A THM file is a Thumbnail image automatically created from the first frame of a video file on digital camcorders, cameras, and smartphones. It is generated when a video file is saved by the device camera. The thumbnail preview images from all the videos are displayed to the user for choosing the video of interest from the videos collection. THM files are saved in compressed binary format in memory to reduce space utilization. THM files can be opened with applications such as Apple Preview and Adobe Photoshop 2022.
THM File Format - More Information
THM files are raster images saved to disc in binary file format. The main purpose of THM files is the identification of the video file by its thumbnail image. In most cases, THM files have the same name as the corresponding video file name. For example, a video file having name MOV001.mov will have MOV001.THM as its thumbnail file name. THM files extension can be renamed to JPEG to open them if they don’t open directly by double clicking.
Is it OK to delete THM files?
THM files are thumbnail images for the videos recorded by camcorders. Deleting these won’t have any effect as the original video remains preserved.