Frequency scan: Difference between revisions
(→Comparison of DVB frequency scanning commandline utilities: remove the "outdated" and "look dvbv5-scan" comments; there are likely a number of people NOT amused by such commentary) |
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===Digital=== |
===Digital=== |
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On Digital TV, the scanning process consists on tuning into some physical channel/transponder frequencies and parsing the MPEG Transport Stream, in order to identify the services and the corresponding audio, video, teletext and data streams. The service is also known Virtual Channel. |
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One of the handiest tools for scanning frequencies is "[[Scan|(dvb)scan]]", a utility included within the [[LinuxTV dvb-apps]] package. (dvb)scan parses the information from a pre-configured initial scan file that is specific to a particular country/region/location/service_provider (many of which are contained within the dvb-apps package as well as being available within the wiki or elsewhere), then tunes into the frequencies and lists the names for all available PIDs. |
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There are two types of scanning applications: the ones that rely on frequency channel files and the ones that tries hard to identify the existing channels, based on the knowledge of the Country. |
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* [[dvbscan|dvbscan/scandvb/atscscan]] |
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====Scan apps based on a channel file==== |
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* [[w_scan]] |
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Those applications are faster to identify the channels, but they are unable to find any channel outside the channel table. |
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For them to work, an initial file is needed. Those files are provided at [[dtv-scan-tables]] repository, using dvbv5 file format. |
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Most common applications used for channel scan: |
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* [[dvbv5-scan | LinuxTV dvbv5-scan]], part of [[DVBv5_Tools]] package. |
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* [[scan]]/"[[Scan|(dvb)scan]]", part of the unmantained [[LinuxTV dvb-apps]]. |
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* [[scan-s2]] [http://mercurial.intuxication.org/hg/scan-s2/] |
* [[scan-s2]] [http://mercurial.intuxication.org/hg/scan-s2/] |
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* "[[Scan|(dvb)scan]]", a utility included within the [[LinuxTV dvb-apps]] package. |
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* [[dvbv5-scan]] |
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* apps |
* several apps also have their built in scanning ... [[kaffeine]], [[MythTV]], [[Me TV]] |
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====Scan apps that don't require an initial channel file==== |
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Scan applications that don't need a channel file have internally a table that allows them to construct internally a table with possible frequencies and tuning parameters to seek. As the number of possible channels/tuning parameters are a way higher than the ones defined on a channel table, the scanning process will take several minutes (up to an hour, if the card doesn't support autodetection for some DVB properties). |
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Applications using this approach: |
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⚫ | |||
====Comparison of DVB frequency scanning commandline utilities==== |
====Comparison of DVB frequency scanning commandline utilities==== |
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{{Note|The differences between '''scan''' and '''dvbscan''' should be added to this wiki article. The information for dvbscan is still to be completed - please help.}} |
{{Note|The differences between '''scan''' and '''dvbscan''' should be added to this wiki article. The information for dvbscan is still to be completed - please help.}} |
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The following table lists the main features of the |
The following table lists the main features of several of the popularly used command line scanners. For specific information on a particular utility's usage, have a look at its specific wiki article. |
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<br> |
<br> |
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|'''[[dvbv5-scan]]''' |
|'''[[dvbv5-scan]]''' |
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|- |
|- |
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|'''download''' |
|'''download (upstream version)''' |
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|[http://linuxtv.org/hg/dvb-apps linuxtv.org/hg/dvb-apps] |
|[http://linuxtv.org/hg/dvb-apps linuxtv.org/hg/dvb-apps] |
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|[http://linuxtv.org/hg/dvb-apps linuxtv.org/hg/dvb-apps] |
|[http://linuxtv.org/hg/dvb-apps linuxtv.org/hg/dvb-apps] |
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|[http://wirbel.htpc-forum.de/w_scan/index.html wirbel.htpc-forum.de/w_scan/index.html] |
|[http://wirbel.htpc-forum.de/w_scan/index.html wirbel.htpc-forum.de/w_scan/index.html] |
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|[http://mercurial.intuxication.org/hg/scan-s2 mercurial.intuxication.org/hg/scan-s2] |
|[http://mercurial.intuxication.org/hg/scan-s2 mercurial.intuxication.org/hg/scan-s2] |
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|[http://git.linuxtv.org/v4l-utils.git |
|[http://git.linuxtv.org/v4l-utils.git git.linuxtv.org/v4l-utils.git] |
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|- |
|- |
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|'''last stable''' |
|'''last stable''' |
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|none / use latest version |
|none / use latest version |
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| ? |
| ? |
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|v4l-utils-1.4.0 |
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|none / use latest version |
