Greetings. I have not seen this exact topic discussed before, although a poll was taken to see which of the 2 MPEG 4 Audio file extensions people preferred as their "favorite".

The poll is at: http://www.hydrogenaudio.org/forums/index....howtopic=17340&

As I am writing this, people here on HA were almost 50/50 split as to which file extension was better (M4A or MP4) for naming MPEG 4 Audio files. This implies to me that we are woefully undecided about a "favorite" or preferred file extension for MP4 Audio files. Having half the audio apps using one and the other half using the other file extension is not good.

This is not only confusing to us, but think about the confusion that having 2 different file extensions has/will introduce to the average consumer trying to encode or playback MPEG 4 Audio files. They will likely ask questions such as: Which file extension should I use? Is one better than the other, what's the difference, etc?

I am in the process of compiling a MPEG 4 Audio FAQ to better help new users to MPEG 4 Audio. I get many requests daily from users on the web searching for the difference between .m4a files and .mp4 files, etc. The reason I wanted to write this is to avoid the compatability questions and mis-conception between users of .M4A and .MP4 files. As most of us know here on HA, the files are exactly the same and can be renamed from .m4a to .mp4 at will.

Only the existance of the dual file extensions is causing a "stumbling block" among users and between different audio software programs (i.e. some programs use one file extension, other programs use the other file extension).

I think we need a "universal standard" which all software developers will voluntary agree to implement so as to avoid the potential conflicts and frustration their users may have between properly reading and encoding MPEG 4 Audio files.

As we know:

M4A represents MPEG 4 Audio (non-DRM, i.e. unprotected)
MP4 can represent MPEG 4 video only, both MPEG 4 Audo and Video combined in one file or MPEG 4 Audio.

Hence the liklihood for confusions, as .MP4 is a "catch-all" file extension which may or may not cause various software apps headaches in determining what type of content is included in the MPEG 4 container file. Some audio apps won't playback .mp4 files assuming they are video files as an example.

The only way to know for sure that an MPEG 4 container file contains MPEG 4 Audio only is to use the M4A file extension.

Since there now exists out there ("in the wild") a hodgepodge of different audio apps each supporting a different file extension (MP4 or M4A), I propose we solve this problem and enhance overall compatibility for all apps and end-users alike by following the following 3 simple steps:

1. Have all MPEG 4 Audio players support the reading (decoding) of BOTH .M4A and .MP4 files (currently many support only one of the two file extensions)

2. For all software apps, that offer a 'Save As' or 'Encoding' feature, have it so that the software apps will support saving with EITHER a M4A or MP4 file extension (some apps hard code file extensions for saving to MP4 or M4A only currently).

3. In addition to the above #2 of support saving/encoding using EITHER the M4A or MP4 file extension, allow the user (via a method like a check box option/setting or a pull downfile extension preference) to select THEIR preferred MPEG 4 Audio default file extension that will be used each time they save/encode unless they choose to override that setting.

(While we're at it, let's put all file extensions is lower case be default... There's nothing worse than getting a file with a lower case filename but a yucky upper case .MP4 or .M4A file extension appended/tacked onto it).

The above guidelines will help all players and encoder apps to get "better along" with each other which should boost the end-user experience with MPEG 4 Audio files and the apps in general, not to mention the likely reduction in tech support calls and E-mails from end users.

If software developers would incorporate the above 3 design functions in their audio apps, we would avoid the squabbling over which file extension is best (see the poll to see an example of this kind of discussion). Since no one is going to get everyone to agree on which of the 2 file extensions is best to use (.M4A or .MP4) and since the "cat is out of the bag" anyway and we can't change the many millions (?) of existing .M4A and .MP4 files that people already are using out there currently, we should just (for compatibility sake) support BOTH file extensions.

After all both .M4A and .MP4 are the SAME file format, just with different file extension naming... To quote Rodney King: "Can't we all just get along..."

Your comments are welcome and appreciated. It would be nice to see all popular MPEG 4 Audio supporting apps apply these suggestions to improve overall compatability between apps.

