From: AW <arne_woerner@yahoo.com>
To: linux-media@vger.kernel.org
Subject: Re: PCTV USB2 PAL / adds loud hum to correct audio
Date: Sun, 13 Feb 2011 00:41:05 -0800 (PST) [thread overview]
Message-ID: <429131.49602.qm@web30308.mail.mud.yahoo.com> (raw)
Andy Walls wrote:
> I find audio at 8 ksps very unusual for a TV capture device.
>
I tried it with pulseaudio at 44100 samples/sec
and with some commercial tuned in...
(no big copyright problem hopefully) :-)
i used this command:
parec --device=alsa_input.hw_1 > blah.raw
resulting raw data: http://www.wgboome.de./blah.raw
> The data set contains no large positive values
> (nothing in the range 0x1000-0x7fff).
>
Now the noise is in the positive range, 2...
I made a new filter program (see appendix),
that produces acceptable but still distorted sound.
filter output: http://www.wgboome.de./blah.ogg
> The valuex 0x10 and 0x80 do remind me of the YUV values for black: Y =
> 0x10, U = 0x80, V = 0x80. Maybe some video data is getting thrown in
> with the audio?
>
sounds good...
because: the unwanted data changed its range now...
-arne
appendix:
...
(buf[i]/256>=0x80 && buf[i]/256<0xC0) ||
(buf[i]/256>=0x40 && buf[i]/256<0x80)) {
...
next reply other threads:[~2011-02-13 8:41 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-02-13 8:41 AW [this message]
-- strict thread matches above, loose matches on Subject: below --
2011-02-17 9:24 PCTV USB2 PAL / adds loud hum to correct audio AW
2011-02-12 20:22 AW
2011-02-12 21:33 ` Devin Heitmueller
2011-02-12 21:44 ` AW
2011-02-12 23:34 ` Andy Walls
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=429131.49602.qm@web30308.mail.mud.yahoo.com \
--to=arne_woerner@yahoo.com \
--cc=linux-media@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.