The best tool to split, trim or join WMV / ASF files
Pros & Cons:
AsfBinWin, the graphical user interface version of the AsfBin command line utility plus preview capabilities, is a clear winner in this category. This lightweight portable is free for non-commercial use and will cut or join wmv files very well. Better still, it can often fix and re-index wmv files that are corrupt or contain some errors.
The controls are both sensitive and user friendly: there's a primary slider to take you to roughly where you want to cut, and then a second slider allows fine tuning down to a single frame. Indeed, the ability of AsfBinWin to re-encode locally makes precision cutting possible—so you can cut the video exactly where you need to.
Although the developer's website does not specifically mention trimming, you can actually do this: just select the section(s) you want to cut away, click the "Insert" button, followed by "Invert Ranges", and then press "Cut/Copy/Join". For splitting, don't forget to click "Preview" for the preview window, and "Save each segment to a separate file". Older computers may require installation of MFC 9.0 libraries (download from here).
In addition to wmv and asf video files, this handy little portable can also cut, merge, trim and fix wma (audio) files. AsfBinWin can normally handle any video file encoded in wmv3, mp42 and mp43 video formats with precise cutting enabled (the default setting). However, if you want to use this utility for other formats, you might find you have to disable precise cutting in the Advanced Settings to avoid a scrambled result. But overall, AsfBinWin is a remarkably reliable and efficient little package which does what it just about says on the tin.
AsfBinWin was reviewed by Gizmos Freeware on