diff options
Diffstat (limited to 'libavformat/srtdec.c')
-rw-r--r-- | libavformat/srtdec.c | 240 |
1 files changed, 191 insertions, 49 deletions
diff --git a/libavformat/srtdec.c b/libavformat/srtdec.c index 6f8206c755..067db63f21 100644 --- a/libavformat/srtdec.c +++ b/libavformat/srtdec.c @@ -1,102 +1,244 @@ /* * SubRip subtitle demuxer * Copyright (c) 2010 Aurelien Jacobs <aurel@gnuage.org> + * Copyright (c) 2015 Clément Bœsch <u pkh me> * - * This file is part of Libav. + * This file is part of FFmpeg. * - * Libav is free software; you can redistribute it and/or + * 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. * - * Libav is distributed in the hope that it will be useful, + * 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 Libav; if not, write to the Free Software + * 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(AVProbeData *p) { - unsigned char *ptr = p->buf; - int i, v, num = 0; + 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:%u X2:%u Y1:%u Y2:%u", + &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_RB24(ptr) == 0xEFBBBF) - ptr += 3; /* skip UTF-8 BOM */ + while (buf->len > 0 && buf->str[buf->len - 1] == '\n') + buf->str[--buf->len] = 0; - for (i=0; i<2; i++) { - if (num == i && sscanf(ptr, "%*d:%*2d:%*2d%*1[,.]%*3d --> %*d:%*2d:%*2d%*1[,.]%3d", &v) == 1) - return AVPROBE_SCORE_MAX; - num = atoi(ptr); - ptr += strcspn(ptr, "\n") + 1; + 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 -1; + 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_SRT; - return 0; -} + st->codecpar->codec_id = AV_CODEC_ID_SUBRIP; -static int64_t get_pts(const char *buf) -{ - int i, v, hour, min, sec, hsec; - - for (i=0; i<2; i++) { - if (sscanf(buf, "%d:%2d:%2d%*1[,.]%3d --> %*d:%*2d:%*2d%*1[,.]%3d", - &hour, &min, &sec, &hsec, &v) == 5) { - min += 60*hour; - sec += 60*min; - return sec*1000+hsec; + 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; } - buf += strcspn(buf, "\n") + 1; } - return AV_NOPTS_VALUE; + + /* 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; } -static inline int is_eol(char c) +static int srt_read_packet(AVFormatContext *s, AVPacket *pkt) { - return c == '\r' || c == '\n'; + SRTContext *srt = s->priv_data; + return ff_subtitles_queue_read_packet(&srt->q, pkt); } -static int srt_read_packet(AVFormatContext *s, AVPacket *pkt) +static int srt_read_seek(AVFormatContext *s, int stream_index, + int64_t min_ts, int64_t ts, int64_t max_ts, int flags) { - char buffer[2048], *ptr = buffer, *ptr2; - int64_t pos = avio_tell(s->pb); - int res = AVERROR_EOF; - - do { - ptr2 = ptr; - ptr += ff_get_line(s->pb, ptr, sizeof(buffer)+buffer-ptr); - } while (!is_eol(*ptr2) && !s->pb->eof_reached && ptr-buffer<sizeof(buffer)-1); - - if (buffer[0] && !(res = av_new_packet(pkt, ptr-buffer))) { - memcpy(pkt->data, buffer, pkt->size); - pkt->flags |= AV_PKT_FLAG_KEY; - pkt->pos = pos; - pkt->pts = pkt->dts = get_pts(pkt->data); - } - return res; + 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, - .flags = AVFMT_GENERIC_INDEX, + .read_seek2 = srt_read_seek, + .read_close = srt_read_close, }; |