Thumbnail image file (Microsoft Clip Gallery v.1.x)
THM is an image file format for thumbnails. Images are made smaller for browsing purposes, usually because it is easier to view and takes less time to load. THM files can be viewed by most image preview or editing programs on both Macs and PCs. THM files are similar to .JPEG files, and those .THM files representing image files can usually be converted to JPEG format by changing the name of the file from .THM to .JPEG or .JPG. THM files can also be used by videos. When extracting a video file from a camcorder, a thumbnail will be created to represent the video, usually taken from the video’s first frame. The .THM file will then have the same name as the .AVI file that it represents. With Canon-created video files, the .THM file also contains the metadata for the video, and therefore needs to remain with and have the same name as the .AVI file.
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