Compressing help needed

[Rawhead]

I had a wmv file that was originally 29 mb. 320x240 video- mono 8 bit audio.
the file is 55 minutes long.

I wanted to do some editing on it so I converted it to an AVI - 720x480 @29.97 FPS 16 bit mono. It was WMV1 encoded so I had to re encode it using asfTools. The conversion took 8 hours and I now have an 11.2 GB file.
For comparison, I just converted a different 320x240 WMV file to AVI which took 1 second.

I didn't edit anything yet, but just started playing with it and tried to compress it to Mpeg. I compressed to Mpeg2 for DVD and the file is now 11.5 GB. then I took the AVI file and converted it to Mpeg 1 (mono 16 bit at 720x480 and that file is now 11.7 GB.

I know I can reduce the frame size and Frame rate in some progams I have but I've taken standard quicktime or AVI movies that are 8 gigs and converted them to 300 mb MPEG files before. I'm just not sure what I used to do it the other times.

All I have now is an MPEG1 encoded 11.7 GB file (audio is not important on this right now). How the heck do I get this back to a smaller size?

TIA

[fmctm1sw]

I've had a few beers so maybe that is why I am uncertain on what you are trying to do. Do you want to make a DVD compliant file to play on a standalone player? Do you want to make a WMV file? If you are interested in the smallest file size, you should probably go with WMV. You can knock the framerate down to 16 or 18 and use non DVD standard frame sizes (like 320x240). What do you want to do?

[jimmalenko]

Not sure exactly what you are trying to. I gather that all the conversions are in an attempt to get the file size down. Conversion = quality loss, so you want to limit the number of times you convert from one format to another.

Whenever I want to edit WMV I use Windows Movie Maker 2 in the timeline mode and save directly back to WMV. That simple.

[Rawhead]

Sorry if I wasn't clear in my goals but I didn't really have any goals except to get the file into the smallest mpg I could without reducing the size more than 360x240. The reason I turned it into an AVI in the first place was to do some extensive color editing on it but that was a different story all together.

I would think that I could get his file down to at least 600 MB but so far no go. the smallest I got was nearly 3 GB. And like I mentioned, when I converted the AVI it to MPEG-2 for DVD, the file came out 11.5 GB - this is with 16 bit mono Audio. I've authored DVD's before and I've never seen a file get that big that was an hour long AVI. The Mpeg 2 file was actually larger than the AVI file.

I guess the original must have been only like 10 FPS in order for it to be 29 mb.

[jimmalenko]

Sorry if I wasn't clear in my goals but I didn't really have any goals except to get the file into the smallest mpg I could without reducing the size more than 360x240. The reason I turned it into an AVI in the first place was to do some extensive color editing on it but that was a different story all together.

I would think that I could get his file down to at least 600 MB but so far no go. the smallest I got was nearly 3 GB. And like I mentioned, when I converted the AVI it to MPEG-2 for DVD, the file came out 11.5 GB - this is with 16 bit mono Audio. I've authored DVD's before and I've never seen a file get that big that was an hour long AVI. The Mpeg 2 file was actually larger than the AVI file.

I guess the original must have been only like 10 FPS in order for it to be 29 mb.

FPS and the size of the frame dosn not contribute to file size at all. The combined Video and Audio bitrates multiplied by the running time is how you work out the size. I would suggest yuo choose a video codec such as DivX and use MP3 audio and you will notice a massive difference in the size of your file. It sounds like you might have saved uncompressed, which would result in the file sizes youa re talking about.

[Rawhead]

Ok, now we're getting somewhere. So the smaller the bit rate, the smaller the file size. and you're saying that no increase or decrease in the size of the actual frame or the frame rate has anything to do with the size of the file? I guess I'll have to take your word for it because I know nothing about it (obviously


Unfortunately, TMPGEnc doesn't recognize the file i was originally talking about but I tried it on another ASF file.

Original file was a 91 mb. 320x420 and stereo 16bit 44k (don't know the frame rate)
converted it to an avi with asfTools which came out to 162 mb. Same frame rate and audio stats. The files look and sound identical when played.
Coverted it in TMPGEnc to MPEG-1. I reduced the suggested bit rate for the video from 1150 to 400. I changed the audio to 8 bit mono.
The completed file is 281 mb.
The video and audio look horrible compared to the original.

I know I'm doing something wrong and as I said in my post, I only converted to AVI to do some color editing. But that quest is what got me interested in why my files get bigger and bigger with each compression and the files look worse.

Even the first file I was posting about I converted to mpeg-2 for DVD and it was 11.5 GB. AND it doesn't even give me options to change the bit rate for video (using Vegas video).

[jimmalenko]

OK, you are starting to understand a few things.

ASF and WMV are very very good at compressing video. It is IMO the best when you still want reasonable quality but file size is paramount. As you have seen, MPEG-1 cannot compress as succesfully as these two. DivX and XviD lie somewhere in between the two. What format you choose really depends on what you want to do the finished product.

Do you want it on VCD/SVCD/DVD ?

Do you just want it on your computer ?