Reducing the size of an avi file

[dipdog]

I've been playing avi files on my laptop, but I found out that it unfortunately has a fixed 8mb GPU which can't be upgraded (Dell Latitude c600), so files which have a data rate or frame rate that is too high end up playing back choppy. I was just wondering if there is a way to directly reduce the frame rate or data rate on an existing avi file?

Thanx
- Scott

[Terranigma]

1. Virtualdub - Video - Frame Rate... (Change the fps here)
2. Video - Direct Stream Copy - File - Save as AVI... (This will do a direct copy of your avi file with the fps you desire)

I'm assuming you're talking about the fps since you've mentioned framerate.

[setarip_old]

@dipdog

Hi!

Have you tried simply selecting a lower color depth setting and/or reducing the desktop resolution to either 640x480 or 800x600?

[CWR03]

I was just wondering if there is a way to directly reduce the frame rate or data rate on an existing avi file?
You would need to re-encode the file to a lower bitrate. Framerate is not the issue, nor would be the color depth setting or desktop resolution.

[The Scientist]

Yes changing the FPS may not be such a good idea......

CWR03 is right, re-encoding may be your only answer but first, what is the current bitrate, dimensions, codec, audio bitrate and type of the AVI/s in question?

What player are you using to view them? A simple change of player could do the trick.

Give some more info.

[dipdog]

Whoops, sorry it took so long to follow up on this. I must have forgotten to select email notification.

I'm not much of an avi expert, so I was mostly guessing at this. But I have movie files that are larger (<1GB) and files that are smaller (around 600-800 Mg) and I noticed that the larger files are choppy during playback, so I assumed that it was somehow related to file size. When I looked at the properties, the main differences that I noticed were the frame rate and data rate, so I assumed that those might account for the differences in file size and playback. When I play the larger files with Winamp, the video plays back choppy, not smooth (like an old-fashioned movie). When I play them with WMP, the video plays back smoother but the audio gradually goes out of the sync with the video, and then catches up again every few minutes.

The frame rate of larger movie files is 29f/s, while the frame rate of smaller movie files is around 23f/s. The data rate of larger files is around 150-180kbps, while the data rate of smaller files is around 100-120kbps. They're all pretty much XVID with video sample size that varies from 12 bit to 24 bit, audio bit rate that varies from 100kbps - 200kbps, and dimensions that vary from 400-500 x 600-700. I'm playing them back over a wireless connection on a laptop from a PC harddrive. I considered that it might be the wireless transfer, but the larger files play back choppy when I copy them directly to the laptop HD as well.

I tried changing the frame rate with virtualdub, from 29 to 23, but it didn't seem to make much of a difference in file size or playback. I'm sure this is an ignorant question, but if the bitrate does need to be changed, by that do you mean the audio bit rate, the video sample size, or the video data rate. Can that be done with virtualdub. If so, is there any chance you could mention how (is it done through video>compression?).

Also, this is sort of a separate subject, but can you merge avi files with virtualdub?

Thanx for all your help!

- scott

[Mtz]

Merge files with "Append Segment". If you have a choppy playback I think the issue is the bitrate. You can easy reencode the larger files with AutoGK just choosing the output size. Smaller size = smaller bitrate.
Before all this things try also another players like Media Player Classic or VLC. You can also try to use another decoder like ffdshow and make some settings in the Decoder Configuration for a better playback.

enjoy,
Mtz

[setarip_old]

@dipdog

As yet, have you tried simply selecting a lower color depth setting and/or reducing the desktop resolution to either 640x480 or 800x600?

[dipdog]

Setarip_old - Sorry, yes I did. Didn't improve the situation much, if any.

MTZ - Thanx. I'll try AutoGK. I have a copy but I haven't used it before. Is it pretty self-explanatory?

Also, what is VLC. Does ffdshow work with any player? How do you chose a decoder to work with your player. And what decoder configuration changes should be made? (sorry for all the questions. :)

Thanx for your help!

[dipdog]

Just a wanted to leave a quick followup for the thread. I tried Windows Media Player Classic, and it worked great. No longer choppy, and audio plays smoothly with even the largest files.
Also, tried "Append Segment" with VirtualDub, and it worked great.

Thanx again for your help!

- Scott

[Blue_MiSfit]

Glad to hear it! Media Player Classic is a great DirectShow player, and if you need something very lightweight, MPlayer is a great choice too!