Digital cameras normally save the photos in file names such as DSC_0001 and it is impossible to determine what the photo is about unless you open and view it in a computer. Microsoft implemented a very useful feature called thumbnail previews since Windows XP where instead of showing a default icon for the file extension, it displays a thumbnail of the photo for a quick preview directly from the Windows Explorer without opening the photo. This allows the user to quickly search for the photos that they are looking for. The thumbnail preview also works for video files but unfortunately the support for videos is quite bad. Generating video preview thumbnails is much more sophisticated if compared with images.
First of all, there are many video formats today and Windows is only capable of displaying thumbnail preview for the limited videos that it supports. One of the most popular video format today is MKV which is the Matroska video format and Windows will either show a white color blank icon or the icon of the media player. Other than that, the first frame of the video is normally used as the thumbnail preview by Windows and to be honest, the first frame are usually black in color, the Dolby Digital intro or similar which will end up having identical thumbnails.
If you’re annoyed by the flawed video thumbnail preview in Windows, fortunately you can easily improve it by using a free configuration tool called Media Preview to display better and more relevant thumbnails for video files. Media Preview is able to help you generate thumbnails for a total of 37 different video extensions which includes the following video formats: 3G Partnership Project, Audio Video Interleaved, Flash Video, Matroska Video, MPEG-1/MPEG-2, MPEG-4 Part 14, MPEG Transport Stream, Ogg Video, Quicktime, RealMedia, Video Object and Windows Media.
After installation, all you need to do is run the Media Preview Configuration shortcut that is installed to your desktop, and tick the check boxes that you want it to generate the thumbnail preview from the File Format tabs. You can also define your own extensions and restore the media file association of the thumbnailing system to Windows default settings.
The Testing and Cache tab allows you to perform live testing to compare the thumbnail differences between the one that is generated by Windows and by Media Preview. Do note that Media Preview only generates the thumbnail of video files and it doesn’t automatically mean that you can play the video file if you can see the preview thumbnail. It does that by using Libavcodec.
You shouldn’t notice any slow down by using Media Preview to generate video thumbnail preview but if you do, you can simply set it to Speed instead of Quality by moving the slider from the Settings tab. At the Advanced tab, disabling Video Reel Image and File Type Icon overlay on thumbnails can also speed up the thumbnail generation.
Below is a short video demo on how I configure Media Preview to generate thumbnail preview for all MKV files.
Media Preview is free and works on Windows XP, Vista, 7, and 8. You will need to download and install the correct version of Media Preview depending on your Windows operating system which is either 32-bit or 64-bit.