image to jpeg conversion can actually mean hundreds of different graphics exports and should be searched with specific file format in mind, for example gif to jpg.
Said that, you can find actual .image files that is files that have the image file extension, but these are incredibly are and often have just their original extension renamed.
You can always try to open your .image file using standard graphics editor, chances are hight that this will work and you can resave the files to any format available.
Updated: November 1, 2023