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Poll

Which one is your extension MP4 or M4a?

MP4
[ 93 ] (49.7%)
M4a
[ 94 ] (50.3%)

Total Members Voted: 258

Topic: MP4 or M4a (Read 26888 times) previous topic - next topic
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MP4 or M4a

Reply #25
Some filesystems can't support two dot (.) file extensions like .audio.mp4

Others operating systems still in use like DOS and it's derivatives can't support extensions properly longer than 3 letter extensions. So 3 letter file extensions are here to stay...

I think ISO set a standard for a 3 letter file extension long ago in the initial CD-ROM format . I am not sure what color book the spec was (something like red book, peach book, etc.). This was back in the late 80s/early 90s I believe.

MP4 or M4a

Reply #26
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Anyway extensions are a good idea because they maximize interoperability between OSes which is infinately more important/useful than worring about file system esthetics.

Well, I would say that extensions are a BAD idea that is unfortunately so widespread that you have no choice but to surrender to it in order to achieve interoperability.

Just because most people use it doesn't mean it's good.


MP4 or M4a

Reply #28
Thanks rjamorim for that! Yellow book it is...

I just remembered back to the late 70s, when I owned one of the early TRS-80 Model I 16K computers and I added the TRS-DOS disk operating system, the filenames had 3 letter extensions as well. In fact I just pulled this factoid up about TRS-DOS (circa ~1978):

In all the different TRSDOS type operating systems, there were several common features they all shared. Among these were: Disk drives were refered to as :0 to :3, file names were eight characters with an optional three character extension, the separator for the extension was a slash (/)

So it appears the 3 character file extension goes way back...

MP4 or M4a

Reply #29
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Quote
Anyway extensions are a good idea because they maximize interoperability between OSes which is infinately more important/useful than worring about file system esthetics.

Well, I would say that extensions are a BAD idea that is unfortunately so widespread that you have no choice but to surrender to it in order to achieve interoperability.

Just because most people use it doesn't mean it's good.

Conversely just because you don't find it elegant doesn't make it bad.  However the system works well, and theres nothing to prevent OSes from expanding it in their own proprietary ways so i see no problem with it.

Also i disagree that a metadata system would be better for interoperability.  It would be easily broken/made incompatable/extended by each vender.  too easily.  The fact that file extensions are so ridiculously simple is quite a virtue.  Anyone can understand them and they are virtually impossible to break or make incomptabale.

MP4 or M4a

Reply #30
Pardon me, what exactly is the advantage of storing the filetype metadata in some hidden place? It wouldn't help against a VBS virus, either. 

What, besides the specific implementation, is different from hiding the extension?

MP4 or M4a

Reply #31
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Quote
Is it wise to restrict oneself to audio and video? What about video+subtitles or audio+chapters or, uhm,  subtitles+chapters (is it even possible?)... 

The extension is .mkv

Well, for MPEG-4 I'd say it's MP4. I don't see any advantage in using Matroska if your file is otherwise standards compliant.

Quote
What about something like:
.audio.mp4
.video.mp4
or something similar?

Wouldn't most systems completely ignore anything prior to the extension? AFACT the main idea in using different extensions is to have the OS treat MPEG-4 audio and video like any other file...

MP4 or M4a

Reply #32
Some of you may remember the Apple II  DOS and ProDOS.

They both used the file type written alongside file size and date in the filesystem.

Having to use a block editor to modify a file type was awkward but it worked, many times I've appreciated the simplicity of using extensions, but not it's limitations.

And so the Mac inherited this method from it's older brother. 

MP4 or M4a

Reply #33
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Conversely just because you don't find it elegant doesn't make it bad.  However the system works well, and theres nothing to prevent OSes from expanding it in their own proprietary ways so i see no problem with it.

The current system allows you to accidentally wipe out the extension when renaming a file. In my opinion, that's a mistake. And hiding file extensions isn't a proper solution.

Take, for example, WinRAR: it sees .CAB .ARJ and .ACE files simply as "WinRAR archive". How are you supposed to distinguish one from the other if file extensions are hidden??

Sincerely, I don't understand how can you say that the current system "works well" 

Quote
Pardon me, what exactly is the advantage of storing the filetype metadata in some hidden place? It wouldn't help against a VBS virus, either


There's a VBS virus that tries to deceive the user by putting the ".mp3" extension just before the ".vbs" one. I've seen quite a lot of people who have been infected because they thought they were double-clicking an .mp3 song.

Cheers.

MP4 or M4a

Reply #34
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And hiding file extensions isn't a proper solution.

Take, for example, WinRAR: it sees .CAB .ARJ and .ACE files simply as "WinRAR archive". How are you supposed to distinguish one from the other if file extensions are hidden??

But that is WinRAR's fault, not the one of the system! What would hinder a program from screwing the metadata the same way in a Mac-environment?

I agree though, the conventions for naming file types in Windows should be better. (On the other hand, I never hide the extensions so I'm not really bothered.)

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It wouldn't help against a VBS virus, either

There's a VBS virus that tries to deceive the user by putting the ".mp3" extension just before the ".vbs" one. I've seen quite a lot of people who have been infected because they thought they were double-clicking an .mp3 song.

And they wouldn't click a file "new-cool-song (MP3)" with a music icon and a cryptic metatype (VBS)?

