VirtualDub has the ability to split videos or trim a portion of a video file with the position slider. To do this:
1. Go to the Video Menu and check the "Direct stream copy" option. Then go to the Audio Menu and do the same.
2. Use the "Edit" > "Set selection start" and "Edit" > "Set selection end" commands to select a portion of video. This can also be done through the mark-in and mark-out buttons below the position slider or through the Home and End keys on the keyboard. Then the currently selected part will now turn blue at the slider.
3. After that, click the "File" > "Save as AVI" menu command to save the AVI segment.