w scan

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w_scan is a small command line utility used to perform frequency scans for DVB and ATSC transmissions. It is not included in LinuxTV dvb-apps, but complements the two frequency scanning utilities available through LinuxTV dvb-apps, dvbscan and scan.

w_scan is capable of directly creating channels.conf files as well as initial tuning data for scan.

Obtaining w_scan

w_scan can be obtained here.


Detailed information can be found in the w_scan man page (i.e. from a console, run man w_scan). Additionally, running w_scan with the -h parameter will produce an output that provides a summary of it's main command line options.

w_scan [options...] >> channels.conf

In general, when using w_scan you should at least specify three parameters: frontend type, country/satellite and output format. The following table summarizes the basic command line essentials for using w_scan.

Basic w_scan commandline parameters and their respective options
Parameter Argument Description & Options
Frontend Type -fType

a = ATSC (North America, cable and terrestrial)
c = DVB-C (Europe, cable)
s = DVB-S/S2 (Satellite)
t = DVB-T/T2 (Europe, terrestrial = default)


  • ATSC support requires a w_scan version >= 20080815
  • Satellite support requires a w_scan version >= 20090504)
ATSC Type -AType

(ignored for DVB-C and DVB-T)
1 = VSB ("Over-the-Air)"
2 = QAM annex B ("cable TV")
3 = both of them

Country ID -cID

(mandatory for ATSC, DVB-C, DVB-T/T2)
uppercase two character identifier as defined in ISO 3166-1,
see -c? for list of countries.

Satellite ID -sID

(mandatory for DVB-S/S2)
uppercase character constant with E (east) or W (west) as separator,
see -s? for list of satellites.

Output Format -Format

X = czap/tzap/xine channels.conf
x = "initial tuning data" for Scan
G = Gstreamer dvbsrc Plugin
L = VLC xspf playlist (experimental)
M = mplayer format, similar to X
If the output format is not specified, w_scan defaults to create VDR-2.x channels.conf.

VDR version -oN

6 = vdr-1.6.x
7 = vdr-1.7.3 or higher

Help Level -Level

h = basic help
H = extended help for expert functionality

Some working examples, cobbled together from the basics given in the above table, are provided below. Note: Experts or experienced users may use some of the other w_scan options available, but this is not recommended. (For example, w_scan searches /dev/dvb/adapterX/frontendY for DVB/ATSC cards matching to option "-f", therefore specifying the adapter "-a XX" is not recommended.)


Note: As mentioned in the above table:
  • ATSC support requires a w_scan version >= 20080815
  • ATSC support was integrated in vdr-1.7.14, VDR output needs '-o 7'
  • DVB-S/S2 support requires a w_scan version >= 20090504
  • DVB-T2 support requires a w_scan version >= 20120111

Scanning ATSC VSB (United States, Over-the-Air)

$ w_scan -fa -A1 -c US -X

Scanning ATSC QAM annex B (United States, digital cable TV)

$ w_scan -fa -A2 -c US -X

Scanning DVB-T/T2 (Germany, Over-the-Air, VDR output)

$ w_scan -ft -c DE

Scanning DVB-S/S2 (Astra 19.2east, vdr-1.7.x)

$ w_scan -fs -s S19E2 -o 7

Scanning DVB-S (Thor 0.8west, vdr-2.x)

$ w_scan -fs -s S0W8

Scanning DVB-S (Hotbird, vdr-2.x, 4-port DiSeqC switch, hotbird at port 3)

$ w_scan -fs -s S13E0 -D2c

Note: ports are counting from '0'.

Scanning DVB-S/S2 (Astra 19.2east, vdr-2.x, SCR/EN50494 @ CH0/1076MHz/Satpos A)

$ w_scan -fs -s S19E2 -u 0:1400:A Note: Channel ID (0..7) needs to fit userband frequency. w_scan >=20140102.

Generating dvbscan tuning data

Exactly as above, just specify output format dvbscan with "-x":

$ w_scan -f <FRONTEND_TYPE> {-c <COUNTRY>,-s <SATELLITE>} -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.

Generating c/s/tzap tuning data

Exactly as above, just specify output format zap/czap/xine with "-X" (uppercase X):

$ w_scan -f <FRONTEND_TYPE> {-c <COUNTRY>,-s <SATELLITE>} -X >cc-Ttttt

Defining output charset

$ w_scan -f <FRONTEND_TYPE> -C <CHARSET> ...

Use 'iconv --list' for a list of possible output charsets, usually something like 'utf-8', 'iso8859-15'. Needs 20110410 or higher.

Also See

External Links