diff options
Diffstat (limited to 'libavformat/microdvddec.c')
| -rw-r--r-- | libavformat/microdvddec.c | 204 |
1 files changed, 204 insertions, 0 deletions
diff --git a/libavformat/microdvddec.c b/libavformat/microdvddec.c new file mode 100644 index 0000000000..a3839051a4 --- /dev/null +++ b/libavformat/microdvddec.c @@ -0,0 +1,204 @@ +/* + * MicroDVD subtitle demuxer + * Copyright (c) 2010 Aurelien Jacobs <aurel@gnuage.org> + * Copyright (c) 2012 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/intreadwrite.h" +#include "libavutil/opt.h" + +#define MAX_LINESIZE 2048 + + +typedef struct { + const AVClass *class; + FFDemuxSubtitlesQueue q; + AVRational frame_rate; +} MicroDVDContext; + + +static int microdvd_probe(AVProbeData *p) +{ + unsigned char c; + const uint8_t *ptr = p->buf; + int i; + + if (AV_RB24(ptr) == 0xEFBBBF) + ptr += 3; /* skip UTF-8 BOM */ + + for (i=0; i<3; i++) { + if (sscanf(ptr, "{%*d}{}%c", &c) != 1 && + sscanf(ptr, "{%*d}{%*d}%c", &c) != 1 && + sscanf(ptr, "{DEFAULT}{}%c", &c) != 1) + return 0; + ptr += ff_subtitles_next_line(ptr); + } + return AVPROBE_SCORE_MAX; +} + +static int64_t get_pts(const char *buf) +{ + int frame; + char c; + + if (sscanf(buf, "{%d}{%c", &frame, &c) == 2) + return frame; + return AV_NOPTS_VALUE; +} + +static int get_duration(const char *buf) +{ + int frame_start, frame_end; + + if (sscanf(buf, "{%d}{%d}", &frame_start, &frame_end) == 2) + return frame_end - frame_start; + return -1; +} + +static const char *bom = "\xEF\xBB\xBF"; + +static int microdvd_read_header(AVFormatContext *s) +{ + AVRational pts_info = (AVRational){ 2997, 125 }; /* default: 23.976 fps */ + MicroDVDContext *microdvd = s->priv_data; + AVStream *st = avformat_new_stream(s, NULL); + int i = 0; + char line_buf[MAX_LINESIZE]; + int has_real_fps = 0; + + if (!st) + return AVERROR(ENOMEM); + + while (!avio_feof(s->pb)) { + char *p; + AVPacket *sub; + int64_t pos = avio_tell(s->pb); + int len = ff_get_line(s->pb, line_buf, sizeof(line_buf)); + char *line = line_buf; + + if (!strncmp(line, bom, 3)) + line += 3; + p = line; + + if (!len) + break; + line[strcspn(line, "\r\n")] = 0; + if (i++ < 3) { + int frame; + double fps; + char c; + + if ((sscanf(line, "{%d}{}%6lf", &frame, &fps) == 2 || + sscanf(line, "{%d}{%*d}%6lf", &frame, &fps) == 2) + && frame <= 1 && fps > 3 && fps < 100) { + pts_info = av_d2q(fps, 100000); + has_real_fps = 1; + continue; + } + if (!st->codec->extradata && sscanf(line, "{DEFAULT}{}%c", &c) == 1) { + st->codec->extradata = av_strdup(line + 11); + if (!st->codec->extradata) + return AVERROR(ENOMEM); + st->codec->extradata_size = strlen(st->codec->extradata) + 1; + continue; + } + } +#define SKIP_FRAME_ID \ + p = strchr(p, '}'); \ + if (!p) { \ + av_log(s, AV_LOG_WARNING, "Invalid event \"%s\"" \ + " at line %d\n", line, i); \ + continue; \ + } \ + p++ + SKIP_FRAME_ID; + SKIP_FRAME_ID; + if (!*p) + continue; + sub = ff_subtitles_queue_insert(µdvd->q, p, strlen(p), 0); + if (!sub) + return AVERROR(ENOMEM); + sub->pos = pos; + sub->pts = get_pts(line); + sub->duration = get_duration(line); + } + ff_subtitles_queue_finalize(µdvd->q); + if (has_real_fps) { + /* export the FPS info only if set in the file */ + microdvd->frame_rate = pts_info; + } else if (microdvd->frame_rate.num) { + /* fallback on user specified frame rate */ + pts_info = microdvd->frame_rate; + } + avpriv_set_pts_info(st, 64, pts_info.den, pts_info.num); + st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE; + st->codec->codec_id = AV_CODEC_ID_MICRODVD; + return 0; +} + +static int microdvd_read_packet(AVFormatContext *s, AVPacket *pkt) +{ + MicroDVDContext *microdvd = s->priv_data; + return ff_subtitles_queue_read_packet(µdvd->q, pkt); +} + +static int microdvd_read_seek(AVFormatContext *s, int stream_index, + int64_t min_ts, int64_t ts, int64_t max_ts, int flags) +{ + MicroDVDContext *microdvd = s->priv_data; + return ff_subtitles_queue_seek(µdvd->q, s, stream_index, + min_ts, ts, max_ts, flags); +} + +static int microdvd_read_close(AVFormatContext *s) +{ + MicroDVDContext *microdvd = s->priv_data; + ff_subtitles_queue_clean(µdvd->q); + return 0; +} + + +#define OFFSET(x) offsetof(MicroDVDContext, x) +#define SD AV_OPT_FLAG_SUBTITLE_PARAM|AV_OPT_FLAG_DECODING_PARAM +static const AVOption microdvd_options[] = { + { "subfps", "set the movie frame rate fallback", OFFSET(frame_rate), AV_OPT_TYPE_RATIONAL, {.dbl=0}, 0, INT_MAX, SD }, + { NULL } +}; + +static const AVClass microdvd_class = { + .class_name = "microdvddec", + .item_name = av_default_item_name, + .option = microdvd_options, + .version = LIBAVUTIL_VERSION_INT, +}; + +AVInputFormat ff_microdvd_demuxer = { + .name = "microdvd", + .long_name = NULL_IF_CONFIG_SMALL("MicroDVD subtitle format"), + .priv_data_size = sizeof(MicroDVDContext), + .read_probe = microdvd_probe, + .read_header = microdvd_read_header, + .read_packet = microdvd_read_packet, + .read_seek2 = microdvd_read_seek, + .read_close = microdvd_read_close, + .priv_class = µdvd_class, +}; |