Re: dual layer DVDs

From: gyoungblood (email suppressed)
Date: Tue May 15 2007 - 16:58:32 PDT

I use an app called "1-Click DVD" for PCs. It does not give me choice of bit
rate (which I don't understand in any case). It simply tells me that to copy
a movie from a dual layer DVD to a single layer disc, a certain amount of
compression will be necessary, and that's that. And why would it give me a
choice anyway? One assumes that the default compression is the minimum
needed to do the job, right? Why would it be otherwise? The app does allow
me to specify if I'm copying to a dual layer disc, which is why I asked if
that eliminates compression -- or, as you put it, results in a bit-for-bit

----- Original Message -----
From: "Ken Bawcom" <email suppressed>
To: <email suppressed>
Sent: Tuesday, May 15, 2007 5:25 PM
Subject: Re: [FRAMEWORKS] dual layer DVDs

> If you are copying an existing DVD, the compression/encoding has already
> taken place, and there is no advantage to copying it over at a higher bit
> rate. A bit-for-bit copy would produce as good a picture quality as was
> possible, equal to the original. To take advantage of the reduced
> compression/higher bit rate that a DL disc allows, you would have to do
> the encoding from the original source at the higher bit rate.
> A DL disc would allow you to record almost as much material at an XP bit
> rate as a SL disc will allow at an SP bit rate. Note that a DL disc has a
> little less than twice the storage capacity of an SL disc. Note also that
> if you record at a bit rate exceeding DVD specs, it may not play back on
> some players, especially older ones. That generally will not be a problem
> at the XP bit rate. There will still be some compression of the video at
> an XP bit rate, but you can record LPCM uncompressed audio with it.
> Ken B.
> Quoting gyoungblood <email suppressed>:
>> Frameworkers,
>> I'm thinking to purchase a dual layer DVD read-write drive on the
>> assumption that it will allow me to copy DVDs with less compression than
>> single layer. Am I right? If so, what does "less compression" mean? If I
>> copy a dual layer disc to another dual layer disc, will there be no
>> compression? Are there any other problems with dual layer copying? Can
>> anyone recommend a website that explains all this?
>> Gene Youngblood
>> Department of Moving Image Arts
>> The College of Santa Fe
>> 1600 St. Michael's Drive
>> Santa Fe, NM. 87505 USA
>> Vox: +1.505.473.6406
>> Fax: +1.505.473.6403
>> Office: email suppressed
>> Home: email suppressed
>> __________________________________________________________________
>> For info on FrameWorks, contact Pip Chodorov at <email suppressed>.
> "Those who would give up essential liberty
> to purchase a little temporary safety
> deserve neither liberty, nor safety."
> Benjamin Franklin 1775
> "I know that the hypnotized never lie... Do ya?"
> Pete Townshend 1971
> __________________________________________________________________
> For info on FrameWorks, contact Pip Chodorov at <email suppressed>.

For info on FrameWorks, contact Pip Chodorov at <email suppressed>.