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|- |
|- |
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|'''comments''' |
|'''comments''' |
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|linuxtv.org |
|linuxtv.org unmaintained<br>'''DVB-S2 and DVB-T2 support missing''' |
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|linuxtv.org unmaintained<br>'''DVB-S2 and DVB-T2 support missing''' |
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⚫ | |||
⚫ | |||
|linuxtv.org maintained |
|linuxtv.org maintained |
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⚫ | |||
|compiling needs dvb driver with API-5.0 or higher<br>usage needs API-3.2 or API-5.x |
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|'''DVB API needs''' |
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⚫ | |||
|DVB API version 3.2 or higher |
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|needs dvb driver with 5.5 or higher<br>in development (01/2012)<br>file format (up to now) incompatible to other apps |
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|DVB API version 3.2 or higher |
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|DVB API version 3.2 or higher<br>compiling needs DVB API version 5.0 or higher |
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⚫ | |||
|DVB API version 3.2 or higher |
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|- |
|- |
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|'''supported DTV types''' |
|'''supported DTV types''' |
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|DVB-S, DVB-C(Europe), DVB-T, ATSC (VSB and QAM |
|DVB-S, DVB-C (Annex A only - mainly Europe), DVB-T, ATSC (VSB and QAM) |
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|DVB-S, DVB-C (Annex A only - mainly Europe), DVB-T, ATSC (VSB and QAM) |
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| ? |
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|DVB-S, '''DVB-S2''', DVB-C(Europe), DVB-T/T2, ATSC (VSB and QAM), DMB-TH (China) |
|DVB-S, '''DVB-S2''', DVB-C (Annex A only - mainly Europe), DVB-T, '''DVB/T2''', ATSC (VSB and QAM), DMB-TH (China) |
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|DVB-S, '''DVB-S2''', DVB-C(Europe), DVB-T, ATSC (VSB and QAM) |
|DVB-S, '''DVB-S2''', DVB-C (Annex A only - mainly Europe), DVB-T, ATSC (VSB and QAM) |
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| |
|DVB-S, '''DVB-S2''', DVB-C (Annex A and C - worldwide), DVB-T, '''DVB-T2''', ATSC (VSB and QAM), ISDB-T and more |
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|- |
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|'''initial scan file required'''<br>(matching to your satellite or local aerial/cable network) |
|'''initial scan file required'''<br>(matching to your satellite or local aerial/cable network) |
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|yes (use dvb-apps hg from linuxtv.org) |
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|yes |
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|yes (use dvb-apps hg from linuxtv.org) |
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|'''not required''' |
|'''not required''' |
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|yes |
|yes<br>''NOTE: slightly different file format from scan because of additional DVB-S2 support.'' |
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|yes (uses libdvbv5 file format by default, but dvb-apps and s2-scan file formats are accepted too) |
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|yes (new file format) |
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|'''can generate initial scan file''' |
|'''can generate initial scan file''' |
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|'''can generate channels.conf for zap/xine/mplayer/vlc''' |
|'''can generate channels.conf for zap/xine/mplayer/vlc''' |
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|yes (default) |
|yes (default) |
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|yes (default) |
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⚫ | |||
|yes |
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|yes |
|yes |
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|yes |
|yes |
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|yes (but new file format is default) |
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|'''can generate channels.conf for [http://www.tvdr.de/ VDR]''' |
|'''can generate channels.conf for [http://www.tvdr.de/ VDR]''' |
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|yes, but hopeless outdated (vdr-1.3 only) |
|yes, but hopeless outdated (vdr-1.3 only) |
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|yes, but hopeless outdated (vdr-1.3 only) |
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|yes (default) |
|yes (default) |
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|yes (default) |
|yes (default) |
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|yes (after version 1.4.0) |
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|- |
|- |
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|'''can generate channels.dvb for kaffeine''' |
|'''can generate channels.dvb for kaffeine''' |
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|no |
|no |
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⚫ | |||
⚫ | |||
|no |
|no |
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|'''yes''' |
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|no (new file format) |
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|no |
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|no |
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|} |
|} |
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Revision as of 16:29, 22 November 2014
In order to be able receive a particular signal with your TV tuner device you will need to tune/set it to the correct radio frequency used by that source transmission. Therefore, you (or, at least, the viewing application you are using) will first want to know which frequencies are used for transmission and, thereby, may be tunable by your receiver at your residing location. Frequency scanning utilities, listed below, perform such signal detection and, generally, provide a list of the frequencies upon which content is discovered, with which higher level applications can then in turn use for tuning purposes.
