The most popular video format in today’s date is MP4 as it is supported in all the devices and platforms. Besides MP4 format often uses codecs with a very good balance of quality and file size – so that you get a small size video file while getting a very good quality of the video.
These video formats contain a special data unit called moov atom that contains very important information about the video itself like the number of video frames, number of video/audio streams, timescale and duration of the movie and so on. This information is added by the video recording device once the video recording is complete. But if your device abruptly shuts down in the middle of recording something, then this information is not included making the whole video file useless. But you can still fix the video file using a simple video repair tool.
In the Video Repair tool, you have to select a source file (the video file that you want to repair) and optionally have to select a reference file (a file very similar to the source file) and then click on the Scan button. It will go through your video file and find out whether it can be repaired or not. It should be able to extract the video and audio streams in separate files. Now you can click on these extracted streams and watch a preview. If the preview is visible/audible then the video file can be repaired. At this point, you can click on the Repair button to proceed with the repair and saving the repaired video file. The fixed or repaired video files are saved in a sub-folder named repaired.
However, there are limitations in the Video Repair tool. For example, you cannot fix all kinds of video files. It can fix only some files created using a number of video devices (listed on the developer’s website). And in the demo mode, it repairs only 50% of the total length of the video.
You can download Grau’s Video Repair Tool from http://grauonline.de/cms2/?page_id=5.