For Mac, the MetaX is discontinued, but you can use an updated version called MetaZ. MetaX has lots of settings that allow you to use it in the way you like. It supports to import the tag info from, TVDB, IMDB, iTunes for MP4, M4V, WMV, AVI and MOV files automatically or you can type the info manually.

Top Video Metadata Editors Recommended MetaX How Can You Edit the Metadata of iTunes Videos

But if you don't have the project anymore, you can try to edit M4V medatadata directly by using the following metadata tools. There is an option to change the info on the pop up dialogue window. Regarding to the issue mentioned above, if you still have the project file on FCP, you can try once again to export the video. It usually consists of title, movie release date, actors, director, producer, genre, rating, thumbnail, chapter. Metadata, also known as data about content, is the supplement info stored on the movie file. Is there a way to modify or remove the metadata from M4V files?' - Question from Apple community. The video works well but it combines some wrong metadata such as my computer name, software info. ' So here is my problem: I created an M4V video with Final Cut Pro on my Mac and play it through my Plex.

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