If "1545.mp4" is showing an error (like "format not supported"):
: Use MediaInfo for a deep dive into the specific codecs used, which is helpful if a standard player like QuickTime or Windows Media Player fails. 2. Common Fixes for Playback Issues
If the file won't play or you need to know its origin, you can check its metadata:
: Select the file in Finder and press Command + I (Get Info) to view the "More Info" section.
Based on common file naming conventions, is likely a video file where the "1545" prefix refers to a specific timestamp (3:45 PM), an ID number from a camera/recording device, or a part of a sequential batch.
: Many systems name files by the time of day (e.g., 15:45 or 3:45 PM).
: Download VLC Media Player —it includes built-in codecs for almost every type of MP4 file.