| /* |
| * SubRip subtitle demuxer |
| * Copyright (c) 2010 Aurelien Jacobs <aurel@gnuage.org> |
| * Copyright (c) 2015 Clément Bœsch <u pkh me> |
| * |
| * 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 "subtitles.h" |
| #include "libavutil/bprint.h" |
| #include "libavutil/intreadwrite.h" |
| |
| typedef struct { |
| FFDemuxSubtitlesQueue q; |
| } SRTContext; |
| |
| static int srt_probe(const AVProbeData *p) |
| { |
| int v; |
| char buf[64], *pbuf; |
| FFTextReader tr; |
| |
| ff_text_init_buf(&tr, p->buf, p->buf_size); |
| |
| while (ff_text_peek_r8(&tr) == '\r' || ff_text_peek_r8(&tr) == '\n') |
| ff_text_r8(&tr); |
| |
| /* Check if the first non-empty line is a number. We do not check what the |
| * number is because in practice it can be anything. |
| * Also, that number can be followed by random garbage, so we can not |
| * unfortunately check that we only have a number. */ |
| if (ff_subtitles_read_line(&tr, buf, sizeof(buf)) < 0 || |
| strtol(buf, &pbuf, 10) < 0 || pbuf == buf) |
| return 0; |
| |
| /* Check if the next line matches a SRT timestamp */ |
| if (ff_subtitles_read_line(&tr, buf, sizeof(buf)) < 0) |
| return 0; |
| pbuf = buf; |
| if (buf[0] == '-') |
| pbuf++; |
| if (pbuf[0] >= '0' && pbuf[0] <= '9' && strstr(buf, " --> ") |
| && sscanf(buf, "%*d:%*d:%*d%*1[,.]%*d --> %*d:%*d:%*d%*1[,.]%d", &v) == 1) |
| return AVPROBE_SCORE_MAX; |
| |
| return 0; |
| } |
| |
| struct event_info { |
| int32_t x1, x2, y1, y2; |
| int duration; |
| int64_t pts; |
| int64_t pos; |
| }; |
| |
| static int get_event_info(const char *line, struct event_info *ei) |
| { |
| int hh1, mm1, ss1, ms1; |
| int hh2, mm2, ss2, ms2; |
| |
| ei->x1 = ei->x2 = ei->y1 = ei->y2 = ei->duration = -1; |
| ei->pts = AV_NOPTS_VALUE; |
| ei->pos = -1; |
| if (sscanf(line, "%d:%d:%d%*1[,.]%d --> %d:%d:%d%*1[,.]%d" |
| "%*[ ]X1:%"PRId32" X2:%"PRId32" Y1:%"PRId32" Y2:%"PRId32, |
| &hh1, &mm1, &ss1, &ms1, |
| &hh2, &mm2, &ss2, &ms2, |
| &ei->x1, &ei->x2, &ei->y1, &ei->y2) >= 8) { |
| const int64_t start = (hh1*3600LL + mm1*60LL + ss1) * 1000LL + ms1; |
| const int64_t end = (hh2*3600LL + mm2*60LL + ss2) * 1000LL + ms2; |
| ei->duration = end - start; |
| ei->pts = start; |
| return 0; |
| } |
| return -1; |
| } |
| |
| static int add_event(FFDemuxSubtitlesQueue *q, AVBPrint *buf, char *line_cache, |
| const struct event_info *ei, int append_cache) |
| { |
| if (append_cache && line_cache[0]) |
| av_bprintf(buf, "%s\n", line_cache); |
| line_cache[0] = 0; |
| |
| while (buf->len > 0 && buf->str[buf->len - 1] == '\n') |
| buf->str[--buf->len] = 0; |
| |
| if (buf->len) { |
| AVPacket *sub = ff_subtitles_queue_insert(q, buf->str, buf->len, 0); |
| if (!sub) |
| return AVERROR(ENOMEM); |
| av_bprint_clear(buf); |
| sub->pos = ei->pos; |
| sub->pts = ei->pts; |
| sub->duration = ei->duration; |
| if (ei->x1 != -1) { |
| uint8_t *p = av_packet_new_side_data(sub, AV_PKT_DATA_SUBTITLE_POSITION, 16); |
| if (p) { |
| AV_WL32(p, ei->x1); |
| AV_WL32(p + 4, ei->y1); |
| AV_WL32(p + 8, ei->x2); |
| AV_WL32(p + 12, ei->y2); |
| } |
| } |
| } |
| |
| return 0; |
| } |
| |
| static int srt_read_header(AVFormatContext *s) |
| { |
| SRTContext *srt = s->priv_data; |
| AVBPrint buf; |
| AVStream *st = avformat_new_stream(s, NULL); |
| int res = 0; |
| char line[4096], line_cache[4096]; |
