X-Git-Url: https://git.piment-noir.org/?p=deb_ffmpeg.git;a=blobdiff_plain;f=ffmpeg%2Flibavformat%2Fsupdec.c;fp=ffmpeg%2Flibavformat%2Fsupdec.c;h=48083b2c537020bf37add14f5e1f02349fe4640b;hp=0000000000000000000000000000000000000000;hb=f6fa7814ccfe3e76514b36cf04f5cd3cb657c8cf;hpb=2ba45a602cbfa7b771effba9b11bb4245c21bc00 diff --git a/ffmpeg/libavformat/supdec.c b/ffmpeg/libavformat/supdec.c new file mode 100644 index 0000000..48083b2 --- /dev/null +++ b/ffmpeg/libavformat/supdec.c @@ -0,0 +1,109 @@ +/* + * 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 SUP_PGS_MAGIC 0x5047 /* "PG", big endian */ + +static int sup_read_header(AVFormatContext *s) +{ + AVStream *st = avformat_new_stream(s, NULL); + if (!st) + return AVERROR(ENOMEM); + st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE; + st->codec->codec_id = AV_CODEC_ID_HDMV_PGS_SUBTITLE; + avpriv_set_pts_info(st, 32, 1, 90000); + + return 0; +} + +static int sup_read_packet(AVFormatContext *s, AVPacket *pkt) +{ + int64_t pts, dts, pos; + int ret; + + pos = avio_tell(s->pb); + + if (avio_rb16(s->pb) != SUP_PGS_MAGIC) + return avio_feof(s->pb) ? AVERROR_EOF : AVERROR_INVALIDDATA; + + pts = avio_rb32(s->pb); + dts = avio_rb32(s->pb); + + if ((ret = av_get_packet(s->pb, pkt, 3)) < 0) + return ret; + + pkt->stream_index = 0; + pkt->flags |= AV_PKT_FLAG_KEY; + pkt->pos = pos; + pkt->pts = pts; + // Many files have DTS set to 0 for all packets, so assume 0 means unset. + pkt->dts = dts ? dts : AV_NOPTS_VALUE; + + if (pkt->size >= 3) { + // The full packet size is stored as part of the packet. + size_t len = AV_RB16(pkt->data + 1); + + if ((ret = av_append_packet(s->pb, pkt, len)) < 0) + return ret; + } + + return 0; +} + +static int sup_probe(AVProbeData *p) +{ + unsigned char *buf = p->buf; + size_t buf_size = p->buf_size; + int nb_packets; + + for (nb_packets = 0; nb_packets < 10; nb_packets++) { + size_t full_packet_size; + if (buf_size < 10 + 3) + break; + if (AV_RB16(buf) != SUP_PGS_MAGIC) + return 0; + full_packet_size = AV_RB16(buf + 10 + 1) + 10 + 3; + if (buf_size < full_packet_size) + break; + buf += full_packet_size; + buf_size -= full_packet_size; + } + if (!nb_packets) + return 0; + if (nb_packets < 2) + return AVPROBE_SCORE_RETRY / 2; + if (nb_packets < 4) + return AVPROBE_SCORE_RETRY; + if (nb_packets < 10) + return AVPROBE_SCORE_EXTENSION; + return AVPROBE_SCORE_MAX; +} + +AVInputFormat ff_sup_demuxer = { + .name = "sup", + .long_name = NULL_IF_CONFIG_SMALL("raw HDMV Presentation Graphic Stream subtitles"), + .extensions = "sup", + .mime_type = "application/x-pgs", + .read_probe = sup_probe, + .read_header = sup_read_header, + .read_packet = sup_read_packet, + .flags = AVFMT_GENERIC_INDEX, +};