yading@10: /*
yading@10:  * SSA/ASS decoder
yading@10:  * Copyright (c) 2010  Aurelien Jacobs <aurel@gnuage.org>
yading@10:  *
yading@10:  * This file is part of FFmpeg.
yading@10:  *
yading@10:  * FFmpeg is free software; you can redistribute it and/or
yading@10:  * modify it under the terms of the GNU Lesser General Public
yading@10:  * License as published by the Free Software Foundation; either
yading@10:  * version 2.1 of the License, or (at your option) any later version.
yading@10:  *
yading@10:  * FFmpeg is distributed in the hope that it will be useful,
yading@10:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@10:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@10:  * Lesser General Public License for more details.
yading@10:  *
yading@10:  * You should have received a copy of the GNU Lesser General Public
yading@10:  * License along with FFmpeg; if not, write to the Free Software
yading@10:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@10:  */
yading@10: 
yading@10: #include <string.h>
yading@10: 
yading@10: #include "avcodec.h"
yading@10: #include "ass.h"
yading@10: #include "ass_split.h"
yading@10: #include "libavutil/internal.h"
yading@10: #include "libavutil/mem.h"
yading@10: 
yading@10: static av_cold int ass_decode_init(AVCodecContext *avctx)
yading@10: {
yading@10:     avctx->subtitle_header = av_malloc(avctx->extradata_size + 1);
yading@10:     if (!avctx->subtitle_header)
yading@10:         return AVERROR(ENOMEM);
yading@10:     memcpy(avctx->subtitle_header, avctx->extradata, avctx->extradata_size);
yading@10:     avctx->subtitle_header[avctx->extradata_size] = 0;
yading@10:     avctx->subtitle_header_size = avctx->extradata_size;
yading@10:     avctx->priv_data = ff_ass_split(avctx->extradata);
yading@10:     if(!avctx->priv_data)
yading@10:         return -1;
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: static int ass_decode_close(AVCodecContext *avctx)
yading@10: {
yading@10:     ff_ass_split_free(avctx->priv_data);
yading@10:     avctx->priv_data = NULL;
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: #if CONFIG_SSA_DECODER
yading@10: static int ssa_decode_frame(AVCodecContext *avctx, void *data, int *got_sub_ptr,
yading@10:                             AVPacket *avpkt)
yading@10: {
yading@10:     const char *ptr = avpkt->data;
yading@10:     int len, size = avpkt->size;
yading@10: 
yading@10:     while (size > 0) {
yading@10:         int duration;
yading@10:         ASSDialog *dialog = ff_ass_split_dialog(avctx->priv_data, ptr, 0, NULL);
yading@10:         if (!dialog)
yading@10:             return AVERROR_INVALIDDATA;
yading@10:         duration = dialog->end - dialog->start;
yading@10:         len = ff_ass_add_rect(data, ptr, 0, duration, 1);
yading@10:         if (len < 0)
yading@10:             return len;
yading@10:         ptr  += len;
yading@10:         size -= len;
yading@10:     }
yading@10: 
yading@10:     *got_sub_ptr = avpkt->size > 0;
yading@10:     return avpkt->size;
yading@10: }
yading@10: 
yading@10: AVCodec ff_ssa_decoder = {
yading@10:     .name         = "ssa",
yading@10:     .long_name    = NULL_IF_CONFIG_SMALL("SSA (SubStation Alpha) subtitle"),
yading@10:     .type         = AVMEDIA_TYPE_SUBTITLE,
yading@10:     .id           = AV_CODEC_ID_SSA,
yading@10:     .init         = ass_decode_init,
yading@10:     .decode       = ssa_decode_frame,
yading@10:     .close        = ass_decode_close,
yading@10: };
yading@10: #endif
yading@10: 
yading@10: #if CONFIG_ASS_DECODER
yading@10: static int ass_decode_frame(AVCodecContext *avctx, void *data, int *got_sub_ptr,
yading@10:                             AVPacket *avpkt)
yading@10: {
yading@10:     int ret;
yading@10:     AVSubtitle *sub = data;
yading@10:     const char *ptr = avpkt->data;
yading@10:     static const AVRational ass_tb = {1, 100};
yading@10:     const int ts_start    = av_rescale_q(avpkt->pts,      avctx->time_base, ass_tb);
yading@10:     const int ts_duration = av_rescale_q(avpkt->duration, avctx->time_base, ass_tb);
yading@10: 
yading@10:     if (avpkt->size <= 0)
yading@10:         return avpkt->size;
yading@10: 
yading@10:     ret = ff_ass_add_rect(sub, ptr, ts_start, ts_duration, 2);
yading@10:     if (ret < 0) {
yading@10:         if (ret == AVERROR_INVALIDDATA)
yading@10:             av_log(avctx, AV_LOG_ERROR, "Invalid ASS packet\n");
yading@10:         return ret;
yading@10:     }
yading@10: 
yading@10:     *got_sub_ptr = avpkt->size > 0;
yading@10:     return avpkt->size;
yading@10: }
yading@10: 
yading@10: AVCodec ff_ass_decoder = {
yading@10:     .name         = "ass",
yading@10:     .long_name    = NULL_IF_CONFIG_SMALL("ASS (Advanced SubStation Alpha) subtitle"),
yading@10:     .type         = AVMEDIA_TYPE_SUBTITLE,
yading@10:     .id           = AV_CODEC_ID_ASS,
yading@10:     .init         = ass_decode_init,
yading@10:     .decode       = ass_decode_frame,
yading@10:     .close        = ass_decode_close,
yading@10: };
yading@10: #endif