"w_scan" is a small command line utility for scanning DVB and ATSC. It may create directly channels.conf files as well as creating initial tuning data for scan which is contained in the LinuxTV dvb-apps.
w_scan doesn't have a man page. However, if you run it with the -h parameter, the output provides a summary of its command line options.
w_scan [options...] >> channels.conf
If you try to use w_scan you should at least specify two parameters: frontend type and output format.
If not specified w_scan defaults to do a scan for European terrestrial DVB-T with output format VDR channels.conf.
ATSC Type (ignored for DVB-C and DVB-T)
"initial tuning data" for Scan
channels.dvb for Kaffeine
Experts or experienced users may use some of the other options, but this is not recommended.
NOTE: ATSC support needs w_scan >= 20080815
Scanning ATSC VSB (North America, Over-the-Air)
$ w_scan -fa -A1 -X
Scanning ATSC QAM annex B (North America, digital cable TV)
$ w_scan -fa -A2 -X
Scanning DVB-T (Europe, Over-the-Air)
$ w_scan -ft -X
Scanning DVB-C (Europe, digital cable TV)
$ w_scan -fc -X
Generating dvbscan tuning data
Exactly as above, just specify output format dvbscan with "-x":
$ w_scan -f <FRONTEND_TYPE> -x >cc-Ttttt
If you choose to create an initial scan file (and you know the name of your local transmitter or cable provider), you can send the resulting file to the dvb mailing list after checking that it hasn't already been posted or added to the scan directory in the dvb-apps repository.