| /* | |
| * 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 "demux.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; | |
| if (!av_bprint_is_complete(buf)) | |
| return AVERROR(ENOMEM); | |
| while (buf->len > 0 && buf->str[buf->len - 1] == '\n') | |
| buf->str[--buf->len] = 0; | |
| if (buf->len) { | |
| AVPacket *sub = ff_subtitles_queue_insert_bprint(q, buf, 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: | |
| av_bprint_finalize(&buf, NULL); | |
| return res; | |
| } | |
| const FFInputFormat ff_srt_demuxer = { | |
| .p.name = "srt", | |
| .p.long_name = NULL_IF_CONFIG_SMALL("SubRip subtitle"), | |
| .priv_data_size = sizeof(SRTContext), | |
| .flags_internal = FF_INFMT_FLAG_INIT_CLEANUP, | |
| .read_probe = srt_probe, | |
| .read_header = srt_read_header, | |
| .read_packet = ff_subtitles_read_packet, | |
| .read_seek2 = ff_subtitles_read_seek, | |
| .read_close = ff_subtitles_read_close, | |
| }; |