What is a nar file

Like the original poster said in a comment, the information on FileInfo hasn't been updated to take Windows Phone cameras into consideration.

.nar: Like Thomas answered, the *.nar files are basically renamed *.zip files that include extra pictures, photo data, etc, and are related to Lumia Refocus and Rich Capture.

.thm and .tnl: These two files are related to the Living Image feature. If you set file extensions to be visible, you'll notice that Living Images always come in a trio of files when working properly:

  • WP_datestamp_Pro.jpg: This is of course the actual picture.
  • WP_datestamp_Pro.mp4.thm: Notice the extra .mp4 in the file name. This is the actual living image, and is packaged as an .mp4 with an added file extension to differentiate from the videos that your camera takes.
  • WP_datestamp_Pro.mp4.tnl: This is, as noted above, the thumbnail for your Living Image video. This will also appear for actual videos that you take with the normal .mp4 extension. Occasionally, you'll see a .jpg with an associated .tnl but no .thm, meaning the Living Images messed up and never recorded a video; I personally delete those, as they are unnecessary.

If your phone saves in higher resolutions and your settings allow it, there will be a fourth file:

  • WP_datestamp_Pro_highres.jpg: This is the full resolution picture. For example, if the settings are set to capture JPEG (5MP + 16MP), the first .jpg will be 5MP and the highres.jpg will be 16MP.

Also note, with Windows 10, the format has changed a bit. Living Images are now embedded in the .jpg instead of a separate file, though I can't quite explain as I haven't had much experience with them.

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