Thinking of switching to mp4...

[jellysandwich]

I've been using mkv up until now, but have been thinking of switching over to mp4. First, it looks like some hardwares can/will support mp4 files, while mkv would be strictly for PCs. Second, it seems like mp4 is getting a lot more attention these days. For example,it has virtualdub-like editing (http://forum.doom9.org/showthread.php?t=103918) and menus (http://forum.doom9.org/showthread.php?t=66583).

The only problem I'd have would be the lack of official support for ogg audio and vobsubs... What do you guys think?

js

[bond]

we think that if you want to use vorbis audio you shouldnt use mp4

[jellysandwich]

That's unfortunate. Guess I'll stick with mkv for now.

js

[Elias]

That's unfortunate. Guess I'll stick with mkv for now.mp4 wasn't made for vorbis. It was made for MPEG-4 content. IMHO, nothing beside MPEG-4 content should be in mp4. Period.

[MrWizard]

Okay I have a couple of questions along these lines...

I am debating which to use between MP4 and MKV, as well - not even considering AVI lol. Practically everything I do is AVC video and either AAC or AC3 audio.

The reason I lean towards MKV is because, on the off chance that I do something with another codec that MP4 does not support, I would prefer not to have to switch containers - keeps things consistent. On the other hand, MP4 is a recognized standard and may be compatible with hardware MP4 players in the future.

MKV gives me the option of using AC3 audio where, it is my understanding, MP4 does not (at least it is not officially supported?). When I have used the "transcode" quality level when going from AC3 to AAC, I have not noticed a difference in playback (although the AAC ended up being maybe 75% the size of the original AC3). However I do not have huge surround sound speakers - I'm using my computer so it is hard to tell if there really is a difference. So my first question is this; if I were to transcode from AC3 to AAC (Nero) at the highest possible quality, is there a noticable difference? If so, I would prefer to stick with the original AC3 audio and, by proxy, MKV. If not, I would be less likely to dismiss MP4.

My other question is in regards to performance, as far as CPU and memory is concerned. I am working on 1080p material at 24 fps. It takes most of my CPU power to play it back at full speed. So, does one have a bigger overhead than the other? Also, does one allow for a faster seek time than the other?

You may notice I tried my very best to avoid the "which is better" question :)

Edit: Thanks in advance for any answers you can give me!

[GodofaGap]

I don't know if it makes much sense to re-encode ac3 to the highest quality aac, because your filesize gain would probably be zip. The only one who can determine if you can hear a difference is you. I do wonder if saving 112 kbps on audio (your 75% of 448 kbps AC3) is really worth the effort of doing it and discomfort of thinking there might be something wrong.

The CPU hit of any container is almost 0 too, so that is no reason to choose one or the other.

All in all, whatever you choose, I think it will hardly matter for the quality of the end result. So perhaps hardware considerations are more important, but who says you will be able to play anything on your HD-DVD or Blu-Ray player if it's not heavily infested with DRM. :devil:

[darkavatar1470]

If you belive the "Home Theater PC" Future,(and buy one) then hardware playback support wouldn't be much of a problem.......

[MrWizard]

Thanks for the replies. The point about the Home Theatre PCs is a good one. As far as encoding to the highest AAC, that's when I get the 25% size drop. I was just wondering if someone with really nice speakers had tried the same thing :) Good point though, perhaps AC3 really is the way to go.

I had heard that Matroska has faster seek times when it comes to H.264.


But, if the container is irrelevant to playback speed, is there any other way for me to squeeze out a couple of CPU percentiles? Some of my 1080p files are ALMOST playing back realtime, I just need a little bit more... 2.8 GHz P4, 2 GB DDR2, SATA2 HD, CoreAVC demo codec (I'll be buying it when it comes out on the 15th :D hurrah). So, any suggestions? I had Hyperthreading enabled on the PC but turned that off, as CoreAVC was/is not a multi-threaded tool and it pretty much disallowed playback.

Perhaps this warrants a different thread? I dunno...

[shon3i]

I am using mkv beacouse mp4 has some problem with srt subtitles and country codes.

[Elias]

beacouse mp4 has some problem with srt subtitles and country codes.No, it does not.

[JoeBG]

I am using mkv beacouse mp4 has some problem with srt subtitles and country codes.

Never realised this.

[Sharktooth]

I am using mkv beacouse mp4 has some problem with srt subtitles and country codes.
update mp4box........

[XmSurfer]

mp4 wasn't made for vorbis. It was made for MPEG-4 content. IMHO, nothing beside MPEG-4 content should be in mp4. Period.

Private Streams?

