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Does Windows- 7 already have something that would convert .m4v to .mp4?

If not, how would I do that?

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up vote 13 down vote accepted

In most cases, it's easy enough to just rename your file from .m4v to .mp4. There is no conversion needed.

Both .m4v and .mp4 can be used as extensions for the MPEG-4 Part 14 container format. While .m4v isn't used that often, .m4a is common for audio-only files.

There are two cases in which renaming does not work:

  1. Sometimes, .m4v is also used as an extension for raw MPEG-4 Part 2 video bitstreams. In this case, renaming is not possible. The file has to be multiplexed into an .mp4 container instead. This can be done, for example, with ffmpeg: ffmpeg -i input.m4v -c copy output.mp4

  2. When they originate from iTunes, .m4v files may be protected by Apple's DRM. In this case, renaming to .mp4 is not possible, and you cannot convert the file itself either, as it is copyright-protected and can only be played with iTunes on the machine it was bought on.

In either case, it is not necessary to convert the file by re-encoding it. This would only deteriorate the video quality. It is certainly not necessary to buy some kind of video conversion software for this task either.

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Indeed. The “v” is for video. It’s basically information just for humans. There’s also m4a for audio. – Daniel B Jul 5 '14 at 14:16
Yeah, typically you would name audio-only files .m4a. The iPhone uses .m4r for ringtones, for example. – slhck Jul 5 '14 at 14:17
I would add that extensions don't change the file, just how the computer decides to use it. – fredsbend Jul 5 '14 at 17:26
Mostly not even that. Because the file name is not truly metadata, it cannot be relied on. Instead, the presence of well-known/well-formed data is tested. – Daniel B Jul 5 '14 at 18:29
For those looking for useful information: m4v and mp4 are not necessarily the same thing at all: an m4v file can be a pure data stream for burning directly to disc, without any metadata. In such cases, the file needs to be packed in an mp4 container before it can be played as file in a software video player. Even in 2016, this affects people why use, for instance, Adobe Media Encoder. – Mike 'Pomax' Kamermans May 9 at 5:59

Leawo total media converter, or maybe AVS Video converter
They are both paid, but have free versions

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I downvoted because there is no need to convert anything in the file. In fact, using such a conversion tool you mention would only deteriorate the quality of the contained audio/video by re-encoding it. (Good example of generation loss) – slhck Jul 5 '14 at 14:18
Very true, free trials usually have their limitations. But I do not appear to have a downvote.. ? – Micheal K Jul 5 '14 at 14:21
That's not a matter of free trial vs. totally free or super expensive. You do not need a conversion program. Quite the contrary: you should avoid it, because they unnecessarily re-encode the audio and video parts (unless you know and find the option that does a stream copy, but not every tool has this). You received one upvoted, hence the 0 score. – slhck Jul 5 '14 at 14:22
Ah, Thank-you sir. I have become so used to converting all my videos that I kind of jumped the gun. Learn something new everyday, I guess. – Micheal K Jul 5 '14 at 14:35
Downvoted because this doesn't actually explain why...with an explanation the OP would realise there is no need for an external program. – JB_STWUK Jul 5 '14 at 21:13

You can check this convertor out WinxHD, it's not free but you can easily work your way round and it facilitates m4v to mp4 or vice versa.

Hope I helped.

Enjoy :)

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Can anyone tell me why is my answer downvoted!? – Naveen Niraula Apr 17 '15 at 11:33
There is no need to convert anything at all (see above answer), and even more so, it's not worth paying for video conversion tools either when there are free alternatives. – slhck May 10 at 11:27

protected by Community Sep 7 '14 at 7:19

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