File extensions of MPEG

[moonie]

Hi guys,
I was searching around the internet for an ftp or download site to download MPEG-4 Video Test Bitstreams. I've done the same for MPEG-1 and 2 before this. Suddenly, I realise I have no idea what file extensions referred to MPEG-4.

Here's a little list of what i gathered from the internet.

m15 and m75 is Apple MPEG-1 video
m1a and m2a is Apple MPEG-1/2 Audio
m1v is MPEG-1 IPB only video or system stream

m2p is MPEG-2 program stream format file
m2s is MPEG-2 audio and video (system stream)
m2v is MPEG-2 video only
m3a is MPEG Archive Enhanced. .m3u Playlist File
m3u is MPEG URL???, MP3 Playlist File?

mp+ is MpegPlus Audio File (replaced by .mpc)
mp1 is MPEG Audio Stream, Layer I
mp2 and mp2v is MPEG Audio Stream, Layer II
mp3 is MPEG Audio Stream, Layer III (?Sharp MZ-series Emulator File)
mp4 iVAST MPEG-4 (hold BIFS-Binary Information for Scene representation)
mpa is MPEG-1 only audio Layer I, II or III (? mostly Layer I and II)

mpe, mpeg and mpg could be anything
(? mpg usually only Xing-format, only I-frame)
mpe is MPEG Movie Clip
mpg is MPEG Animation
mpg is MPEG-1 System Stream
mpm is MPEG Movie
mps is an MPEG-1 audio and video file (IPB system stream)
mpv is MPEG-1 IPB only video (sometimes even .vmp), MPEG Movie Clip

So, does it mean that I should download .MP4 files since I'm looking for MPEG4 standard video file for testing? By the way, would anyone have any idea where I can find MPEG-4 videos? Thanks.

Li'Cyndi

[adam]

Mpeg4 files have an .avi extension.

There arent alot of non-commercial mpeg4 videos available for download on the internet. You could probably find some mpeg4 encoded movie trailers, sorry I don't have any links.

[kayfam]

Adam,
Not to overstep my bounds here, but true mpeg-4 files have the .mp4 file extention. As for DivX files, they are mpeg-4 compliant, but use the .avi file extention. Also you can find some sample's of mp4 files over at Apple.com in the QuickTime section.
http://www.apple.com/quicktime/gallery/mpeg4.html

[moonie]

Thanks Adam, In the process of my search, I was puzzled when the mpeg 4 movie trailers (from Divx) turned out to be .avi.

KayFam, I visited the Apple site before reading your message. Trouble is, is there anyway I can actually save the movies? They can't seem to be saved using right-click "Save Target As ..." All I could do was watch the video on my QuickTime player ....

Li'Cyndi

[kayfam]

moonie,
Yeah you can save them, but you need QuickTime Pro to do it. Go to the file tab and select save, then in the following dialogue select "Make movie as self contained", then click save. That's all there is to it.

[adam]

Adam,
Not to overstep my bounds here, but true mpeg-4 files have the .mp4 file extention. As for DivX files, they are mpeg-4 compliant, but use the .avi file extention.

Anything that uses mpeg4 compression is an mpeg4 file. There are lots of mpeg4 codecs out now, and many more in development. The one you linked to is just apple's format of choice. The majority of the mpeg4 video's on the internet use an mpeg4 codec in an avi file container.

[moonie]

Hi guys...

Kayfam, I am using Apple QuickTime Pro 6 (free version) on my WinXP. At the apple download page, i'd select Fast Start Download/Streaming Video. I even chose Edit>Preferences>Browser PlugIn>Save Movies in Disk Cache. Problem is, I don't see any "Save" or "Make Movie as Self Contained" option anywhere. I checked out the QuickTime help, and it mentioned some "down arrow" at the playback controls which would allow me to "save as QuickTime Movie". I can't find the down arrow in reference. Lastly, the help did mention that if the menu item is not available, the movie is authored and cannot be saved. Well, I tried each and every one of the movies on that Apple page and couldn't save any of them.

