Command Line Channel Scanner

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MythTV Command Line Channel Scanner

The backend must not be using the card to be scanned when it is scanned. This generally means that the backend should not be running.

There are four command line parameters to mythtv-setup for channel scanning:

--scan  
Performs a channel scan.
--scan-save-only 
When used with --scan saves the results for later processing instead of importing the results immediately.
--scan-non-interactive 
Answers all the normal questions on import with reasonable answers.
--scan-list  
Lists saved channel scans
--scan-import  
Imports a saved channel scan

The main one is of course --scan, it takes a channel table, a cardid and an input name. The scan table name is of the form standard-modulation-country, for example dvbt-ofdm-uk would scan the channels broadcast over-the-air in the UK. See below for a full table of supported scan tables. The next parameter is the the cardid to scan, the number assigned to each card when you configure a card for use by MythTV. The cardid's available for scanning can be listed by running mythtv-setup --scan with no parameters. The final parameter is the input on the card to scan, with DVB based hardware this will be DVBInput, on all others it is MPEG2TS.

There are two additional arguments you can pass to mythtv-setup when doing a channel scan with --scan. The first "--scan-save-only", will perform the channel scanning step but will not attempt to insert the resulting information into the database for tuning. But instead will save that information for later recall. The other "--scan-non-interactive" will suppress any questions asked by the scanner with regards to inserting channels into the database and will instead assume default answers.

Finally, there are two options that allow you to use the information saved when running a scan with the "--scan-save-only" argument. The "--scan-list" option will simply list all saved scans and the "--scan-import" will insert the saved scan into the database, as if "--scan-save-only" had not been called.

Supported Frequency Tables

Below is a list of frequency tables supported by the command line scanner.

dvbt-ofdm-uk 
Scans Over-The-Air broadcasts in UK
dvbt-ofdm-fi 
Scans Over-The-Air broadcasts in Finland
dvbt-ofdm-se 
Scans Over-The-Air broadcasts in Sweden
dvbt-ofdm-au 
Scans Over-The-Air broadcasts in Australia
dvbt-ofdm-de 
Scans Over-The-Air broadcasts in Germany
dvbt-ofdm-cz 
Scans Over-The-Air broadcasts in the Czech Republic
dvbt-ofdm-gr 
Scans Over-The-Air broadcasts in Greece
dvbt-ofdm-es 
Scans Over-The-Air broadcasts in Spain
dvbt-ofdm-nz 
Scans Over-The-Air broadcasts in New Zealand
dvbt-ofdm-fr 
Scans Over-The-Air broadcasts in France
atsc-vsb8-us 
Scans Over-The-Air broadcasts in US
atsc-qam256-uscable  
Scans the standard US Cable channel frequencies for QAM256 channels
atsc-qam256-uscablehigh 
Scans the standard US Cable channel frequencies for QAM256 channels (only higher frequencies)
atsc-qam256-ushrc  
Scans the alternate HRC US Cable frequencies for QAM256 channels
atsc-qam256-ushrchigh  
Scans the alternate HRC US Cable frequencies for QAM256 channels (only higher frequencies)
atsc-qam256-usirc  
Scans the alternate IRC US Cable frequencies for QAM256 channels
atsc-qam256-usirchigh  
Scans the alternate IRC US Cable frequencies for QAM256 channels (only higher frequencies)

Note: Not explicitly enumerated are the atsc-qam128 and atsc-qam64 tables, these are the same as QAM256 tables. Many cards do not support QAM128 and you are unlikely to ever see it used, but QAM64 is sometimes used in rural areas where the headends are too far from the customers for the higher bitrate QAM256 to be reliable.

Note: HRC and IRC are alternate cable frequency tables used by some operators to avoid interference with Over-The-Air broadcasts.

The high frequency only scans are useful to save time scanning mixed Analog/Digital Systems where you know the lower end is all analog stations or cable modems.