I recently downloaded a DivX (3.11) movie file from the internet. After scanning the file with VDub Mp3 I discovered that it had many bad frames in the middle of the movie. Nearly 10 crucial seconds of the movie would have been lost if I deleted the bad frames.

So I decided to download the same movie a second time. The second time I still had just as many bad frames, but in a different location.

A simple solution, it seemed, would be to delete the bad frames from the first movie file and replace them with good frames from the second movie file. This would ensure good quality and playability, while preserving the file's (and most importantly the movie's) integrity.

So I used Virtual Dub Mp3 to save the following new DivX movie files (3 in total):

1.) The beginning of the movie to the point where the bad frames began.

2.) The "GOOD" frames from the second downloaded movie where the bad frames existed in the first downloaded movie.

3.) The point where the bad frames ended to the end of the movie.

I then joined the three files together and saved the final movie as one relatively perfect and flawless DivX file. It plays wonderfully! I used Direct Stream Copy for both the audio and the video in the saving of this file as well as the previous three.

To my surprise the final movie is slightly larger than the original source files. The final new movie and the original source movies have the same number of frames - hence they should be the same size. Is this extra data added by Virtual Dub Mp3, or am I not getting an exact copy of the original source material? And is there a way to make it the same size as the original? Thanks.

(Interesting enough, in the file information provided by VDub Mp3 I noticed a change in the Preload skew category from 5,500 samples to 5,991 samples - does that mean anything?)