Dear Adam, thanks for your explaination. That helps alot in the understanding why some files were in avi format. Enlightening.

Cyndi

[kayfam]

moonie,
You need to purchase a key from Apple.com (last time I checked $29.99) to unlock all the features of QuickTime Pro.

Adam,
I have to agree and disagree with your statement at the same time, but that's not really the issue. One thing we do agree on is that there is more than one variation on the MPEG-4 standard (if you can even call it a standard). The folks at Divx have their flavor, so does Apple, Real Networks, and the upcoming release of Corona from Microsoft to name few. As you know more are out there and it would take too long to list them all, but none are interchangeable with the exception of DivX and require proprietary software to be played back on. As for my statement that a "true MPEG-4 file uses the .mp4 extension" was an error since as of this writing no such standard exists when compared to MPEG-1/MPEG-2 unless you consider a very loose set of guidelines that were established by the Moving Picture Experts Group a standard. You can find more information at:
http://mpeg.telecomitalialab.com/standards/mpeg-4/mpeg-4.htm

[adam]

The mpeg4 standard itself is completely finalized. Mpeg4 is just as much of a finalized standard as mpeg1 or mpeg2, they all just start out as writing on paper anyway.

The codecs utilizing mpeg4 are just in early stages, well only compared to mpeg1 or mpeg2, because the format itself is still relatively new. Each codec does not represent a separate standard, or even another "flavor" of the standard. They all use the mpeg4 standard, they just utilize it through different lines of code.

[kayfam]

Adam,
I can see where these posts are going and it was not my intention to start a debate. I did however see an opportunity to open a discussion on MPEG-4 and the lack of standardization on how it’s being implemented. To quote you “They all use the mpeg4 standard, they just utilize it through different lines of code.” then wouldn’t the end result be the same and accomplish the same task? I agree MPEG-4 is in it’s earliest stages of development, but if such an approach had been taken with MPEG-2 I dare say none of us would be posting anything in this forum since DVD’s, SVCD’s, and Broadcast Satellite Television wouldn’t exist. Various hardware/software manufacturers use their own proprietary methods to encode and to decode MPEG-2, but the end result is that it comes out in a format that is universally recognized, not so as is the case with MPEG-4. Since MPEG-4 is being considered as the successor to MPEG-2 compression in the next generation of DVD’s and broadcast television I do consider this something of an issue, but perhaps this topic is an issue better off left in the hands of the experts. Any comments, suggestions or advice you have I’m willing to listen to, but I’m finished with this thread.

[adam]

Kayfam I am not trying to start a debate with anyone, I am simply laying out the facts.

The mpeg4 standard is as finalized as its going to get. Total hardware and software support for that standard is what we are all still waiting for and this will not happen until one single mpeg4 codec or a set of mpeg4 codecs becomes so superior to all others that they become an industry standard.

[jeex]

pop quiz hotshot.. what was mpeg 3 video's originaly going to be primarily used for?

hdtv.. but it fizzled out..

the bitrates topped out at 40+mbps.. wow..

[kayfam]

Adam,
In the end you’re correct of course. I want apologize for any misunderstandings. Viewing your last post does put the whole thing in a different perspective. Increased competition in this area can only lead to a superior codec for all. I guess I just wasn’t taking whole picture into consideration.

[kayfam]

jeex,
On the assumption that this going to be deleted anyhow, your reply to this topic was about as relevant as to how to make a turkey sandwich on rye. And I really like that nice Nazi Logo on your website.
Hiel Hitler you *******!

[jeex]

jeex,
On the assumption that this going to be deleted anyhow, your reply to this topic was about as relevant as to how to make a turkey sandwich on rye. And I really like that nice Nazi Logo on your website.
Hiel Hitler you *******!

i've never claimed that anything i've said ever had any relevance to anything.

and i've redesigned my website. i hope you like it, well actually, i dont care

[kayfam]

bump