/* * DVD subtitle decoding * Copyright (c) 2005 Fabrice Bellard * * 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 */ #include <string.h> #include "libavutil/intreadwrite.h" #include "libavutil/mem.h" #include "avcodec.h" /* parser definition */ typedef struct DVDSubParseContext { uint8_t *packet; int packet_len; int packet_index; } DVDSubParseContext; static av_cold int dvdsub_parse_init(AVCodecParserContext *s) { return 0; } static int dvdsub_parse(AVCodecParserContext *s, AVCodecContext *avctx, const uint8_t **poutbuf, int *poutbuf_size, const uint8_t *buf, int buf_size) { DVDSubParseContext *pc = s->priv_data; if (pc->packet_index == 0) { if (buf_size < 2) return 0; pc->packet_len = AV_RB16(buf); if (pc->packet_len == 0) /* HD-DVD subpicture packet */ pc->packet_len = AV_RB32(buf+2); av_freep(&pc->packet); pc->packet = av_malloc(pc->packet_len); } if (pc->packet) { if (pc->packet_index + buf_size <= pc->packet_len) { memcpy(pc->packet + pc->packet_index, buf, buf_size); pc->packet_index += buf_size; if (pc->packet_index >= pc->packet_len) { *poutbuf = pc->packet; *poutbuf_size = pc->packet_len; pc->packet_index = 0; return buf_size; } } else { /* erroneous size */ pc->packet_index = 0; } } *poutbuf = NULL; *poutbuf_size = 0; return buf_size; } static av_cold void dvdsub_parse_close(AVCodecParserContext *s) { DVDSubParseContext *pc = s->priv_data; av_freep(&pc->packet); } AVCodecParser ff_dvdsub_parser = { .codec_ids = { AV_CODEC_ID_DVD_SUBTITLE }, .priv_data_size = sizeof(DVDSubParseContext), .parser_init = dvdsub_parse_init, .parser_parse = dvdsub_parse, .parser_close = dvdsub_parse_close, };