MP4 or M4a

Reply #35
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Is it wise to restrict oneself to audio and video? What about video+subtitles or audio+chapters or, uhm,  subtitles+chapters (is it even possible?)... 

hmm that would be a text book :-)
Sven Bent - Denmark

MP4 or M4a

Reply #36
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But that is WinRAR's fault, not the one of the system! What would hinder a program from screwing the metadata the same way in a Mac-environment?


Yes, I know it's WinRAR's fault. I was simply using that example (although there are many more, unfortunately) to point out that hiding extensions isn't the solution to the problem.

Quote
And they wouldn't click a file "new-cool-song (MP3)" with a music icon and a cryptic metatype (VBS)?


Well, perhaps. But maybe users wouldn't be so confused as they are right now when they see that some systems hide file extensions and some others don't. In fact, you have just admitted that you deliberately unhide file extensions.

Wouldn't you like better a system where there's no need to hide anything?

And why are file extensions hidden in the first place? Because they can easily be accidentally renamed by novice users. File extensions are just an ugly hack to a problem. And filetype metadata would have been a better solution.

Cheers.

MP4 or M4a

Reply #37
Continuum, id3 tags are type of "hidden" metadata. Would you prefer that all the id3 data go into the filename?

MP4 or M4a

Reply #38
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Wouldn't you like better a system where there's no need to hide anything?

I always thought, that metadata implementations are even more prone to hiding. How easily can you change the meta-filetype? That's one reason, why I like extensions.

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id3 tags are type of "hidden" metadata. Would you prefer that all the id3 data go into the filename?

Practical reasons forbid that. But then, if the tags are only part of the metadata (not the data itself, like it is now), they could easily be lost during a file transfer.

There is no general (OS independent) description tag with files, the only consensus is filename and date.


Anyway, that's not my point. The question was, if there had to be a practical difference between hidden extensions and metadata. I would think, that an OS could interprete file extensions as metatype and look like a native metatype implementation to the user.

MP4 or M4a

Reply #39
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There is no general (OS independent) description tag with files, the only consensus is filename and date.

But there is, even if it's not always used. A simple graphic file has a tag some examples GIF89a for GIF, JFIF for Jpeg, BM6 for BMP and audio RIFF for WAV etc.

If the program's parser intelligently identify the file by it's content and not by it's extension there'll be no problem reading the file.

MP4 or M4a

Reply #40
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If the program's parser intelligently identify the file by it's content and not by it's extension there'll be no problem reading the file.

Deciding the file type based on the contents of the file is not something you'd want your OS to do. There's too much that could go wrong...

MP4 or M4a

Reply #41
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But there is, even if it's not always used. A simple graphic file has a tag some examples GIF89a for GIF, JFIF for Jpeg, BM6 for BMP and audio RIFF for WAV etc.

This is not at the file system level! For the OS this is just data (although it's "metadata" from the user's point of view). See my argument against ID3 above.

MP4 or M4a

Reply #42
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This is not at the file system level! For the OS this is just data (although it's "metadata" from the user's point of view). See my argument against ID3 above.

The problem with attaching metainformation to a file is that it alters the entire concept of a file. On almost all systems, a file is a stream of bytes, the contents of which does not matter to the system. This means that by reading a file from the beginning to the end, you have an exact representation of the file.

The only system I know of which broke this model is the old model used in the old Mac OS. It was abandoned because it does not mesh well with the UNIX file model and causes all sorts of other problems - files must be archived when sent, etc. Any new file model should at least be kept backwards compatible with the traditional file representation.

MP4 or M4a

Reply #43
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This is not at the file system level! For the OS this is just data (although it's "metadata" from the user's point of view). See my argument against ID3 above.

The problem with attaching metainformation to a file is that it alters the entire concept of a file. On almost all systems, a file is a stream of bytes, the contents of which does not matter to the system. This means that by reading a file from the beginning to the end, you have an exact representation of the file.

The only system I know of which broke this model is the old model used in the old Mac OS. It was abandoned because it does not mesh well with the UNIX file model and causes all sorts of other problems - files must be archived when sent, etc. Any new file model should at least be kept backwards compatible with the traditional file representation.

MP4 or M4a

Reply #44
I think Apple should be Spanked over this one, everyone knows .mp3 is audio, so .mp4 should also be audio - also audio files will out number video files by a large number it should have the 'better' extension - put video as .m4v

MP4 or M4a

Reply #45
i dont see a problem in using .mp4 for both audio and audio+video i just need an oggprak-like tool 
I know, that I know nothing (Socrates)

MP4 or M4a

Reply #46
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i dont see a problem in using .mp4 for both audio and audio+video i just need an oggprak-like tool 

You and everybody else. I don't think that's a very sensible option.

MP4 or M4a

Reply #47
or simply one player that handles both audio and video in a nice and usable way
I know, that I know nothing (Socrates)

MP4 or M4a

Reply #48
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I always thought, that metadata implementations are even more prone to hiding. How easily can you change the meta-filetype? That's one reason, why I like extensions.

The OS could include a little command-line utility to change the filetype metadata to whichever value the user wants to set.

Or you could always download a freeware utility to do just that. I'm sure somebody would make one freely available before long.

Then again, may I ask you how do you change the "last-modified" and "created" timestamps of a file? Those can't be changed at will by the user so easily.

Would you favour having timestamp metadata also appended to the end of the file name as well?

I think you are sacrificing a clean design in order to achieve "laziness" (I mean, come on, using a command line tool isn't that difficult!)

Cheers.

MP4 or M4a

Reply #49
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or simply one player that handles both audio and video in a nice and usable way

And expect every single user to switch to that player? Yeah, sure...