[Elias]

Private Streams?What's the point? You're only doing damage on the container and its codec compatibility that way. Better use Matroska instead.

[XmSurfer]

What's the point? You're only doing damage on the container and its codec compatibility that way. Better use Matroska instead.

It was my understanding from what I have read that private streams are part of the standard for just such a purpose and that mp4 can have private streams and still be spec compliant. Did I read something that was incorrect? If not, then what is the problem with private streams, specifically? If the MPEG saw fit to place it in the standard, why should it not be used?

[Elias]

It was my understanding from what I have read that private streams are part of the standard for just such a purpose and that mp4 can have private streams and still be spec compliant. Did I read something that was incorrect? If not, then what is the problem with private streams, specifically? If the MPEG saw fit to place it in the standard, why should it not be used?Just because MPEG made it possible to put anything in mp4, it doesn't mean that you should. They haven't standardised the use of vorbis in mp4, just how to place any stream in mp4 (that includes vorbis). mp4 isn't really a good choice if you want to use non MPEG-4 cocecs. That's what Matroska is for.

[XmSurfer]

Just because MPEG made it possible to put anything in mp4, it doesn't mean that you should. They haven't standardised the use of vorbis in mp4, just how to place any stream in mp4 (that includes vorbis). mp4 isn't really a good choice if you want to use non MPEG-4 cocecs. That's what Matroska is for.

In other words, it really is a matter of personal preference.

[Sharktooth]

in other words hardware players capable to play mpeg4 formats in .mp4 wont (likely) reproduce private streams...

[Elias]

In other words, it really is a matter of personal preference.In other words a very bad preference.

[XmSurfer]

in other words hardware players capable to play mpeg4 formats in .mp4 wont (likely) reproduce private streams...

Personally, I've never really cared for hardware players since they seem so limited compared to a laptop, TV out, and a software player. Granted I've never used the TV out since I rather watch on my laptop. But it is there if I choose to use it. However, if the encoder decides that hardware playback is important, then he should act accordingly. If he does not think hardware playback is important, then he should put whatever he wants in mp4. I'm sure he'll always be able to find some software player to play it. If not, and that is a big IF, then Matroska is always there to lend a hand.


In other words a very bad preference.

You saying it is a bad preference, doesn't make it any truer that if I sad it was a good preference. The only person qualified to decided if it is a good or bad preference is the encoder. That is why I sad it is a matter of personal preference. What is a bad preference for Person 1 doesn't make it a bad preference for Person 2 and vice versa.

If a guy wants to put vorbis in a mp4 and doesn't care about hardware playback, why shouldn't he? It is his material after all. I can't think of a reason, short of trying to advance some sort of purity of the container agenda, why he shouldn't do it. This doesn't make sense since I thought private streams are part of the standard and wouldn't make the mp4 less pure. Maybe I'm not looking hard enough. But for the life of me I don't see why not. Anyway, I will not debate it further since I don't see the point in debating a personal preference. Unless there is some compelling reason otherwise, I say to each his own when it comes to what streams to place in mp4.

[GodofaGap]

The only thing I can think of to not use private streams in MP4 is that for any random player/playback filter (of course no one selects those randomly), they might work, but also might very well not work. With Matroska any supported stream at least *should* work (and mostly they do).

Personally, I don't see the point of MP4 for personal use if not related to hardware, but that's just personal preference too of course. If it works, it works, so who cares? :)

[Elias]

You saying it is a bad preference, doesn't make it any truer that if I sad it was a good preference. The only person qualified to decided if it is a good or bad preference is the encoder. That is why I sad it is a matter of personal preference. What is a bad preference for Person 1 doesn't make it a bad preference for Person 2 and vice versa.

If a guy wants to put vorbis in a mp4 and doesn't care about hardware playback, why shouldn't he? It is his material after all. I can't think of a reason, short of trying to advance some sort of purity of the container agenda, why he shouldn't do it. This doesn't make sense since I thought private streams are part of the standard and wouldn't make the mp4 less pure. Maybe I'm not looking hard enough. But for the life of me I don't see why not. Anyway, I will not debate it further since I don't see the point in debating a personal preference. Unless there is some compelling reason otherwise, I say to each his own when it comes to what streams to place in mp4.Why are you being stubborn about this? mp4 is not a universal container. It is not a good choice for codecs that aren't approved by MPEG and the MPEG-4 standard. Yes, you can do it, but it's still not a good choice. I don't see the point with using vorbis in an ill-suited container like mp4 when you have an excellent container like Matroska available, and recommended for such use. I would never do it. And yes, the "purity of the container" agenda is important.