Adding thumbnails to multiple files

[VladoBENZ]

Hello, I have a question. For example I have 20 files named DSC0001.jpg, DSC0002.jpg etc. And I prepared 20 thumbnails, named DSC0001.jpeg, DSC0002.jpeg etc. in the same folder. Is there any way with one command to insert the corresponding thumbnail in all the images, because if I use a command for every file...basically I have 300 pics in the folder lol.

[StarGeek]

See this example from the docs.

The command is basically the same, except you want to ThumbnailImage instead of JpgFromRaw and alter the filename part to reflect your filenames.  The -r (recurse) option can be removed if all 300 files are in the same directory.  Also, you want to make sure and use the -ext (extension) option to work on just the .jpg and not the .jpeg files

exiftool '-ThumbnailImage<=%d%f.jpeg' -ext jpg <DIR>