Note: Historically, the set of frequencies used under the older analogue systems have differed from one another, meaning that the particular frequencies used across North America, Europe, Asia, etc., etc., will differ depending upon the transmission standard adopted within each nation. When countries began to make the transition to digital TV systems, most have opted to continue to use their old channel frequency schemes so as to make the switch from analog to digital systems as seamless as possible for the end user.
Frequency Scanning Utilities
Analog
- scantv (part of xawtv package, both branches)
- apps with built in scanning ... tvtime, xawtv/motv (which call upon scantv), kdetv ...
Digital
On Digital TV, the scanning process consists on tuning into some physical channel/transponder frequencies and parsing the MPEG Transport Stream, in order to identify the services and the corresponding audio, video, teletext and data streams. The service is also known Virtual Channel.
There are two types of scanning applications: the ones that rely on frequency channel files and the ones that tries hard to identify the existing channels, based on the knowledge of the Country.
Scan apps based on a channel file
Those applications are faster to identify the channels, but they are unable to find any channel outside the channel table.
For them to work, an initial file is needed. Those files are provided at dtv-scan-tables repository, using dvbv5 file format.
Most common applications used for channel scan:
- LinuxTV dvbv5-scan, part of DVBv5_Tools package.
- alexplore (part of the v4 xawtv package).
- scan/"(dvb)scan", part of the unmantained LinuxTV dvb-apps.
- scan-s2 [1]
- "(dvb)scan", a utility included within the LinuxTV dvb-apps package.
- several apps also have their built in scanning ... kaffeine, MythTV, Me TV
Scan apps that don't require an initial channel file
Scan applications that don't need a channel file have internally a table that allows them to construct internally a table with possible frequencies and tuning parameters to seek. As the number of possible channels/tuning parameters are a way higher than the ones defined on a channel table, the scanning process will take several minutes (up to an hour, if the card doesn't support autodetection for some DVB properties).
Applications using this approach:
Comparison of DVB frequency scanning commandline utilities
The following table lists the main features of several of the popularly used command line scanners. For specific information on a particular utility's usage, have a look at its specific wiki article.
feature \ scanner | scan | dvbscan | w_scan | scan-s2 | dvbv5-scan |
download (upstream version) | linuxtv.org/hg/dvb-apps | linuxtv.org/hg/dvb-apps | wirbel.htpc-forum.de/w_scan/index.html | mercurial.intuxication.org/hg/scan-s2 | git.linuxtv.org/v4l-utils.git |
last stable | linuxtv-dvb-apps-1.1.1 | linuxtv-dvb-apps-1.1.1 | none / use latest version | ? | v4l-utils-1.4.0 |
comments | linuxtv.org unmaintained DVB-S2 and DVB-T2 support missing |
linuxtv.org unmaintained DVB-S2 and DVB-T2 support missing |
linuxtv.org maintained | ||
DVB API needs | DVB API version 3.2 or higher | DVB API version 3.2 or higher | DVB API version 3.2 or higher compiling needs DVB API version 5.0 or higher |
DVB API version 5.0 or higher last update 02/2009 |
DVB API version 3.2 or higher |
supported DTV types | DVB-S, DVB-C (Annex A only - mainly Europe), DVB-T, ATSC (VSB and QAM) | DVB-S, DVB-C (Annex A only - mainly Europe), DVB-T, ATSC (VSB and QAM) | DVB-S, DVB-S2, DVB-C (Annex A only - mainly Europe), DVB-T, DVB/T2, ATSC (VSB and QAM), DMB-TH (China) | DVB-S, DVB-S2, DVB-C (Annex A only - mainly Europe), DVB-T, ATSC (VSB and QAM) | DVB-S, DVB-S2, DVB-C (Annex A and C - worldwide), DVB-T, DVB-T2, ATSC (VSB and QAM), ISDB-T and more |
initial scan file required (matching to your satellite or local aerial/cable network) |
yes | yes | not required | yes NOTE: slightly different file format from scan because of additional DVB-S2 support. |
yes (uses libdvbv5 file format by default, but dvb-apps and s2-scan file formats are accepted too) |
can generate initial scan file | no | no | yes | no | no |
can generate channels.conf for zap/xine/mplayer/vlc | yes (default) | yes (default) | yes | yes | yes |
can generate channels.conf for VDR | yes, but hopeless outdated (vdr-1.3 only) | yes, but hopeless outdated (vdr-1.3 only) | yes (default) | yes (default) | yes (after version 1.4.0) |
can generate channels.dvb for kaffeine | no | no | yes | no | no |
External Links
Analog
Digital For some other general sources (which may or may not be that useful) for finding local channel frequency lists, see: