1/* 2 * SubRip subtitle encoder 3 * Copyright (c) 2010 Aurelien Jacobs <aurel@gnuage.org> 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#include <stdarg.h> 23#include "avcodec.h" 24#include "libavutil/avstring.h" 25#include "libavutil/bprint.h" 26#include "ass_split.h" 27#include "ass.h" 28 29 30#define SRT_STACK_SIZE 64 31 32typedef struct { 33 AVCodecContext *avctx; 34 ASSSplitContext *ass_ctx; 35 AVBPrint buffer; 36 unsigned timestamp_end; 37 int count; 38 char stack[SRT_STACK_SIZE]; 39 int stack_ptr; 40 int alignment_applied; 41} SRTContext; 42 43 44#ifdef __GNUC__ 45__attribute__ ((__format__ (__printf__, 2, 3))) 46#endif 47static void srt_print(SRTContext *s, const char *str, ...) 48{ 49 va_list vargs; 50 va_start(vargs, str); 51 av_vbprintf(&s->buffer, str, vargs); 52 va_end(vargs); 53} 54 55static int srt_stack_push(SRTContext *s, const char c) 56{ 57 if (s->stack_ptr >= SRT_STACK_SIZE) 58 return -1; 59 s->stack[s->stack_ptr++] = c; 60 return 0; 61} 62 63static char srt_stack_pop(SRTContext *s) 64{ 65 if (s->stack_ptr <= 0) 66 return 0; 67 return s->stack[--s->stack_ptr]; 68} 69 70static int srt_stack_find(SRTContext *s, const char c) 71{ 72 int i; 73 for (i = s->stack_ptr-1; i >= 0; i--) 74 if (s->stack[i] == c) 75 break; 76 return i; 77} 78 79static void srt_close_tag(SRTContext *s, char tag) 80{ 81 srt_print(s, "</%c%s>", tag, tag == 'f' ? "ont" : ""); 82} 83 84static void srt_stack_push_pop(SRTContext *s, const char c, int close) 85{ 86 if (close) { 87 int i = c ? srt_stack_find(s, c) : 0; 88 if (i < 0) 89 return; 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"); 94} 95 96static void srt_style_apply(SRTContext *s, const char *style) 97{ 98 ASSStyle *st = ff_ass_style_get(s->ass_ctx, style); 99 if (st) { 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); 112 srt_print(s, ">"); 113 srt_stack_push(s, 'f'); 114 } 115 if (st->bold != ASS_DEFAULT_BOLD) { 116 srt_print(s, "<b>"); 117 srt_stack_push(s, 'b'); 118 } 119 if (st->italic != ASS_DEFAULT_ITALIC) { 120 srt_print(s, "<i>"); 121 srt_stack_push(s, 'i'); 122 } 123 if (st->underline != ASS_DEFAULT_UNDERLINE) { 124 srt_print(s, "<u>"); 125 srt_stack_push(s, 'u'); 126 } 127 if (st->alignment != ASS_DEFAULT_ALIGNMENT) { 128 srt_print(s, "{\\an%d}", st->alignment); 129 s->alignment_applied = 1; 130 } 131 } 132} 133 134 135static av_cold int srt_encode_init(AVCodecContext *avctx) 136{ 137 SRTContext *s = avctx->priv_data; 138 s->avctx = avctx; 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; 142} 143 144static void srt_text_cb(void *priv, const char *text, int len) 145{ 146 SRTContext *s = priv; 147 av_bprint_append_data(&s->buffer, text, len); 148} 149 150static void srt_new_line_cb(void *priv, int forced) 151{ 152 srt_print(priv, "\r\n"); 153} 154 155static void srt_style_cb(void *priv, char style, int close) 156{ 157 srt_stack_push_pop(priv, style, close); 158 if (!close) 159 srt_print(priv, "<%c>", style); 160} 161 162static void srt_color_cb(void *priv, unsigned int color, unsigned int color_id) 163{ 164 if (color_id > 1) 165 return; 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); 170} 171 172static