Here are the current defaults (or fixed file extensions used by popular softwware encoding apps):

Apple iTunes: default is .m4a for encoding and playback
WinAmp 5.02: can playback either m4a or mp4, encodes/rips to m4a
Nero 6: can read/decode either m4a or mp4 (with latest update), but can save to .mp4 extension only (appears to be hard coded)
Compaact: encodes to mp4 file extension only
Real Player 10 beta: currently plays back .m4a files only via Quicktime (can't handle .mp4 files as it thinks they are video files)
FAAD: can playback either m4a or mp4 in its various incarnations (WinAmp plugin, standalone decoder, etc.)
FAAC: depends on implementation

It appears that since Apple iTunes and WinAmp default to saving to .m4a, that this should likely be the default used for the reasons mentioned above as to avoid confusion with the growing number of MPEG 4 Video files that will be emerging soon that share using the .mp4 file extension also. But having apps be able to read/write to BOTH formats is the best solution for overall compatability's sake.

the mpeg-4 standard only offers one extension and thats .mp4

every developer who wants to follow the mpeg-4 standard and wants to use the mp4 container should support .mp4 input and output imo, simple as that

if some developer wants to support .m4a too, its a nice addon and noone will stop him, but .mp4 is mandatory imo,
as its the extension of the mpeg-4 standard, no matter if there is audio-only, video-only, rich-media-only or a mixture of those
(imagine we could also have different extensions for mp4 files which contain aac or mp3 in mp4, not to forget about h.264 and also maybe other extensions for asp and sp video files (i am sure most of you know that most hardware players still cant handle asp features like qpel and gmc) aso...)

imo instead of this whole extension mess, which hurts mp4 more than it does any good, i would be very glad if someone could write a small header-analysing tool, which passes audio-only files to an audio player and video files to a video player, like it is already possible with multimedia .ogg files with the great oggprak tool


and dont underestimate the amount of people who are using only 1 player, for both audio-only and audio+video files!

bond,

While I appreciate your comments, I think you are preaching to the choir. You can't put the M4A file extension back into the bottle. Apple started this widespread M4A file extension use, and it has become quite popular and many would say it is a "standard". It started with iTunes and iPod users and now has spread to many other audio apps that want to be iTunes/iPod compatible.

I did not post this to start a debate if M4A was a legitimate file extension or not, as it is already recognized by many file extension resources/dictionaries as legit:

http://filext.com/detaillist.php?extdetail=m4a
http://en.wikipedia.org/wiki/M4a

I merely wanted to propose a solutions to the already fragmented M4A/MP4 situation that exists currently out there between various audio players and apps. All I want is for every app to support reading and encoding to BOTH file extensions (user selectable).

Let the user select if they want a file to have a .m4a or mp4 file extension. Currently very few software encoders permit the user to select if they want a .m4a or .mp4 file extension saved on the file. Most hard code either a .m4a (iTunes and WinAmp) or .mp4 (Nero, Compaact, Fraunhofer) file extension onto the filename without allowing the user to change it at the time the Saving/Encoding is done. This is what frustrates most users I believe.

These both are the SAME file format, with just 2 different file extension names after all. This naming "boondogle" of having 2 different file extension names for the same thing is the cause for all this mess and confusion among end-users. I am just proposing a way to help "clean it up" and make life easier/more compatible for everyone now.

i of course didnt say that m4a shouldnt be used, i only said that .mp4 should be offered in any way to the users, as thats the extension which is standardised in the mpeg-4 standard!

i dont like the situation where one tool only outputs the private .m4a, but other tools (which are correctly following 100% the mpeg-4 standard) require .mp4 input...

following the mpeg-4 standard is the only real consensus which can be reached in this business to get 100% interoperability
everything else is a private addon, which will never be supported by 100% (even if you start this nice attempt) and which doesnt insure this needed interoperability the standard provides

guest0101: you don't happen to own m4a.com do you?

Thanks for you input. Well if it is true (and I don't have the MPEG specs so I can't personally verify this) thet the standard calls for only one file extension (.mp4), I wonder why Apple went with .M4A? Isn't there a mechanism in MPEG 4 that allows for additional file formats and extensions to be specified?

Anyway, we all know that .M4A can't be put back "in the bottle". Apple reports that over 2 million iPods have been sold, millions of copies of iTunes and over 40 million songs have been downloaded as of early January. Now with the Perpsi/iTunes 100 million song promotion and the HP announcement to put a copy of iTunes in every consumer PC that HP ships, this will make so many people using iTunes/iPods that .M4A support is a must for all software audio apps.

Many "average joe" users don't know how to rename files to get them to work in a different favorite encoder or player. As I said in my post, I get literally 100+ people a day coming to my site searching for information on how to either use, encode or convert m4a and/or mp4 files.

They are very confused. I think having 2 file extensions for the same container file format is bad, as it is causing much confusion out there among users.

The only solutions I know of (now that there are both .m4a and .mp4 files floating around out there), is to have all apps support both for compatibility sake. I am sure Nero's tech support in the past has been flooded with people asking questions related to this .m4a and .mp4 filename compatibility/usability issue. Thankfully Nero just added support for reading/decoding .m4a files in their latest update.

