OK.  After two posts to ivtv-users over a month and no responses, I've
finally taken the final step of research and figured out why I was having
issues with my ivtv-0.8 setup.  I figure if I've managed to figure this out,
I should post and share.

 

The short short version:

 

If you see ugly static, fuzziness, ghosting, or contrast flicker on analog
recordings, particularly recordings with clear solid backgrounds, try
running:

 

v4l2-ctl -C temporal_filter

 

This returns the value of the PVR's temporal filter setting.  If the value
returned is 0, try:

 

v4l2-ctl -c temporal_filter=8

 

And see if that clears up the recording.  This problem may only apply to
MythTV users (which starts with a default dimension other than 720x480)
using ivtv 0.8.

 

The short version:

 

I have a PVR-150. 

 

* I am running Slackware Linux with a 2.6.16.2 kernel

* I am running ivtv 0.8.1 (and previously 0.8.0)

* I get an annoying static, or flicker, or ghosting, or contrast issues on
my recordings.

* This annoying static is similar to the TV quality I see downstairs.

* The static did not appear on a digital clean signal (e.g. DVD-Player,
Digital Cable) but did appear on analog cable.

* This ghosting did not appear on my old Windows box running SageTV, as if
the static were magically cleaned up.

* This ghosting did not appear on my old Windows box (same hardware) running
a Linux LiveCD boot (Slax) with ivtv-0.6.3, as if the static were magically
cleaned up.

* This ghosting did not appear on my new Linux server running the same
LiveCD and ivtv-0.6.3, as if the static were magically cleaned up.

 

The solution came to me reading a post made in (and misposted into) the
ivtv-devel group:

 

http://www.gossamer-threads.com/lists/ivtv/devel/33583

 

Apparently for the ivtv-0.8 series, the temporal filter defaults to 0.  I'm
guessing the temporal filter is an on-card ability to clean up a noisy
analog cable signal.

 

I'm going to ask generically about the onboard filters in another message.

 

I'm happy!  After 5 weeks of tracking down a noisy signal, running through
my attic, moving my PVR card around from one system to another, I've managed
to diagnose the problem.  (OK, maybe it took 3-4 evenings, but I've got
kids! )

 

Trevor Bradley

Surrey, BC

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