--- /dev/null
+DVB TOOLS
+=========
+
+This is a series of tools written to help testing and working with DVB,
+using its latest V5 API. The tools can also work with the DVBv3 API.
+
+The current tools are:
+
+dvb-fe-tool - a simple test application, that reads from the frontend.
+ it also allows to change the default delivery system.
+ In the future, it may be used to change any property
+ via command line.
+
+dvb-format-convert - converts from zap and scan "initial-tuning-data-file"
+ into the new format defined to work with DVBv5;
+
+dvbv5-scan - a DVBv5 scan tool;
+
+dvbv5-zap - a DVBv5 zap tool. It allow to tune into a DVB channel, and
+ to watch to a DVB service (e. g. receiving the video and audio
+ streams, via another application using the dvr device).
+
+Each application code is very small, as most of the code are on some
+generic code that will become a library in the future.
+
+CONTENTS OF THE TREE
+====================
+
+parse_string.c/parse_string.h: MPEG-TS string decoder with charset translator
+
+Used to decode NIT/SDT service name, network provider and provider name.
+It parses the charsets according with the DVB specs, converting them into
+UTF-8 (or other charset), using iconv library.
+
+descriptors.c/descriptors.h: MPEG-TS descriptors parser
+
+The code there is generig enough to decode the MPEG-TS descriptors,
+with the DVB and other Digital TV extensions.
+
+libscan.c/libscan/h: DVBv5 scanning library
+
+This library is used to retrieve DVB information from the MPEG TS
+headers, discovering the services associated to each DVB channel or
+transponder. The services information is the basic info that most
+DVB tools need to tune into a channel.
+
+dvb-file.c/dvb-file.h: DVB file read/write library.
+
+Allows parsing a DVB file (legacy or not) and to write data into a
+DVB file (new format only).
+
+dvb-fe.c/dvb-fe.h: DVB frontend library.
+
+Allows talking with a DVB frontend via DVBv5 or DVBv3 API.
+
+dvb-zap-format.c/dvb-legacy-channel-format.c:
+
+Contains the data structures required in order to read from the legacy
+formats (zap or scan "initial-tuning-data-file").
+
+dvb_frontend.h: DVBv5 frontend API.
+
+This is just a copy of the newest linux/dvb/frontend.h header.
+I opted to keep a copy there, in order to allow working with the tools
+without needing to copy the latest header into /usr/include.
+
+dvb-v5.h/dvb-v5-std.h:
+
+Ancillary files linked into dvb-fe code, used to parse DVB tables. The
+dvbv5.h is generated by a small perl util, from the DVB FE API file.
+
+dvb-demux.c/dvb-demux.h: DVB demux library.
+
+Used by the dvbv5-zap utility.
+
+dvb-fe-tool.c, dvb-format-convert.c, dvbv5-zap.c, dvbv5-scan.c: tools code.
+
+Basically, parses the options from userspace and calls the other code
+to do what was requested by the user.
+
+CHANNEL/SERVICE FILE FORMAT
+===========================
+
+Instead of having two different files, one for services, and another for
+channels/transponders, I opted to use just one format for both. The
+format is:
+
+[channel]
+key1=value1
+key2=value2
+key3=value3
+...
+keyn=valuen
+
+
+lines with # are discarted by the parsers. Also, whitespaces/tabs before
+the keys and before/after the equal sign.
+
+Be careful: whitespace in the middle of the value are not discarded.
