Various small test/sample programs for the Linux DVB API Version 2/3

The default devices used by the test programs are generally
/dev/dvb/adapter0/*0, and can be overridden using environment
variables:

  FRONTEND=/dev/dvb/adapter0/frontend0
  DEMUX=/dev/dvb/adapter0/demux0
  DVR=/dev/dvb/adapter0/dvr0
  AUDIO=/dev/dvb/adapter0/audio0
  VIDEO=/dev/dvb/adapter0/video0
  NET=/dev/dvb/adapter0/net0


diseqc		: Send various diseqc sequences on a SAT frontend.
		  Best used with a diseqc test box with some LEDs to
		  show the result of the commands.
set22k		: Legacy tone switching for SAT frontends.
setvoltage	: Legacy voltage switching for SAT frontends.

setpid		: Set video and audio PIDs in the demux; useful only
		  if you have a hardware MPEG decoder.
video		: A tiny video watching application, just starts capturing /dev/video
		  into /dev/fb0.
		  WARNING: May crash your box or mess up your console!

test_sections	: Hex dump of section data from stream.
test_sec_ne	: Like test_sections, but also test Not-Equal filter mode.
test_pes	: Hex dump of PES data from stream.
test_tt		: Demonstrate teletext decoding from PES data.
test_av		: Test audio and video MPEG decoder API.
test_vevent	: Test VIDEO_GET_EVENT and poll() for video events
test_stc	: Test DMX_GET_STC.

test_stillimage : Display single iframes as stillimages
		  iframes can be created with the 'convert' tool from
		  imagemagick and mpeg2encode from ftp.mpeg.org, and must
		  have a supported size, e.g. 702x576
		  ($ convert -sample 702x576\! test.jpg test.mpg)

test_av_play	: Test playing MPEG PES (VDR format) from a file
test_dvr_play	: Test playing MPEG TS from a file (don't try, driver is broken)

test		:
test_audio	:
test_dmx	:
test_dvr	:
test_front	:
test_switch	:
test_video	: Play video-only file on /dev/dvb/adapter0/video0