From: Ken Bawcom (email suppressed)
Date: Tue May 15 2007 - 17:18:06 PDT
I see, I didn't realize that you were copying FROM a DL disc. That
would take a LOT of compression to fit on a SL disc, assuming that the
DL disc was near capacity. Yes, transfering from a DL disc to a DL disc
should eliminate any additional compression, producing an exact copy of
the original.
I do my burning on a DVDR with a 160GB HDD, so have little familiarity
with PC burners. I would guess that your app is being polite, and
letting you know that you will have a more compressed, lower quality
image, when transferring to a SL disc, from a DL disc, so if that is
not acceptable, you can do something else. Or, does it allow you the
possibility of transferring part of the DL to a SL disc, and then the
remainder to a second SL disc? It probably automatically selects the
optimum bit rate to make the original disc fit on the copy, as you have
guessed. Likewise, when copying from a SL disc to another SL disc, it
makes a bit-for-bit copy, at the same bit rate as the original. There
would be no point in making a copy at a higher bit rate.
Ken B.
Quoting gyoungblood <email suppressed>:
> 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 copy.
>
>
> ----- 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>.
>
>
>
"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>.