[FFmpeg-cvslog] avformat/dvbtxt: add raw demuxer for dvb teletext probing
Marton Balint
git at videolan.org
Fri Feb 19 23:09:41 CET 2016
ffmpeg | branch: master | Marton Balint <cus at passwd.hu> | Tue Feb 16 03:05:10 2016 +0100| [51afd9f4e1f79144d0ff2874c55f55eaba012343] | committer: Marton Balint
avformat/dvbtxt: add raw demuxer for dvb teletext probing
Signed-off-by: Marton Balint <cus at passwd.hu>
> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=51afd9f4e1f79144d0ff2874c55f55eaba012343
---
libavcodec/dvbtxt.h | 41 +++++++++++++++++++++++++++++++++++++
libavformat/Makefile | 1 +
libavformat/allformats.c | 1 +
libavformat/dvbtxt.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++
libavformat/utils.c | 1 +
libavformat/version.h | 4 ++--
6 files changed, 96 insertions(+), 2 deletions(-)
diff --git a/libavcodec/dvbtxt.h b/libavcodec/dvbtxt.h
new file mode 100644
index 0000000..ff88fcf
--- /dev/null
+++ b/libavcodec/dvbtxt.h
@@ -0,0 +1,41 @@
+/*
+ * DVB teletext common functions.
+ *
+ * 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
+ */
+
+#ifndef AVCODEC_DVBTXT_H
+#define AVCODEC_DVBTXT_H
+
+#include "libavutil/attributes.h"
+
+/* Returns true if data identifier matches a teletext stream according to EN
+ * 301 775 section 4.4.2 */
+static av_always_inline int ff_data_identifier_is_teletext(int data_identifier)
+{
+ return (data_identifier >= 0x10 && data_identifier <= 0x1F ||
+ data_identifier >= 0x99 && data_identifier <= 0x9B);
+}
+
+/* Returns true if data unit id matches EBU teletext data according to
+ * EN 301 775 section 4.4.2 */
+static av_always_inline int ff_data_unit_id_is_teletext(int data_unit_id)
+{
+ return (data_unit_id == 0x02 || data_unit_id == 0x03);
+}
+
+#endif /* AVCODEC_DVBTXT_H */
diff --git a/libavformat/Makefile b/libavformat/Makefile
index 001b3f1..aace6f7 100644
--- a/libavformat/Makefile
+++ b/libavformat/Makefile
@@ -144,6 +144,7 @@ OBJS-$(CONFIG_DTS_MUXER) += rawenc.o
OBJS-$(CONFIG_DV_DEMUXER) += dv.o
OBJS-$(CONFIG_DV_MUXER) += dvenc.o
OBJS-$(CONFIG_DVBSUB_DEMUXER) += dvbsub.o
+OBJS-$(CONFIG_DVBTXT_DEMUXER) += dvbtxt.o
OBJS-$(CONFIG_DXA_DEMUXER) += dxa.o
OBJS-$(CONFIG_EA_CDATA_DEMUXER) += eacdata.o
OBJS-$(CONFIG_EA_DEMUXER) += electronicarts.o
diff --git a/libavformat/allformats.c b/libavformat/allformats.c
index 02bb16a..9662941 100644
--- a/libavformat/allformats.c
+++ b/libavformat/allformats.c
@@ -121,6 +121,7 @@ void av_register_all(void)
REGISTER_DEMUXER (DTSHD, dtshd);
REGISTER_MUXDEMUX(DV, dv);
REGISTER_DEMUXER (DVBSUB, dvbsub);
+ REGISTER_DEMUXER (DVBTXT, dvbtxt);
REGISTER_DEMUXER (DXA, dxa);
REGISTER_DEMUXER (EA, ea);
REGISTER_DEMUXER (EA_CDATA, ea_cdata);
diff --git a/libavformat/dvbtxt.c b/libavformat/dvbtxt.c
new file mode 100644
index 0000000..6828738
--- /dev/null
+++ b/libavformat/dvbtxt.c
@@ -0,0 +1,50 @@
+/*
+ * RAW dvb teletext demuxer
+ * Copyright (c) 2016 Marton Balnt <cus at passwd.hu>
+ *
+ * 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 "libavcodec/dvbtxt.h"
+
+#include "avformat.h"
+#include "rawdec.h"
+
+static int dvbtxt_probe(AVProbeData *p)
+{
+ const uint8_t *end = p->buf + p->buf_size;
+ const uint8_t *buf;
+
+ /* The purpose of this is demuxer is to detect DVB teletext streams in
+ * mpegts, so we reject invalid buffer sizes */
+ if ((p->buf_size + 45) % 184 != 0)
+ return 0;
+
+ if (!ff_data_identifier_is_teletext(p->buf[0]))
+ return 0;
+
+ for (buf = p->buf + 1; buf < end; buf += 46) {
+ if (!ff_data_unit_id_is_teletext(buf[0]) && buf[0] != 0xff)
+ return 0;
+ if (buf[1] != 0x2c) // data_unit_length
+ return 0;
+ }
+
+ return AVPROBE_SCORE_MAX / 2;
+}
+
+FF_DEF_RAWSUB_DEMUXER(dvbtxt, "dvbtxt", dvbtxt_probe, NULL, AV_CODEC_ID_DVB_TELETEXT, 0)
diff --git a/libavformat/utils.c b/libavformat/utils.c
index 129a49d..671a0c2 100644
--- a/libavformat/utils.c
+++ b/libavformat/utils.c
@@ -285,6 +285,7 @@ static int set_codec_from_probe_data(AVFormatContext *s, AVStream *st,
{ "ac3", AV_CODEC_ID_AC3, AVMEDIA_TYPE_AUDIO },
{ "dts", AV_CODEC_ID_DTS, AVMEDIA_TYPE_AUDIO },
{ "dvbsub", AV_CODEC_ID_DVB_SUBTITLE,AVMEDIA_TYPE_SUBTITLE },
+ { "dvbtxt", AV_CODEC_ID_DVB_TELETEXT,AVMEDIA_TYPE_SUBTITLE },
{ "eac3", AV_CODEC_ID_EAC3, AVMEDIA_TYPE_AUDIO },
{ "h264", AV_CODEC_ID_H264, AVMEDIA_TYPE_VIDEO },
{ "hevc", AV_CODEC_ID_HEVC, AVMEDIA_TYPE_VIDEO },
diff --git a/libavformat/version.h b/libavformat/version.h
index a696474..82a8892 100644
--- a/libavformat/version.h
+++ b/libavformat/version.h
@@ -30,8 +30,8 @@
#include "libavutil/version.h"
#define LIBAVFORMAT_VERSION_MAJOR 57
-#define LIBAVFORMAT_VERSION_MINOR 25
-#define LIBAVFORMAT_VERSION_MICRO 102
+#define LIBAVFORMAT_VERSION_MINOR 26
+#define LIBAVFORMAT_VERSION_MICRO 100
#define LIBAVFORMAT_VERSION_INT AV_VERSION_INT(LIBAVFORMAT_VERSION_MAJOR, \
LIBAVFORMAT_VERSION_MINOR, \
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