[Extractstream [MM]] Re: Using LSX to encode DVD

[John Douglass]

On Mon, 30 Dec 2002 11:31:11 -0800,Scott Alfter <scott@alfter.us
wrote:

>On Sun, Dec 29, 2002 at 10:26:49PM -0800, John Douglass wrote:
>> On Sun, 29 Dec 2002 14:47:55 -0800, you wrote:
>> 
>> >I've been using TMPGEnc to encode my extracted videos from my Tivo to
>> >DVD, so I can burn some shows off the machine.  I've been using
>> >JDouglass's technique to do so =
DVD2AVI->VFAPI->VirtualDub->TMPGEnc->DVD.
>> 
>> Actually, my technique is more like DVD2AVI->TMPGEnc->DVD.
>
>That sounds not too different from what I do, except I throw Avisynth
>between DVD2AVI and TMPGEnc (it offers much more flexibility in editing)=
 and
>I encode to SVCD.

Um, care to share your Avisynth script?  I was just starting to get
into avisynth before I re-installed WinXP.

>> >Anyways, since I am encoding what amounts to be about 3 hours of =
video
>> >per show, its taking me about 16 hours per video to encode.
>> 
>> Count your blessings.  It takes me 10-times the show length to encode.
>> So a 1 hour show, actually only 45 minutes sans adverts, takes me
>> almost 450 minutes to transcode.
>
>Ouch.  With settings similar to the OP, I can encode the typical =
"1-hour"
>show (sans ads) in somewhere around 3 hours.

You have this on your website?

>> >- I get very jumpy video when viewed on a TV (I used to get the same =
thing with TMPGEnc until I used jdouglass's suggestion and used the Top Field First setting in TMPGEnc
>> 
>> Ah, then you have a Stand-alone tivo, as Dtivo's take "Bottom field
>> first".  As for why LSX would muck it up... Just in case LSX is
>> backwards, did you try LSX's other setting?
>
>One thing you might try to speed up encoding and improve picture quality=
 is
>inverse telecine.  Since most TV starts out on film at 24 fps, preparing
>film for broadcast typically involves slowing it down slightly to 23.976
>fps, then creating one additional frame for every group of four frames =
to
>bump the final framerate up to 29.97 fps.  You can reverse this process =
to
>get progressive-scan video at 23.976 fps.  This makes the "bottom =
field/top
>field" setting irrelevant.  Since more bits are allocated to each frame,
>you'll get better image quality.  If I'm not mistaken, progressive-scan
>video is also easier to encode than interlaced video...in any case, =
you're
>only encoding four-fifths as many frames, which has to amount to a
>significant speed boost.  Both SVCD and DVD-Video support this
>framerate...DVD players will telecine video on-the-fly for playback.
>
>There's a fairly decent inverse telecine filter available for Avisynth. 
>VirtualDub also has a good inverse telecine filter, but you'll need to =
write
>out a huge intermediate file for encoding since VirtualDub's inverse
>telecine filter doesn't work when you frameserve.
>  _/_   Scott Alfter
> / v \  salfter@salfter.dyndns.org
>(IIGS(  http://salfter.dyndns.org   Top-posting!

Let us know how you do this, please.  Especially the part about
avoiding sync issues by frameserving.

Thanks!

John

--
"C makes it easy to shoot yourself in the foot;  C++ makes it harder, but when
you do it blows your whole leg off."    -- Bjarne Stroustrop, inventor of C++