/* * SubRip subtitle muxer * Copyright (c) 2012 Nicolas George <nicolas.george@normalesup.org> * * 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 "avformat.h" #include "internal.h" #include "libavutil/log.h" #include "libavutil/intreadwrite.h" /* TODO: add options for: - character encoding; - LF / CRLF; - byte order mark. */ typedef struct SRTContext{ unsigned index; } SRTContext; static int srt_write_header(AVFormatContext *avf) { SRTContext *srt = avf->priv_data; if (avf->nb_streams != 1 || avf->streams[0]->codec->codec_type != AVMEDIA_TYPE_SUBTITLE) { av_log(avf, AV_LOG_ERROR, "SRT supports only a single subtitles stream.\n"); return AVERROR(EINVAL); } if (avf->streams[0]->codec->codec_id != AV_CODEC_ID_TEXT && avf->streams[0]->codec->codec_id != AV_CODEC_ID_SUBRIP && avf->streams[0]->codec->codec_id != AV_CODEC_ID_SRT) { av_log(avf, AV_LOG_ERROR, "Unsupported subtitles codec: %s\n", avcodec_get_name(avf->streams[0]->codec->codec_id)); return AVERROR(EINVAL); } avpriv_set_pts_info(avf->streams[0], 64, 1, 1000); srt->index = 1; return 0; } static int srt_write_packet(AVFormatContext *avf, AVPacket *pkt) { SRTContext *srt = avf->priv_data; int write_ts = avf->streams[0]->codec->codec_id != AV_CODEC_ID_SRT; if (write_ts) { int64_t s = pkt->pts, e, d = pkt->duration; int size, x1 = -1, y1 = -1, x2 = -1, y2 = -1; const uint8_t *p; p = av_packet_get_side_data(pkt, AV_PKT_DATA_SUBTITLE_POSITION, &size); if (p && size == 16) { x1 = AV_RL32(p ); y1 = AV_RL32(p + 4); x2 = AV_RL32(p + 8); y2 = AV_RL32(p + 12); } if (d <= 0) /* For backward compatibility, fallback to convergence_duration. */ d = pkt->convergence_duration; if (s == AV_NOPTS_VALUE || d < 0) { av_log(avf, AV_LOG_WARNING, "Insufficient timestamps in event number %d.\n", srt->index); return 0; } e = s + d; avio_printf(avf->pb, "%d\n%02d:%02d:%02d,%03d --> %02d:%02d:%02d,%03d", srt->index, (int)(s / 3600000), (int)(s / 60000) % 60, (int)(s / 1000) % 60, (int)(s % 1000), (int)(e / 3600000), (int)(e / 60000) % 60, (int)(e / 1000) % 60, (int)(e % 1000)); if (p) avio_printf(avf->pb, " X1:%03d X2:%03d Y1:%03d Y2:%03d", x1, x2, y1, y2); avio_printf(avf->pb, "\n"); } avio_write(avf->pb, pkt->data, pkt->size); if (write_ts) avio_write(avf->pb, "\n\n", 2); srt->index++; return 0; } AVOutputFormat ff_srt_muxer = { .name = "srt", .long_name = NULL_IF_CONFIG_SMALL("SubRip subtitle"), .mime_type = "application/x-subrip", .extensions = "srt", .priv_data_size = sizeof(SRTContext), .write_header = srt_write_header, .write_packet = srt_write_packet, .flags = AVFMT_VARIABLE_FPS | AVFMT_TS_NONSTRICT, .subtitle_codec = AV_CODEC_ID_SUBRIP, };