On Thu, 09 Nov 2006 16:48:15 GMT, Tony Morgan
wrote:

To avoid audio clipping, I have (for some time) used Magix Cleaning Lab.
Applying Normalisation seems to do the trick. I've also found useful
(where video is shot in low audio situations) the Denoiser and Dehisser
facilites.

Where do you use it?
If you've got a signal with "flat-top" waveforms due to clipping at
any previous stage, normalisation can't rescue it. You'll still get a
nasty distorted sound, just quieter.

There ARE tools in the more advanced audio editing programs which
attempt to reconstruct a clipped waveform, with varying degrees of
success.

"Tony Morgan" wrote in message
...
In message , John Russell
writes

Snipped...

The combined bitrate for DVd Video and Audio cannot exceed 10684 BPS(or
something like that!). If you use PCM then that takes up 1500 BPS,
leaving the rest for video. If you use Dolby Digital 2.0 (i.e stereo)
you
can reduce the 1500 to say 256, and have either better quality video, or
longer recordings.


P.S. The DVD- video standard requires a minimum of either a PCM or an AC3
audio track. The AC3 track dosn't need to be 5.1, 2.0 will suffice.

I've been following this thread with some interest - but I'm puzzled. Does
bitrate equate with peak audio level(s) ?

No, they are unrelated. I think John was referring to bitrates because of
the huge difference between PCM and AC3 bitrates, and the fact that you can
adjust the AC3 peak during encoding from a bare PCM WAV file.

@ john - there's a good deal of confusion regarding maximum bitrates. I've
always thought that the maximum combined bitrate (audio+video+subpicture) is
10.08mbps, but that can only be managed in "bursts", with no reference to
what a "burst" actually is. The maximum sustainable combined bitrate is
9.8mbps. For simplicity, most people max out at 9.8mbps

However, when I went to Jim Taylor's FAQ for a reference to backup that
assertion, it appears "Maximum video bit rate is 9.8 Mbps." and "...the
maximum rate of combined elementary streams (audio + video + subpicture) is
10.08.".
http://www.dvddemystified.com/dvdfaq.html#3.4

It's all a bit of a moot point anyway - if you encode media for DVDR that
comes anywhere close to those levels, you'll end up with a disc that's
pretty much unusable in most DVD players.

In message , Laurence Payne
writes
On Thu, 09 Nov 2006 16:48:15 GMT, Tony Morgan
wrote:

To avoid audio clipping, I have (for some time) used Magix Cleaning Lab.
Applying Normalisation seems to do the trick. I've also found useful
(where video is shot in low audio situations) the Denoiser and Dehisser
facilites.

Where do you use it?

From my camcorder. The camcorder's AVC seems to prevent any clipping - I
assume because it's a fast-attack/slow-decay AVC circuit [1]

If you've got a signal with "flat-top" waveforms due to clipping at
any previous stage, normalisation can't rescue it. You'll still get a
nasty distorted sound, just quieter.

See above.

There ARE tools in the more advanced audio editing programs which
attempt to reconstruct a clipped waveform, with varying degrees of
success.

[1] This seems to be the case, because when doing any serious "set-up"
video work I use a MiniDisk recorder for sounds and use a clicker to
allow me to sync the MiniDisk sound with the camcorder's sound layer
(subsequently replacing the camcorder's sound with that from the
MiniDisk). On the camcorder's audio (though I eventually replace it),
you can hear the click at full volume, but the camcorder's audio level
immediately falls, taking about three seconds to slowly come up again.
The clicker, BTW, costs about 99p at doggie shops (used for training
fido).

--
Tony Morgan