text: /*
   * SSA/ASS encoder
   * Copyright (c) 2010  Aurelien Jacobs <aurel@gnuage.org>
   *
   * This file is part of Libav.
   *
   * Libav 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.
   *
   * Libav 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 Libav; if not, write to the Free Software
   * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
   */
  
  #include "avcodec.h"
  #include "libavutil/avstring.h"
  
  static av_cold int ass_encode_init(AVCodecContext *avctx)
  {
      avctx->extradata = av_malloc(avctx->subtitle_header_size);
      if (!avctx->extradata)
          return AVERROR(ENOMEM);
      memcpy(avctx->extradata, avctx->subtitle_header, avctx->subtitle_header_size);
      avctx->extradata_size = avctx->subtitle_header_size;
      return 0;
  }
  
  static int ass_encode_frame(AVCodecContext *avctx,
                              unsigned char *buf, int bufsize, void *data)
  {
      AVSubtitle *sub = data;
      int i, len, total_len = 0;
  
      for (i=0; i<sub->num_rects; i++) {
          if (sub->rects[i]->type != SUBTITLE_ASS) {
              av_log(avctx, AV_LOG_ERROR, "Only SUBTITLE_ASS type supported.\n");
              return -1;
          }
  
          len = av_strlcpy(buf+total_len, sub->rects[i]->ass, bufsize-total_len);
  
          if (len > bufsize-total_len-1) {
              av_log(avctx, AV_LOG_ERROR, "Buffer too small for ASS event.\n");
              return -1;
          }
  
          total_len += len;
      }
  
      return total_len;
  }
  
  AVCodec ff_ass_encoder = {
      .name         = "ass",
      .long_name    = NULL_IF_CONFIG_SMALL("Advanced SubStation Alpha subtitle"),
      .type         = AVMEDIA_TYPE_SUBTITLE,
      .id           = CODEC_ID_SSA,
      .init         = ass_encode_init,
      .encode       = ass_encode_frame,
  };
  