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> I have yet to see any posts about users results with the card.
> Those using one, how is the recording quality of the card,
> compared to
> non-encoding cards?

Looks better, sounds better. Uses a higher bitrate though, so the
files are larger.

> Also does the btaudio module work with the PVR-250?

Why would you want btaudio?

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Robert-

How much larger? I was under the impression that although the card can use
all sorts of bitrates, the driver was locked at a certain bitrate
(something like 16megabits/sec, which came out to about 7.2GB per hour),
which scared me away from using the card.

In light of the CompUSA thing going on, my curiosity has again been piqued,
but I've only got a 40GB drive, and 7GB/hr would be somewhat problematic
for me.

Thanks for any insight.

-Jeff



"Robert Kulagowski"
<rkulagowski@thrupoint To: "'Discussion about mythtv'" <mythtv-users@snowman.net>
.net> cc:
Sent by: Subject: RE: [mythtv-users] PVR-250 quality?
mythtv-users-bounces@s
nowman.net


04/28/2003 03:37 PM
Please respond to
Discussion about
mythtv







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> I have yet to see any posts about users results with the card.
> Those using one, how is the recording quality of the card,
> compared to
> non-encoding cards?

Looks better, sounds better. Uses a higher bitrate though, so the
files are larger.

> Also does the btaudio module work with the PVR-250?

Why would you want btaudio?

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_______________________________________________
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http://lists.snowman.net/cgi-bin/mailman/listinfo/mythtv-users

With my current Wintv card I get much better audio quality using btaudio
rather than the pass-thru cable. Thats why I was wondering if the
btaudion module worked with the PVR-250 so I could still use it the same
way.

On Mon, 28 Apr 2003, Robert Kulagowski wrote:

>
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> Hash: SHA1
>
> > I have yet to see any posts about users results with the card.
> > Those using one, how is the recording quality of the card,
> > compared to
> > non-encoding cards?
>
> Looks better, sounds better. Uses a higher bitrate though, so the
> files are larger.
>
> > Also does the btaudio module work with the PVR-250?
>
> Why would you want btaudio?
>
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>
> iQA/AwUBPq2DA/c1NpCTlP0JEQKwjACg5zqlENGsO1HKxtWdQn+yfQqhbNUAoNSi
> yKnBhjJMWH0i/JGwP09bGZNu
> =HQPS
> -----END PGP SIGNATURE-----
>
> _______________________________________________
> mythtv-users mailing list
> mythtv-users@snowman.net
> http://lists.snowman.net/cgi-bin/mailman/listinfo/mythtv-users
>

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On Mon, Apr 28, 2003 at 04:08:59PM -0400, jeff@burstable.net wrote:
> With my current Wintv card I get much better audio quality using btaudio
> rather than the pass-thru cable. Thats why I was wondering if the
> btaudion module worked with the PVR-250 so I could still use it the same
> way.

the PVR-250 creates a MPEG-2 stream that contains both video and audio. You
don't need to read two seperate sources.

Jeff

- --
- ----------------------------------------------------------------------------
Computer Science is as much about computers as astronomy is about telescopes
-- Edsger Wybe Dijkstra (1930-2002)
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> Looks better, sounds better. Uses a higher bitrate though, so the
> files are larger.

By default, but doesn't have to be. I just modified my ivtv driver to
use 2mbit/8mbit max instead of the default 8mbit/16mbit max, and the
quality is still good. At some point the driver will support changing
this without having to recompile..

-jim

jeff@burstable.net wrote:

>With my current Wintv card I get much better audio quality using btaudio
>rather than the pass-thru cable. Thats why I was wondering if the
>btaudion module worked with the PVR-250 so I could still use it the same
>way.
>
btaudio provides /dev/dsp, a soundcard interface for (in this case)
reading/recording uncompressed audio, matching the /dev/video to
read/record the uncompressed video.

The PVR card compresses itself and of course includes audio in the MPEG
stream, so it reads the audio internally and MythTV reads it together
with the video stream in a single MPEG stream.

No need for btaudio or the like.

> With my current Wintv card I get much better audio quality using btaudio
> rather than the pass-thru cable. Thats why I was wondering if the
> btaudion module worked with the PVR-250 so I could still use it the same
> way.

You don't need it -- the audio is muxed into the MPEG stream. There
are no passthrough cables; effectively you're getting btaudio
functionality automatically.

-jim

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> How much larger? I was under the impression that although
> the card can use
> all sorts of bitrates, the driver was locked at a certain bitrate
> (something like 16megabits/sec, which came out to about 7.2GB
> per hour),
> which scared me away from using the card.

It's actually closer to 8Mbps, despite what's being printed out.
Here's a 35 minute episode of "Friends"

2,291,632,064 Apr 25 11:10 1005_20030424190000_20030424193500.nuv


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> Thats why I was wondering if the btaudion module worked with the
> PVR-250 so I could still use it the same way.

The PVR250/350 produce a muxed MPEG2 stream. There is no need for an
external sound card to capture the audio. Think of it as built-in
btaudio that works.

See the HOWTO: http://www.mythtv.org/docs/mythtv-HOWTO-3.html#ss3.1

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Does the ivtv driver use static rate encoding or variable rate encoding?
This would make a huge difference in how much space the mpeg takes up.

schu

Robert Kulagowski wrote:
>
>
>>How much larger? I was under the impression that although
>>the card can use
>>all sorts of bitrates, the driver was locked at a certain bitrate
>>(something like 16megabits/sec, which came out to about 7.2GB
>>per hour),
>>which scared me away from using the card.
>
>
> It's actually closer to 8Mbps, despite what's being printed out.
> Here's a 35 minute episode of "Friends"
>
> 2,291,632,064 Apr 25 11:10 1005_20030424190000_20030424193500.nuv
>
>

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> Does the ivtv driver use static rate encoding or variable rate encoding?
> This would make a huge difference in how much space the mpeg takes up.

Variable, 8Mbps base, 16Mbps peak, is the default.

-jim

So, what resolution was that show recorded at?



On Mon, 2003-04-28 at 15:18, Robert Kulagowski wrote:
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
>
> > How much larger? I was under the impression that although
> > the card can use
> > all sorts of bitrates, the driver was locked at a certain bitrate
> > (something like 16megabits/sec, which came out to about 7.2GB
> > per hour),
> > which scared me away from using the card.
>
> It's actually closer to 8Mbps, despite what's being printed out.
> Here's a 35 minute episode of "Friends"
>
> 2,291,632,064 Apr 25 11:10 1005_20030424190000_20030424193500.nuv
>
>
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> =2Ui7
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>
> _______________________________________________
> mythtv-users mailing list
> mythtv-users@snowman.net
> http://lists.snowman.net/cgi-bin/mailman/listinfo/mythtv-users

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> So, what resolution was that show recorded at?

480x480.

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