What you mean? You mean to translate subtitles or you want to translate sound? Could you give little more info about what you want to achieve (what is input and how you would like to have output look like)?
If you want text translation you can try numerous starting with google translate to some paid translators. You can google quite many. But don't expect miracles it may give you some global idea about what is translated but more complex sentences may be hard to translate. Also Japanese is strongly contextual language so one sentence can be tied to previous making mess with translators.
Just put it to google and you will get many results, you can try them one by one to see which give you best results.
If you mean to translate sound I'm afraid you are out of luck. Sure you can try to find some translation programs but they will work even worse than text translates.
Sorry but voice to voice translation is still too hard. There are some limited possibilities to translate using voice, but no chance for full contextual translation on scale of whole movie. Software like that would make one who make it billions .
If you are talking about some japanese movies or anime, rather try to get english subtitles. No translation can beat original japanese voice cover of movie/anime and very few come close. Added value is that you can learn few phrases in process if you are interested.
If you really want something like that try to search at net you may find some software, but on 99% it will be paid and it will have limited possibilities. I found some info about domain oriented translations for business.
Another option if you won't find some direct speech to speech you can try speech to text (jap voice - jap text), translator and (eng text to eng voice).
BUT translations like that will have tons of error and unless you understand both languages you won't be able to correct them and you will end with one semi mechanical voice cover of video.
In short what you want is possible in very limited ways and it will cost you and I'm sure you won't get what you really were looking for.