void srt_font_name_cb(void *priv, const char *name) 173{ 174 srt_stack_push_pop(priv, 'f', !name); 175 if (name) 176 srt_print(priv, "<font face=\"%s\">", name); 177} 178 179static void srt_font_size_cb(void *priv, int size) 180{ 181 srt_stack_push_pop(priv, 'f', size < 0); 182 if (size >= 0) 183 srt_print(priv, "<font size=\"%d\">", size); 184} 185 186static void srt_alignment_cb(void *priv, int alignment) 187{ 188 SRTContext *s = priv; 189 if (!s->alignment_applied && alignment >= 0) { 190 srt_print(s, "{\\an%d}", alignment); 191 s->alignment_applied = 1; 192 } 193} 194 195static void srt_cancel_overrides_cb(void *priv, const char *style) 196{ 197 srt_stack_push_pop(priv, 0, 1); 198 srt_style_apply(priv, style); 199} 200 201static void srt_move_cb(void *priv, int x1, int y1, int x2, int y2, 202 int t1, int t2) 203{ 204 SRTContext *s = priv; 205 206 if (s->avctx->codec->id == AV_CODEC_ID_SRT) { 207 char buffer[32]; 208 int len = snprintf(buffer, sizeof(buffer), 209 " X1:%03u X2:%03u Y1:%03u Y2:%03u", x1, x2, y1, y2); 210 unsigned char *dummy; 211 unsigned room; 212 213 av_bprint_get_buffer(&s->buffer, len, &dummy, &room); 214 if (room >= len) { 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); 219 } 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; 223 } 224} 225 226static void srt_end_cb(void *priv) 227{ 228 SRTContext *s = priv; 229 230 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"); 233} 234 235static const ASSCodesCallbacks srt_callbacks = { 236 .text = srt_text_cb, 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, 244 .move = srt_move_cb, 245 .end = srt_end_cb, 246}; 247 248static int srt_encode_frame(AVCodecContext *avctx, 249 unsigned char *buf, int bufsize, const AVSubtitle *sub) 250{ 251 SRTContext *s = avctx->priv_data; 252 ASSDialog *dialog; 253 int i, num; 254 255 av_bprint_clear(&s->buffer); 256 257 for (i=0; i<sub->num_rects; i++) { 258 259 if (sub->rects[i]->type != SUBTITLE_ASS) { 260 av_log(avctx, AV_LOG_ERROR, "Only SUBTITLE_ASS type supported.\n"); 261 return AVERROR(ENOSYS); 262 } 263 264 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; 278 } 279 s->alignment_applied = 0; 280 srt_style_apply(s, dialog->style); 281 ff_ass_split_override_codes(&srt_callbacks, s, dialog->text); 282 } 283 } 284 285 if (!av_bprint_is_complete(&s->buffer)) 286 return AVERROR(ENOMEM); 287 if (!s->buffer.len) 288 return 0; 289 290 if (s->buffer.len > bufsize) { 291 av_log(avctx, AV_LOG_ERROR, "Buffer too small for ASS event.\n"); 292 return -1; 293 } 294 memcpy(buf, s->buffer.str, s->buffer.len); 295 296 return s->buffer.len; 297} 298 299static int srt_encode_close(AVCodecContext *avctx) 300{ 301 SRTContext *s = avctx->priv_data; 302 ff_ass_split_free(s->ass_ctx); 303 av_bprint_finalize(&s->buffer, NULL); 304 return 0; 305} 306 307#if CONFIG_SRT_ENCODER 308/* deprecated encoder */ 309AVCodec ff_srt_encoder = { 310 .name = "srt", 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, 318}; 319#endif 320 321#if CONFIG_SUBRIP_ENCODER 322AVCodec ff_subrip_encoder = { 323 .name = "subrip", 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, 331}; 332#endif 333