MediaInfo

If you don't know any details about a media file you are playing or more importantly, about a file you can't play, you can use MediaInfo to retrieve all the information you need. Besides telling you about a media file's format, codec IDs and other details, the application can also tell you where to get the necessary codecs for playing that file. It is offered free of charge, for various operating systems and it doesn't take more than a minute to install it.

All you have to do is load one or more media files on the application's compact user interface and their metadata will show up instantly. You can use separate options to load individual files or entire folders. By default, the application will display information for each file separately, leaving you to select different files in a drop menu. Alternatively, you can choose a different view mode, like HTML or plain text, in which the application will display information for all loaded files on a single page.

Once you load a file, you will find general information, like format, duration and so on, as well as information about the file's video and audio codecs. What's more, MediaInfo provides Search options for those codecs. If you don't have them installed on your Mac, you only need to click these buttons and the application will take you to their download pages immediately.