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-rw-r--r--libavformat/supdec.c109
1 files changed, 109 insertions, 0 deletions
diff --git a/libavformat/supdec.c b/libavformat/supdec.c
new file mode 100644
index 0000000000..48083b2c53
--- /dev/null
+++ b/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,
+};