Do any of you know a good video editing and sound editing and sound dubbing program to process CGI videos made by Poser?

How can I translate .AVI into a more compact form such as .MPG or similar?

How can I copy a movie segment while scaling down the size of every frame in it, to save file size?

I tend to use Premier, but that has now become rental software. For just quick converting and changing sizes of things I tend to use Bink/Smacker. I also tend to render out to a still image format and then compile them into an animation, often with Bink. That lets me stop a render part way through, edit things and get a better video quality by not going from one compressed video format to another.

1st one is Win only, 2nd is Mac/Win VirtualDub for editing and converting image sequence to .avi or .mp4 Handbrake for converting to .mp4

Personally, I use After Effects since I can composite several layers of images and add color correction/effects, etc.

-AniMajik

You can use pretty much any video application. It's better to render out images that can be converted into a single animation, since it prevents you from having to re-render everything in case of a crash or power outage. I've used afterFX, premiere, but now I just use iMovie because I have a mac.

iMovie will work in a pinch (I used it before I used FCP) but mostly use AE for compositing. I render out finished clips and then edit them together in Premiere CC (moved from FCP to PP) - but as you said, Mac only. (I am using Mac as well) Since the original poster mentioned AVI, I assumed Win and suggested accordingly.

-AniMajik

Thanks. Please where can I get or buy or download the various applications that you mention?

VirtualDub - http://virtualdub.org/

Handbrake - https://handbrake.fr/

Both above are free

Adobe After Effects or Premiere CC - http://adobe.com

$50.00/mon subscription

-AniMajik

Thanks. I already have VirtualDub - I thought that I had lost it, but I have found it again on my computer; it seems to operate to and from .AVI format only. I have just downloaded HandBrake. Adobe After Effects or Premiere CC at $50/month subscription= $600/year = rather expensive for me.

How about HitFilm?

Grab HitFilm Express its free link is at the bottom of page. http://Hitfilm.com

They have the commercial one they also offer a free one with a lot of the bells and whistles (if you want those its on 30 discount on the new one they just released). They have on the site some projects to get you going it will read in a sequence of images as well. There is also Fusion but thats a bigger program but also for single user they have it free. Do color grading and all kinds of other things. If you want the fusion link and can't find fusion video editor let me know. if you need additional audio stuff beyond whats there then the free audacity is good, then take that into hitfilm.

I highly recommend Hitfilm for anyone who would be working with 3d cgi, simply because it has a built in 3d compositing feature, and obj models are supported. Hitfilm is both a video editor, and a compositing software very similar to After Effects. The free version is well worth a look. For even more control and depth, I would recommend working with BlackMagic's Fusion. The base package is now totally free, and is considered to be one of the best compositing packages on the market. It's used by high level studios, and the node workflow allows you a greater flexibility for compositing shots than the layer based After Effects or Hitfilm would provide. It's got a much longer learning curve as well, but the power here is worth the time. Again, very much like Hitfilm, it's free, but you can also upgrade to the paid version if and when you outgrow it.

https://www.blackmagicdesign.com/products/fusion