"Carl Hoff" <hof### [at] wtnet> wrote in message
news:402d6ba7$1@news.povray.org...
> > The IRTC accepts MPEG-1 files. For more information, see:
> > http://www.irtc.org/anims/rules.html#anims
> >
> > I'd stick with that format just in case you make something really
> > incredible and you want to submit it.
>
> Ok... I'll stick with MPEG-1.  I see the link above says
> "I", "P", and "B" frames are permitted.
>
> Are those sub flavors of MPEG-1?  I don't know what that
> means.

Nope -- those are the type of frames that make up an MPEG movie. They are:

I: Intra-frame, which is like a "keyframe" that is a totally complete image
that other frames are "derived" from...
P: Predictive frame, which is the next frame after an I (or P) frame that
only contains the changes from the previous I or P frame to make up the next
frame (that's how it gets the great compression -- it doesn't store every
picture, it stores what changes from the last picture).
B: Bidirectional frame, which is like a P frame, except it contains
information about the frame before AND after. Useful for rewinding.

A standard movie goes like this:

IBBPBBPBBPBBPBBPBB... repeat this kind of pattern.

B frames have the least quality, P frames have better quality and, of
course, I frames a full quality. Interlacing the P frames and the B frames
gives you the compression. Another pattern that would give better results
(but with a higher file-size) is IBPBPBPBPB...

If you use ppmtompeg (and POV-ray outputs PPM files nicely for each frame),
and you set up your ini file with a sequence like that above, you can
precisely choose which kind of frame you want where. So, let's say you have
a movie and you know exactly what frame a new scene starts. You could choose
to make those "I" frames. For parts of the movie where there is a lot of
blur, you can choose to include a lot of B frames because you don't need the
quality. For the rest, you can choose P frames. It's a little daunting at
first, but once you get the hand of ppmtompeg, you won't want to use dem
more fancy tools. It's like using POV-ray, really; why settle for some
crappy interface when you can set yourself free by using your mind only?


> > Also, if you're unemployed and looking for free stuff, I'd use
> > UNIX and get the netpbm library to build your MPEG file.
>
> I'm running Windows ME.  I guess I should have said that first.
> I'm not much of a UNIX person.

Well, that's okay, actually; they make netpbm for Windows too. I also have
the Mingw32 C/C++ compiler on my Windows XP box and it works grand. I
haven't tried the netpbm library on Windows, though, so I can't give any
opinions on whether it is as stable as Linux.

But, heck, just wipe that Windows box clean and put Linux on it. :-) Windows
ME was the worst OS M$ ever made. XP is nice, though; no complaints about
XP.

> > It's a little tedious, but you have very fine control over your
> > frames. Most package installers (like rpm, up2date,
> > dselect, RPMDrake, etc. based on your flavor of Linux or
> > UNIX) include netpbm now. If you want to go to the website,
> > go to: http://netpbm.sourceforge.net
>
> Most of that went over my head.  Package installers?  I think
> I need a very beginner level FAQ before all that makes sense
> to me but from the sound of what you said its just for UNIX.
> I did take a look at the side and see something that looks to be
> for windows:

They're just programs that install it for you so you don't have to muck
around with all the settings and whatnot.

> Netpbm for Cygwin (Windows)
>
> and
>
> Netpbm for Windows using Mingw32 and GNU Bash.
>
> But I don't know what Cygwin, Mingw32, or GNU Bash are.

Mingw32 is a C/C++ compiler -- I guess they mean you have to compile it
yourself (but I wouldn't be surprised if you can find a binary for it).

GNU Bash -- Bash is a shell. Think a DOS window only with UNIX commands.
You probably need Bash because netpbm works based on redirecting stuff from
one program to another using a pipe named STDOUT. That is a bit more
difficult to describe, so I'll illustrate it:

cat file.pmm | pnmtopng > file.png
would convert a pmm file to png.

DOS can't do more than one level of redirection so you'll need a shell. This
is something you'll have to explore if you want to save $$$, but it's not as
bad as it looks.

> > In my experience, if you're lazy (like me)
>
> Yes... its a little that.  But right now its more the lack of
> experience making animations.  I've simply never made one
> before.  I'm sure I can learn.  I didn't know how to use
> POV-Ray 4 months ago.

Learning is the whole trip -- what makes it worth it. Computer Graphics is a
field that you can dive deep and swim long and maybe never learn everything.
It also has a lot of rewards!

> > and don't want to go get the more obscure players, you'll
> > find that RealPlayer works fairly well for MPEG-1
> > animations and Windows Media Player absolutely flatulates
> > on it.
>
> I don't think playing it should be a problem.  I've got several
> players and I can view most of the stuff posted over in
> povray.binaries.animations.

Cool -- hey, do you have a suggestion for a good one? I still use
RealPlayer, but it doesn't work on all of them (it often cuts out before the
movie is done). What do you recommend?

> > Hope this helps!

> I'm not sure.  If you are telling me I need UNIX than
> probably not.  I was just wanting something I could
> feed the POV-Ray frames into and have it spit out a
> MPEG-1 file.  You've convinced me on the format
> atleast.  I might want something that would allow me
> to add sound at some point but I can live without that
> for now.  Above you talk about "very fine control over
> your frames".  What control is needed aside from
> what order to put them in?  I'll be making the frames in
> POV-Ray.

If you want to add sound, you could consider building your movies in Flash.
It's cheap, $400 cheap though. As far as the control, see my babbling about
IBP frames -- you'll see. You can't get a good movie in under 10MB for the
competition without some compression (well, maybe you can, but it would be
rough).

It looks daunting now, but once you get into it, it will all click. Computer
Graphics, as you know from learning POV-Ray, is really a lot of very easy
concepts wrapped around highly technical terms to make the more insecure
computer scientists look smart, imho :-)

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