+
+A typical service would be like:
+
+[TV Brasil HD]
+ VCHANNEL = 2.2
+ SERVICE_ID = 16160
+ VIDEO_PID = 770
+ AUDIO_PID = 514 614
+ FREQUENCY = 479142857
+ MODULATION = QAM/AUTO
+ BANDWIDTH_HZ = 6000000
+ INVERSION = AUTO
+ CODE_RATE_HP = AUTO
+ CODE_RATE_LP = NONE
+ GUARD_INTERVAL = AUTO
+ TRANSMISSION_MODE = AUTO
+ HIERARCHY = NONE
+ ISDBT_LAYER_ENABLED = 7
+ ISDBT_PARTIAL_RECEPTION = 0
+ ISDBT_SOUND_BROADCASTING = 0
+ ISDBT_SB_SUBCHANNEL_ID = 0
+ ISDBT_SB_SEGMENT_IDX = 0
+ ISDBT_SB_SEGMENT_COUNT = 0
+ ISDBT_LAYERA_FEC = AUTO
+ ISDBT_LAYERA_MODULATION = QAM/AUTO
+ ISDBT_LAYERA_SEGMENT_COUNT = 0
+ ISDBT_LAYERA_TIME_INTERLEAVING = 0
+ ISDBT_LAYERB_FEC = AUTO
+ ISDBT_LAYERB_MODULATION = QAM/AUTO
+ ISDBT_LAYERB_SEGMENT_COUNT = 0
+ ISDBT_LAYERB_TIME_INTERLEAVING = 0
+ ISDBT_LAYERC_FEC = AUTO
+ ISDBT_LAYERC_MODULATION = QAM/AUTO
+ ISDBT_LAYERC_SEGMENT_COUNT = 0
+ ISDBT_LAYERC_TIME_INTERLEAVING = 0
+ DELIVERY_SYSTEM = ISDBT
+
+Just the channel description for it would be:
+
+[CHANNEL]
+ FREQUENCY = 479142857
+ MODULATION = QAM/AUTO
+ BANDWIDTH_HZ = 6000000
+ INVERSION = AUTO
+ CODE_RATE_HP = AUTO
+ CODE_RATE_LP = NONE
+ GUARD_INTERVAL = AUTO
+ TRANSMISSION_MODE = AUTO
+ HIERARCHY = NONE
+ ISDBT_LAYER_ENABLED = 7
+ ISDBT_PARTIAL_RECEPTION = 0
+ ISDBT_SOUND_BROADCASTING = 0
+ ISDBT_SB_SUBCHANNEL_ID = 0
+ ISDBT_SB_SEGMENT_IDX = 0
+ ISDBT_SB_SEGMENT_COUNT = 0
+ ISDBT_LAYERA_FEC = AUTO
+ ISDBT_LAYERA_MODULATION = QAM/AUTO
+ ISDBT_LAYERA_SEGMENT_COUNT = 0
+ ISDBT_LAYERA_TIME_INTERLEAVING = 0
+ ISDBT_LAYERB_FEC = AUTO
+ ISDBT_LAYERB_MODULATION = QAM/AUTO
+ ISDBT_LAYERB_SEGMENT_COUNT = 0
+ ISDBT_LAYERB_TIME_INTERLEAVING = 0
+ ISDBT_LAYERC_FEC = AUTO
+ ISDBT_LAYERC_MODULATION = QAM/AUTO
+ ISDBT_LAYERC_SEGMENT_COUNT = 0
+ ISDBT_LAYERC_TIME_INTERLEAVING = 0
+ DELIVERY_SYSTEM = ISDBT
+
+CURRENT ISSUES
+==============
+
+The dvb-fe-tool and the dvb-format-convert are generic enough to work
+with all delivery systems. However, the other two tools need to do
+some diferent things, depending on the delivery system.
+
+I'm currently with only ISDB-T signals here, so the other two
+tools were tested only with it.
+
+The dvbv5-zap in general won't work with Satellite delivery
+systems. It lacks polarity settings, and it doesn't know anything
+about LNB or DISEqC. It shouldn't hard to port those things into it,
+but a DVB-S signal is needed to test. As I don't have it curently,
+I'm not working to add support for it at the moment.
+
+Patches are welcome.
+
+The dvbv5-scan also won't work with Satellite delivery systems
+due to the same reasons.
+
+Patches are welcome.
+
+The dvbv5-scan should likely work with the other standards, but the
+descriptor parser for NIT, PAT, PMT and SDT tables are fine-tuned
+for ISDB-T. Adding more parsed info there could help to improve the
+detected things, like virtual channels. Maybe some additional
+tables would need to be parsed for ATSC.
+
+It also doesn't current look inside the network descriptors to get
+other transponders. So, on DVB-C, it will only get the channels
+at the main frequency. I should fix it in a near future.
+
+It is very likely that it will work as-is for DVB-T.
+
+If someone wants to patch the code to improve the tool, the descriptors
+parser is inside descriptors.c file. The scan code that uses it is
+at libscan.c. Finally, the data structure used by the scan parsing
+is at libscan.h. The procedure is basicallt to add a new data field inside
+the libscan.h structures, and then change the descriptors.c file
+to fill it.
+
+The main structure is this one:
+
+struct dvb_descriptors {
+ int verbose;
+
+ struct pat_table pat_table;
+ struct nit_table nit_table;
+ struct sdt_table sdt_table;
+
+ /* Used by descriptors to know where to update a PMT/Service/TS */
+ unsigned cur_pmt;
+ unsigned cur_service;
+ unsigned cur_ts;
+};
+
+While parsing each table, the current item being parsed is pointed by
+one of those unsigned values: cur_pmt, cur_service, cur_ts. Use this
+to fill the data structure.
+
+The dvb-file will likely need changes too, in order to write the
+parsed information inside the channels file.
+
+Patches are welcome!
+
+Regards,
+Mauro Carvalho Chehab
+2012-January-7
projects / platform / upstream / v4l-utils.git / commitdiff