRTContext *s = priv;
189 if (!s->alignment_applied && alignment >= 0) {
190 srt_print(s, "{\\an%d}", alignment);
191 s->alignment_applied = 1;
195 static void srt_cancel_overrides_cb(void *priv, const char *style)
197 srt_stack_push_pop(priv, 0, 1);
198 srt_style_apply(priv, style);
201 static void srt_move_cb(void *priv, int x1, int y1, int x2, int y2,
204 SRTContext *s = priv;
206 if (s->avctx->codec->id == AV_CODEC_ID_SRT) {
208 int len = snprintf(buffer, sizeof(buffer),
209 " X1:%03u X2:%03u Y1:%03u Y2:%03u", x1, x2, y1, y2);
210 unsigned char *dummy;
213 av_bprint_get_buffer(&s->buffer, len, &dummy, &room);
215 memmove(s->buffer.str + s->timestamp_end + len,
216 s->buffer.str + s->timestamp_end,
217 s->buffer.len - s->timestamp_end + 1);
218 memcpy(s->buffer.str + s->timestamp_end, buffer, len);
220 /* Increment even if av_bprint_get_buffer() did not return enough room:
221 the bprint structure will be treated as truncated. */
222 s->buffer.len += len;
226 static void srt_end_cb(void *priv)
228 SRTContext *s = priv;
230 srt_stack_push_pop(priv, 0, 1);
231 if (s->avctx->codec->id == AV_CODEC_ID_SRT)
232 srt_print(priv, "\r\n\r\n");
235 static const ASSCodesCallbacks srt_callbacks = {
237 .new_line = srt_new_line_cb,
238 .style = srt_style_cb,
239 .color = srt_color_cb,
240 .font_name = srt_font_name_cb,
241 .font_size = srt_font_size_cb,
242 .alignment = srt_alignment_cb,
243 .cancel_overrides = srt_cancel_overrides_cb,
248 static int srt_encode_frame(AVCodecContext *avctx,
249 unsigned char *buf, int bufsize, const AVSubtitle *sub)
251 SRTContext *s = avctx->priv_data;
255 av_bprint_clear(&s->buffer);
257 for (i=0; i<sub->num_rects; i++) {
259 if (sub->rects[i]->type != SUBTITLE_ASS) {
260 av_log(avctx, AV_LOG_ERROR, "Only SUBTITLE_ASS type supported.\n");
261 return AVERROR(ENOSYS);
264 dialog = ff_ass_split_dialog(s->ass_ctx, sub->rects[i]->ass, 0, &num);
265 for (; dialog && num--; dialog++) {
266 if (avctx->codec->id == AV_CODEC_ID_SRT) {
267 int sh, sm, ss, sc = 10 * dialog->start;
268 int eh, em, es, ec = 10 * dialog->end;
269 sh = sc/3600000; sc -= 3600000*sh;
270 sm = sc/ 60000; sc -= 60000*sm;
271 ss = sc/ 1000; sc -= 1000*ss;
272 eh = ec/3600000; ec -= 3600000*eh;
273 em = ec/ 60000; ec -= 60000*em;
274 es = ec/ 1000; ec -= 1000*es;
275 srt_print(s,"%d\r\n%02d:%02d:%02d,%03d --> %02d:%02d:%02d,%03d\r\n",
276 ++s->count, sh, sm, ss, sc, eh, em, es, ec);
277 s->timestamp_end = s->buffer.len - 2;
279 s->alignment_applied = 0;
280 srt_style_apply(s, dialog->style);
281 ff_ass_split_override_codes(&srt_callbacks, s, dialog->text);
285 if (!av_bprint_is_complete(&s->buffer))
286 return AVERROR(ENOMEM);
290 if (s->buffer.len > bufsize) {
291 av_log(avctx, AV_LOG_ERROR, "Buffer too small for ASS event.\n");
294 memcpy(buf, s->buffer.str, s->buffer.len);
296 return s->buffer.len;
299 static int srt_encode_close(AVCodecContext *avctx)
301 SRTContext *s = avctx->priv_data;
302 ff_ass_split_free(s->ass_ctx);
303 av_bprint_finalize(&s->buffer, NULL);
307 #if CONFIG_SRT_ENCODER
308 /* deprecated encoder */
309 AVCodec ff_srt_encoder = {
311 .long_name = NULL_IF_CONFIG_SMALL("SubRip subtitle with embedded timing"),
312 .type = AVMEDIA_TYPE_SUBTITLE,
313 .id = AV_CODEC_ID_SRT,
314 .priv_data_size = sizeof(SRTContext),
315 .init = srt_encode_init,
316 .encode_sub = srt_encode_frame,
317 .close = srt_encode_close,
321 #if CONFIG_SUBRIP_ENCODER
322 AVCodec ff_subrip_encoder = {
324 .long_name = NULL_IF_CONFIG_SMALL("SubRip subtitle"),
325 .type = AVMEDIA_TYPE_SUBTITLE,
326 .id = AV_CODEC_ID_SUBRIP,
327 .priv_data_size = sizeof(SRTContext),
328 .init = srt_encode_init,
329 .encode_sub = srt_encode_frame,
330 .close = srt_encode_close,