diff options
Diffstat (limited to 'libavformat/subviewerdec.c')
| -rw-r--r-- | libavformat/subviewerdec.c | 194 |
1 files changed, 194 insertions, 0 deletions
diff --git a/libavformat/subviewerdec.c b/libavformat/subviewerdec.c new file mode 100644 index 0000000..9e645d2 --- /dev/null +++ b/libavformat/subviewerdec.c @@ -0,0 +1,194 @@ +/* + * Copyright (c) 2012 Clément Bœsch + * + * 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 + */ + +/** + * @file + * SubViewer subtitle demuxer + * @see https://en.wikipedia.org/wiki/SubViewer + */ + +#include "avformat.h" +#include "internal.h" +#include "subtitles.h" +#include "libavcodec/internal.h" +#include "libavutil/avstring.h" +#include "libavutil/bprint.h" +#include "libavutil/intreadwrite.h" + +typedef struct { + FFDemuxSubtitlesQueue q; +} SubViewerContext; + +static int subviewer_probe(AVProbeData *p) +{ + char c; + const unsigned char *ptr = p->buf; + + if (AV_RB24(ptr) == 0xEFBBBF) + ptr += 3; /* skip UTF-8 BOM */ + if (sscanf(ptr, "%*u:%*u:%*u.%*u,%*u:%*u:%*u.%*u%c", &c) == 1) + return AVPROBE_SCORE_EXTENSION; + if (!strncmp(ptr, "[INFORMATION]", 13)) + return AVPROBE_SCORE_MAX/3; + return 0; +} + +static int read_ts(const char *s, int64_t *start, int *duration) +{ + int64_t end; + int hh1, mm1, ss1, ms1; + int hh2, mm2, ss2, ms2; + + if (sscanf(s, "%u:%u:%u.%u,%u:%u:%u.%u", + &hh1, &mm1, &ss1, &ms1, &hh2, &mm2, &ss2, &ms2) == 8) { + end = (hh2*3600LL + mm2*60LL + ss2) * 100LL + ms2; + *start = (hh1*3600LL + mm1*60LL + ss1) * 100LL + ms1; + *duration = end - *start; + return 0; + } + return -1; +} + +static int subviewer_read_header(AVFormatContext *s) +{ + SubViewerContext *subviewer = s->priv_data; + AVStream *st = avformat_new_stream(s, NULL); + AVBPrint header; + int res = 0, new_event = 1; + int64_t pts_start = AV_NOPTS_VALUE; + int duration = -1; + AVPacket *sub = NULL; + + if (!st) + return AVERROR(ENOMEM); + avpriv_set_pts_info(st, 64, 1, 100); + st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE; + st->codec->codec_id = AV_CODEC_ID_SUBVIEWER; + + av_bprint_init(&header, 0, AV_BPRINT_SIZE_UNLIMITED); + + while (!url_feof(s->pb)) { + char line[2048]; + int64_t pos = 0; + int len = ff_get_line(s->pb, line, sizeof(line)); + + if (!len) + break; + + line[strcspn(line, "\r\n")] = 0; + + if (line[0] == '[' && strncmp(line, "[br]", 4)) { + + /* ignore event style, XXX: add to side_data? */ + if (strstr(line, "[COLF]") || strstr(line, "[SIZE]") || + strstr(line, "[FONT]") || strstr(line, "[STYLE]")) + continue; + + if (!st->codec->extradata) { // header not finalized yet + av_bprintf(&header, "%s\n", line); + if (!strncmp(line, "[END INFORMATION]", 17) || !strncmp(line, "[SUBTITLE]", 10)) { + /* end of header */ + res = avpriv_bprint_to_extradata(st->codec, &header); + if (res < 0) + goto end; + } else if (strncmp(line, "[INFORMATION]", 13)) { + /* assume file metadata at this point */ + int i, j = 0; + char key[32], value[128]; + + for (i = 1; i < sizeof(key) - 1 && line[i] && line[i] != ']'; i++) + key[i - 1] = av_tolower(line[i]); + key[i - 1] = 0; + + if (line[i] == ']') + i++; + while (line[i] == ' ') + i++; + while (j < sizeof(value) - 1 && line[i] && line[i] != ']') + value[j++] = line[i++]; + value[j] = 0; + + av_dict_set(&s->metadata, key, value, 0); + } + } + } else if (read_ts(line, &pts_start, &duration) >= 0) { + new_event = 1; + pos = avio_tell(s->pb); + } else if (*line) { + if (!new_event) { + sub = ff_subtitles_queue_insert(&subviewer->q, "\n", 1, 1); + if (!sub) { + res = AVERROR(ENOMEM); + goto end; + } + } + sub = ff_subtitles_queue_insert(&subviewer->q, line, strlen(line), !new_event); + if (!sub) { + res = AVERROR(ENOMEM); + goto end; + } + if (new_event) { + sub->pos = pos; + sub->pts = pts_start; + sub->duration = duration; + } + new_event = 0; + } + } + + ff_subtitles_queue_finalize(&subviewer->q); + +end: + av_bprint_finalize(&header, NULL); + return res; +} + +static int subviewer_read_packet(AVFormatContext *s, AVPacket *pkt) +{ + SubViewerContext *subviewer = s->priv_data; + return ff_subtitles_queue_read_packet(&subviewer->q, pkt); +} + +static int subviewer_read_seek(AVFormatContext *s, int stream_index, + int64_t min_ts, int64_t ts, int64_t max_ts, int flags) +{ + SubViewerContext *subviewer = s->priv_data; + return ff_subtitles_queue_seek(&subviewer->q, s, stream_index, + min_ts, ts, max_ts, flags); +} + +static int subviewer_read_close(AVFormatContext *s) +{ + SubViewerContext *subviewer = s->priv_data; + ff_subtitles_queue_clean(&subviewer->q); + return 0; +} + +AVInputFormat ff_subviewer_demuxer = { + .name = "subviewer", + .long_name = NULL_IF_CONFIG_SMALL("SubViewer subtitle format"), + .priv_data_size = sizeof(SubViewerContext), + .read_probe = subviewer_probe, + .read_header = subviewer_read_header, + .read_packet = subviewer_read_packet, + .read_seek2 = subviewer_read_seek, + .read_close = subviewer_read_close, + .extensions = "sub", +}; |
