diff options
Diffstat (limited to 'libavformat/microdvddec.c')
| -rw-r--r-- | libavformat/microdvddec.c | 129 |
1 files changed, 129 insertions, 0 deletions
diff --git a/libavformat/microdvddec.c b/libavformat/microdvddec.c new file mode 100644 index 0000000..95c76af --- /dev/null +++ b/libavformat/microdvddec.c @@ -0,0 +1,129 @@ +/* + * MicroDVD subtitle demuxer + * Copyright (c) 2010 Aurelien Jacobs <aurel@gnuage.org> + * + * 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 "libavutil/intreadwrite.h" + +#define MAX_LINESIZE 2048 + + +typedef struct { + uint8_t lines[3][MAX_LINESIZE]; + int64_t pos[3]; +} MicroDVDContext; + + +static int microdvd_probe(AVProbeData *p) +{ + unsigned char c, *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 += strcspn(ptr, "\n") + 1; + } + return AVPROBE_SCORE_MAX; +} + +static int microdvd_read_header(AVFormatContext *s, AVFormatParameters *ap) +{ + AVRational pts_info = (AVRational){ 2997, 125 }; /* default: 23.976 fps */ + MicroDVDContext *microdvd = s->priv_data; + AVStream *st = av_new_stream(s, 0); + int i, frame; + double fps; + char c; + + if (!st) + return -1; + for (i=0; i<FF_ARRAY_ELEMS(microdvd->lines); i++) { + microdvd->pos[i] = avio_tell(s->pb); + ff_get_line(s->pb, microdvd->lines[i], sizeof(microdvd->lines[i])); + if ((sscanf(microdvd->lines[i], "{%d}{}%6lf", &frame, &fps) == 2 || + sscanf(microdvd->lines[i], "{%d}{%*d}%6lf", &frame, &fps) == 2) + && frame <= 1 && fps > 3 && fps < 100) + pts_info = av_d2q(fps, 100000); + if (sscanf(microdvd->lines[i], "{DEFAULT}{}%c", &c) == 1) { + st->codec->extradata = av_strdup(microdvd->lines[i] + 11); + st->codec->extradata_size = strlen(st->codec->extradata); + i--; + } + } + av_set_pts_info(st, 64, pts_info.den, pts_info.num); + st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE; + st->codec->codec_id = CODEC_ID_MICRODVD; + return 0; +} + +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 microdvd_read_packet(AVFormatContext *s, AVPacket *pkt) +{ + MicroDVDContext *microdvd = s->priv_data; + char buffer[MAX_LINESIZE]; + int64_t pos = avio_tell(s->pb); + int i, len = 0, res = AVERROR_EOF; + + for (i=0; i<FF_ARRAY_ELEMS(microdvd->lines); i++) { + if (microdvd->lines[i][0]) { + strcpy(buffer, microdvd->lines[i]); + pos = microdvd->pos[i]; + len = strlen(buffer); + microdvd->lines[i][0] = 0; + break; + } + } + if (!len) + len = ff_get_line(s->pb, buffer, sizeof(buffer)); + + if (buffer[0] && !(res = av_new_packet(pkt, len))) { + memcpy(pkt->data, buffer, len); + pkt->flags |= AV_PKT_FLAG_KEY; + pkt->pos = pos; + pkt->pts = pkt->dts = get_pts(buffer); + } + return res; +} + +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, + .flags = AVFMT_GENERIC_INDEX, +}; |