This issue will likely never go away, but instead we are faced with 2 different file extensions that will be used for years to come by people for MPEG 4 Audio files.

*cough* *cough*

JohnV,

Yes I do own M4A.COM as I have previously stated that in another thread here on HA, so I have not been hiding that from anybody. I have yet to develop the site, but plan on writing a MPEG 4 Audio FAQ and have an informational site.

I get almost 400 unique people a day on average to the M4A.com site (of which 100+ a day come from search engines searching with keywords such as: m4a, what is m4a, m4a to mp4, convert m4a, etc.)

But my frustration (and reason for starting this thread) is the inconsistant handling of the file extensions for MPEG 4 Audio files by various software apps (encoders and decoders).

I didn't invent .M4A (I guess Apple did), but since its use is so widespread out there (thanks mostly to iTunes/iPods), other audio software apps should support the reading and saving to that file extension in my opinion.

There is nothing worse than half the apps supporting only 1 file extension, and the rest supporting only the other file extension.

That is my real beef, and why I want to see both supported with the option for each user to select their preferred file extension in their apps when they save a file. Apple iTunes/iPod users have been for too long forced to rename their .mp4 files to .m4a for optimum use in their iTunes and iPods. Same goes for Nero users who have files encoded by iTunes or WinAmp that previously had to rename them (now fixed and hats off to Menno/Ivan for doing that in the newest update).

The average user (like many of the ones who come to my web site) doesn't know how to rename files, and software developers should accomodate them by allowing them to choose to save using .m4a OR .mp4 file extensions in my opinion.

Apple are AFAICT not violating any standards, and have no reason to move away from the M4A extension. Thus, if you want the entire world to use one extension for MPEG-4 audio, it's probably easier to make the rest move to M4A than make Apple abandon it. I'm not saying that's what should happen, but if Nero truly doesn't support the M4A extension, that would seem a bit silly to me...

to be able to play audio-only files in itunes and video files in quicktime... (i dont suspect apple having in mind to exclude competitor products which encode correctly to .mp4)

at first sight this may sound good, but altough renaming is not a big thing for many users maybe, it is hurting interoperability a lot


either way i dont think we will change anything in this development

Seems to me Apple is being a little slow on supporting the mp4 standard

Although there is an advantage to the Apple way IF video files start appearing en-mass as .mp4 rather than .m4v, because you might not want your Audio Player starting when a .mp4 video file is double clicked.

Actually, they already do, and such files are fairly common on the mac scene. QuickTime exports to MPEG-4 and uses the MP4 extension for them.

Note that using M4V for MP4 files is even sillier than using M4A given less players support it. Isn't it mainly used for raw, uncontained MPEG-4 video anyway?

Aren't file name extensions great!

I think guest has come up with a useable solution for the short term.

Thanks negritot for your positive comments about my solution.

After all, we're not talking about the VHS vs. Betamax format wars or anything. BOTH m4a and mp4 are THE SAME FILE FORMAT. This thing is just over a naming convention for the filename extension... No big deal IMO, but this naming issue is an annoyance to experienced users and seems to be causing confusion to many novice users.

Since we can't undo what has already be done, hopefully the developers of our favorite software apps will cause them all to play well togther by supporting both filename extensions and allowing users to choose which one they want to use

Life already has enough hassles without the need to squabble over or get heartburn from the naming of the file extension we use for MPEG 4 Audio files... I believe both M4A and MP4 are here to stay.

Thanks go out to Alexander at Compaact who contacted me a few moments ago saying he will try to include this feature in the next version of Compaact. This feature will add the ability to give users the choice of which filename extension (.m4a or .mp4) they want to use when they save/encode files using Compaact.

I appreciate the willingness of developers to make changes based on the suggestions from users. Most of them surely realize that the more users they support with their products, the higher the liklihood of their product's sales increasing.

Thanks to Menno/Ivan at Nero for recently implementing the ability to read .m4a files. Any possibility of there being an option in Nero for users to choose which extension they want when they create/convert/encode files?

Also of note is dbPowerAMP and Foobar2000 which both already support both file extensions.

WinAmp 5.02 plays both .m4a and .mp4 files which is great, but its encoder/ripper appears to be hard coded to only encode to .m4a currently (wish it could save to both extensions and give users a choice of which extension they wanted).

The potentially promising upcoming Real Player 10 Gold (non-beta) is said to playback HE AAC and AAC LC files. I wonder if they will support both .m4a and .mp4 file extensions for playback (and/or encoding with their Real Producer)?