On Wed, 2005-05-18 at 16:19 -0700, Steven M. Schultz wrote:
> On Wed, 18 May 2005, Matt wrote:
> At the risk of sounding silly why not put the Mac on the network? ;)
Excellent question! 'Cause its not my Mac! These are stand-alone suites
for a local shop. We often work for them.
> Actually sneaker net can be faster
Agreed!! I just moved 300GB with the swap of a cable!
> So far I've been able to retain using mpeg2enc for the encoding and it
> does a very good job once you have grasp on the options to use and
> how to pre-process/filter the incoming data (when doing analog->digital
> conversions).
In our case we are coming from an almost entirely digital process.
We typically generate tga's and then do our conversions from there.
> For myself I've moved more and more of the acquisition, initial
> processing and eventual authoring *to* the Mac.
>
> For generation/compositing there's Motion at the entry level and
> Shake at the high-end but Shake is quite expensive (but is available
> for Linux I believe).
Fair enough. They have some mighty nice tools. We do most of our work in
blender.
Very cheap to scale. Not so with Mac OS X and almost ALL of the major
rendering systems are available for Linux (notable exception being
lightwave). This goes either way with mac, some are available and some
are not. After upgrading the macs at this guys office though, we
couldn't yet afford to do what we do with macs (but I do drool over
their hardware.)
> > generated 3d stuff, so the encoding is critical. My experience says that
> > animations always seem to suffer more than video during encoding. And my
>
> Hmmm, ok - generating animations (modeling/compositing) isn't
> something I've worked with a lot.
Any time you need something like that, give us a holler! We are more
about the modeling/animation. We could easily do some nifty menus and
such.
> I do see a lot of animation but...
All great info! Some I knew, some is new! Thanks much. Filed for later
use.
> Oh - and avoid JPEG at any stage of the process!
See above. We have more problems with jpegs. Everybody thinks jpegs are
great, until they see the end result. I love them for single images used
in the right place, but when will people realize that jpegs are NOT the
end all be all of digital imagery!
> [Compressor] ... doesn't implement DPME (Dual
> Prime Motion Estimation) which I find helps improve the picture when
> not using B frames, the choice of GOP size is limited
Is there a specific time when not using B frames is a plus? Are we looking at
space savings?
My recent tests show marked improvement in quality with B frames being
used.
> One thing I am looking forward to in DVDSP4 is the new Compressor
> 2.0.x which can do HD resolutions (both MPEG-2 and H.264) - that
> will be fun to play around with.
Just got to mess with it at NAB, very cool. Very, very cool. I look
forward to creating for H.264 dedicated devices one of these days. I saw
one JVC (or was it pioneer) dvd player at NAB that was in the apple
setup.
> Mencoder's rate control wasn't as good as mpeg2enc's the last I heard.
> For quite a while (even fairly recently) folks were having trouble
> getting 100% compliant streams out - sometimes it would work, other
> times the standalone players would object to the files. Your Mileage
> May Vary of course :-)
Just did a comparison of mencoder and mpeg2enc. I am VERY pleased with mpeg2enc
output.
If I can keep this up I won't need compressor any longer.
> > 2. I have already noticed that mpeg2enc does not appear to perform 2
> > pass encoding. Is this really a detriment?
>
> Not really. For a 1 pass encoder it's one of the better ones (the
> rate control has become amazingly good - little overshoot and quick
> recovery). It's also quite fast - the bottleneck is rarely if ever
> the encoder but instead the filtering/pre-processing.
Can you be more specific as to what you mean by
filtering/pre-processing? Any direction toward literature would be
welcome.
>
> About all I've seen two pass encoding do is almost double the encoding
> time <grin>
I have to admit, with mencoder, it didn't help _much_.
A little, but not enough to warrant using it. I'm sure that some of that was
PBKAC.
> How long of a project is it planned to be? With the right options
> you should be able to get down to ~7500 and get 85-90 minutes on a
> single layer piece of media.
Small. Less than 10 minutes. I just wanted to understand the
limitations. It looks like they are nearly the same for compressor OR
mpeg2enc, if used judiciously.
> Were you generating the data at 24 or 30fps? You can save ~20% on
> the bitrate (or viewed another way you can keep the same bitrate and
> get a ~20% increase in quality ;)) by using the film rate (well,
> 24000/1001 ;)) instead of 30. That would also make converting to the
> 25fps ("PAL") format simpler - a modest speedup instead of going from
> 30 to 25.
Nearly always 30, because our clients work in 29.97. For our dvd work I will
chop it down.
That makes great sense. I forgot that dvd's can work in 24fps!
> > 4. Obviously compatibility with hardware players is a clear concern, and
> > I have read the dv-to-dvd.txt, so those tips are in my head. Are there
> > any other pitfalls a person should be aware of when mastering a dvd with
> > these tools?
>
> The obvious (and it is a VFAQ - Very Frequently Asked Question ;))
> one that comes to mind is that you can NOT append/catenate multiple
> files seamlessly with dvdauthor - you'll have stutter/stops/gaps and
> so on at the join/splice points(depending on the player used). DVDSP
> has no problem joining multiple files together in a single track.
At the risk of being off topic, do you mean you can't set dvdauthor to
play #1_mpeg into #2_mpeg into #3_mpeg without flaws? That could be a
serious problem.
> The other thing which I do fairly often is 'multi' and 'mixed' angle
> DVDs. Trivial to do with DVDSP but not with the other tools as far
> as I know (mpeg2enc can generate .m2v files suitable for multi-
> angle DVDs). Are you going to need multiple audio tracks? Multiple
> subtitle streams?
Generally one track, only occasionally with more than 2 channels and I have
never needed a subtitle stream.
That just doesn't (yet) fit into our work.
> > I will be acquiring the dvd books suggested by Mr. Schultz asap. With
> > blue ray and the rest, I suspect we will be changing technologies again
> > pretty quickly. But until then...
>
> I'll probably get a blu-ray recorder for data storage as soon as
> possible. But in a few weeks I'll be experimenting with authoring
> HD-DVD - one of the new features in DVDSP4...
I got a chance to play with all the latest and greatest from apple. Nice.
Smooth. Shake
is awesome but it is also a processor hog. I am glad Apple hasn't killed the
Linux
version, but I can see it coming. I guess the BSDs have to have their place. ;)
Thanks for all the help! I look forward to putting some things together.
And if nothing else I will know a lot more about the authoring process.
Thanks again,
Matt
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