| int has_event_info = 0; |
| struct event_info ei; |
| FFTextReader tr; |
| ff_text_init_avio(s, &tr, s->pb); |
| |
| if (!st) |
| return AVERROR(ENOMEM); |
| avpriv_set_pts_info(st, 64, 1, 1000); |
| st->codecpar->codec_type = AVMEDIA_TYPE_SUBTITLE; |
| st->codecpar->codec_id = AV_CODEC_ID_SUBRIP; |
| |
| av_bprint_init(&buf, 0, AV_BPRINT_SIZE_UNLIMITED); |
| |
| line_cache[0] = 0; |
| |
| while (!ff_text_eof(&tr)) { |
| struct event_info tmp_ei; |
| const int64_t pos = ff_text_pos(&tr); |
| ptrdiff_t len = ff_subtitles_read_line(&tr, line, sizeof(line)); |
| |
| if (len < 0) |
| break; |
| |
| if (!len || !line[0]) |
| continue; |
| |
| if (get_event_info(line, &tmp_ei) < 0) { |
| char *pline; |
| |
| if (!has_event_info) |
| continue; |
| |
| if (line_cache[0]) { |
| /* We got some cache and a new line so we assume the cached |
| * line was actually part of the payload */ |
| av_bprintf(&buf, "%s\n", line_cache); |
| line_cache[0] = 0; |
| } |
| |
| /* If the line doesn't start with a number, we assume it's part of |
| * the payload, otherwise is likely an event number preceding the |
| * timing information... but we can't be sure of this yet, so we |
| * cache it */ |
| if (strtol(line, &pline, 10) < 0 || line == pline) |
| av_bprintf(&buf, "%s\n", line); |
| else |
| strcpy(line_cache, line); |
| } else { |
| if (has_event_info) { |
| /* We have the information of previous event, append it to the |
| * queue. We insert the cached line if and only if the payload |
| * is empty and the cached line is not a standalone number. */ |
| char *pline = NULL; |
| const int standalone_number = strtol(line_cache, &pline, 10) >= 0 && pline && !*pline; |
| res = add_event(&srt->q, &buf, line_cache, &ei, !buf.len && !standalone_number); |
| if (res < 0) |
| goto end; |
| } else { |
| has_event_info = 1; |
| } |
| tmp_ei.pos = pos; |
| ei = tmp_ei; |
| } |
| } |
| |
| /* Append the last event. Here we force the cache to be flushed, because a |
| * trailing number is more likely to be geniune (for example a copyright |
| * date) and not the event index of an inexistant event */ |
| if (has_event_info) { |
| res = add_event(&srt->q, &buf, line_cache, &ei, 1); |
| if (res < 0) |
| goto end; |
| } |
| |
| ff_subtitles_queue_finalize(s, &srt->q); |
| |
| end: |
| if (res < 0) |
| ff_subtitles_queue_clean(&srt->q); |
| av_bprint_finalize(&buf, NULL); |
| return res; |
| } |
| |
| static int srt_read_packet(AVFormatContext *s, AVPacket *pkt) |
| { |
| SRTContext *srt = s->priv_data; |
| return ff_subtitles_queue_read_packet(&srt->q, pkt); |
| } |
| |
| static int srt_read_seek(AVFormatContext *s, int stream_index, |
| int64_t min_ts, int64_t ts, int64_t max_ts, int flags) |
| { |
| SRTContext *srt = s->priv_data; |
| return ff_subtitles_queue_seek(&srt->q, s, stream_index, |
| min_ts, ts, max_ts, flags); |
| } |
| |
| static int srt_read_close(AVFormatContext *s) |
| { |
| SRTContext *srt = s->priv_data; |
| ff_subtitles_queue_clean(&srt->q); |
| return 0; |
| } |
| |
| AVInputFormat ff_srt_demuxer = { |
| .name = "srt", |
| .long_name = NULL_IF_CONFIG_SMALL("SubRip subtitle"), |
| .priv_data_size = sizeof(SRTContext), |
| .read_probe = srt_probe, |
| .read_header = srt_read_header, |
| .read_packet = srt_read_packet, |
| .read_seek2 = srt_read_seek, |
| .read_close = srt_read_close, |
| }; |