Actually you can use any Direct-X compatible codec that is installed on your system so it is possible to have multiple MPEG encoders available to VideoFactory. However, i do believe that is correct that Cinepak is for AVI only.

I don't know a whole lot about video, but I was able to open VF, render the "alaska trip" file as an MPEG with the ManiConcept codec, then insert that MPEG into a program called Video Man (http://www.stoik.com/products/videoman/index.html) and output it as an MPEG using the Cinepak codec.

As I said, though, I don't know enough about codecs to really know what's going on there, though.

Regardless, I do know PowerPoint and how it handles multimedia, and that's the ultimate end for this particular MPEG -- it needs to be inserted into a PPT file. And with PPT using the Windows MCI to play back video, it's important to stay with standard codecs. Cinepak is one I can count on being available on most systems, so it's more reliable for my use than the MainConcept codec is.

I can always go with an AVI using the Cinepak codec, but I believe MPEG will be smaller, so I'd prefer to use it.

Thanks for the info. At least I won't bang my head against the proverbial wall trying to find a way to add codecs to the export list in VF.

The size of the file will be related to the compression of the codec, not the file type it's in. If you use the same Cinepak compression factor for rendering, then the file would be the same size as either AVI or MPEG ... if indeed you can get MPEG to use Cinepak.

Since you've seen this before, my best guess is that the file really was a AVI file that had a .mpg extension. Most players are smart enough to ignore the extension at the end of the filename and determine the type by reading the header information inside the file itself. In this case, the player would probably see that it was actually a AVI file and read it accordingly.

Most all computer systems out there have the MPEG-1 codec installed by the OS these days. You should be able to play back an MPEG-1 file on almost any system. Of course, this would be an MPEG-1 file using MPEG-1 compression, not Cinepak.

I think like many people, you have codecs and media containers confused.

First, when you are playing a "video", that file acutally contains both audio and video data, right? Yet, you only clicked on one file. So obviously, that file is a "container" that holds audio and video data. There are numerous ways to arrange that data leading to different continer formats like AVI (Audio and Video Interleave), Quicktime and MPEG (Moving Picture Experts Group).

Second, video and, to a lesser extent, audio data is huge. Try creating a "Uncompressed" AVI in Video Factory. Huge, right? Anyway, there are algorithms that reduce the size of video and audio data called codecs (Compressor/Decompressor). These codecs can be used to reduce the data inside the container format. Furthermore, a codec is specific to a container format.

Now, there can be some confusion since sometimes a container format and media container have the same name (MPEG, Real, Windows Media). Plus, some codecs, like Cinepak, have two different versions, one that works with AVI's, one that works with Quicktime's. They are two separate codecs thought, Cinepak for AVI and Cinepak for Quicktime. You can't use Cinepak for AVI codec to compress a Quicktime.

If all this is confusing, think of a media container as a Word file and a codec as a font.

Thanks for this info, Chienworks. I didn't try creating an AVI with the Cinepak codec, so I've nothing to compare size with. What you say about equal size makes sense--I wondered if they'd be the same size since the specific codec sets the compression rate, but I mistakenly assumed the MPEG would be smaller for some reason. Duh! When it comes to something actually being an AVI with an .mpg extension, well, that's where I start getting really confused!

At any rate, the MPG I created with the Cinepak codec (by passing through VideoMan) does play in PowerPoint. The one I created with VF and the MainConcept MPEG-1 codec doesn't. I'll have to try the same with AVIs, just to see what plays and what doesn't.

Mmm, well, actually, I do understand the concept behind codecs as opposed to the type of file the video ends up as. (It may not seem as if I do, but really, I'm okay there!)

What I guess I don't really understand, though, is the difference between, say, an AVI and an MPEG which both use the same codec for compression. As you mentioned, "a codec is specific to a container format," but MPEG and AVI are different.

As in my example earlier, I was able to create an MPEG with a Cinepak codec, but as Chienworks mentioned, that was probably actually an AVI with an MPG extension. That's where I get confused.