Adam,
I tune video1 by tuning video0 with tvtime. Playback in tvtime freezes
for a few seconds after I issue a cat /dev/video1 command, then resumes.
MPEG capture on video1 is intermittent.
The picture during playback of the resulting mpeg file may be good or it
may be all noise, or it may be good with a bit of noise at the top
of the screen. Audio works in all three cases.
wonders if results would be better if one had a better way to tune
video1.
Toney

Toney wrote:
Adam,

I tune video1 by tuning video0 with tvtime. Playback in tvtime freezes
for a few seconds after I issue a cat /dev/video1 command, then resumes.

MPEG capture on video1 is intermittent.

The picture during playback of the resulting mpeg file may be good or it
may be all noise, or it may be good with a bit of noise at the top
of the screen. Audio works in all three cases.

wonders if results would be better if one had a better way to tune
video1.

Instead of using a framegrabber app with the raw video0 device, just try
to use v4l2-ctl or qv4l2 to control the video1 encoder device itself.
These tools are located in the v4l2-apps directory of the v4l-dvb hg
repository.

A good way to test is to run "mplayer /dev/video1" while controlling it
with qv4l2.

Good Luck!

Michael Krufky wrote:
Toney wrote:

>Adam,
>>
>I tune video1 by tuning video0 with tvtime. Playback in tvtime freezes
>for a few seconds after I issue a cat /dev/video1 command, then resumes.
>>
>MPEG capture on video1 is intermittent.
>>
>The picture during playback of the resulting mpeg file may be good or it
>may be all noise, or it may be good with a bit of noise at the top
>of the screen. Audio works in all three cases.
>>
>wonders if results would be better if one had a better way to tune
>video1.
>
>
Instead of using a framegrabber app with the raw video0 device, just try
to use v4l2-ctl or qv4l2 to control the video1 encoder device itself.
These tools are located in the v4l2-apps directory of the v4l-dvb hg
repository.

A good way to test is to run "mplayer /dev/video1" while controlling it
with qv4l2.

Good Luck!
--

Thanks for the tips.

I downloaded, compiled, and installed the works from
http://linuxtv.org/hg/v4l-dvb. Tuning seemed stronger and picture
quality seemed better to me with the v4l-dvb
<http://linuxtv.org/hg/v4l-dvbsoftware than with just my 2.6.18 kernel
modules. Dev/video1 disappeared until I manually inserted the cx88
blackbird module.

v4l2-ctl: It took my a while to realize I needed actual frequencies and
to discover how to unmute. But finally, "./v4l2-ctl -d 1 -f 61.25
" gave me a very nice MPEG2 stream. It does pixelate /
go cubist on me occasionally. Mplayer /dev/video1 works very nicely,
though at first I was getting double, slightly out of synch audio
streams. But this was because I have a black-to-white CD audio cable
connecting J3 on the PTV-305 to AUX on my sound card. Muting AUX got
rid of the extra audio stream.

Running qv4l2 on my system yields the following:

X Error: BadDevice, invalid or uninitialized input device 169
Major opcode: 147
Minor opcode: 3
Resource id: 0x0
Failed to open device
X Error: BadDevice, invalid or uninitialized input device 169
Major opcode: 147
Minor opcode: 3
Resource id: 0x0
Failed to open device

The qv4l2 window comes up in X, but tuning channels with it does not
work, and the frequency box is read-only, showing only "-1" or
occasionally 0. I have an nVidia FX5500 card, SiS 648FX chipset, and
Ubuntu Dapper Xorg. I </>tried
nVidia proprietary, nv, and vesa drivers, all with a similar result.
well. v4l2-ctl works fine. </>

Loads of fun!