AVI/Xvid->MP4/Xvid w/o recompressing?

[chconnor]

Hi there -

new to the video format world, head still spinning... :-)

I'm rendering from a program that can only go to AVI (older version of Vegas; it can go to other things, but i think AVI is the only relevant one for this question...).

My goal is to end up with a MPEG-4 ASP MP4 that a standard embedded quicktime or realvideo player can show (without the users having to download any other codecs or anything, aside from the player itself.)

I figure I should render to AVI with the Xvid codec and then convert to .mp4 ?

- can I be sure with any converter that it will not recompress the video? I'm not sure if that's possible, but I'd like to know if it can "take the Xvid/mpeg-4 stream out of the AVI container and put it in the .mp4 container", so to speak, without decoding and re-encoding... audio is ADPCM 44.1/stereo 4-bit due to limitations in Vegas, but I could also render it uncompressed audio and have the converter compress that... (it's a music video, so the audio is important.)

- I suppose i could also render it totally uncompressed out of Vegas and use an AVI->MP4 to do the encoding? Maybe that makes more sense?

- It seems like the only reasonable audio format that both quicktime and the .mp4 container support is MP3; is that correct? Should I use CBR only for the MP3? I've heard that VBR MP3s can have sync issues? Maybe not with .mp4?

- any pointers towards a good free converter for this stuff (technical is OK, i learn quick, don't need a fancy UI)? I google it and 4000 products show up...

Thanks a million,
-C

[jagabo]

Yamb (GUI for MP4Box) can remux your AVI into an MP4 container.

[chconnor]

Beautiful, thanks! Even if I don't use it for this project, it looks super useful.

I will continue to do my homework, but if anyone has any further advice on:

- what type of audio compression to use in an mp4/mpeg4 to ensure sync

- a good converter to take uncompressed avi audio/video to mp4/xvid

... it would be very welcome.

Thanks again,
-c

[chconnor]

To refine my question a bit:

I rendered to uncompressed video/audio in an AVI, and tried AnyVideoConverter to make mp4's and FLV's, and it works well, but for the mp4 it doesn't allow me to adjust xvid codec settings... Is there a free or low-cost converter that allows tweaking of those settings in the codec?

Then I rendered it out of Vegas as avi/xvid, with the audio uncompressed. I tried to use VLC to leave the video as it was and transcode only the audio to aac (which i take it is AKA mp4a, m4a...) into an mp4 container. The conversion seemed to work, but the result was totally herky-jerky (latest version of VLC).

Any other pointers? Again, the goal is a quicktime/realplayer compatible MP4 with (customizable) xvid encoding and aac audio encoding. I am starting with either AVI all-uncompressed, or AVI with only the video compressed.

Thanks!
-C

[jagabo]

AviDemux is free, supports Xvid, h.264, mp3, aac, editing, filtering, etc, and can export as MP4.

[poisondeathray]

Beware the output from avidemux (both x264 and XviD video) have compatibility issues with quicktime player. Not sure why - it works with virtually all other Windows and Linux based media players fine.

If you want quicktime compatible, why not use x264/aac instead of XviD? If you configure the settings right and the server supports it, the next generation Adobe Flash is exactly this format - and you can stream. There is a reason why Apple and Adobe, (even DivX's next format) are all moving to x264/aac - the quality and compression have no rivals.

I would do all your editing in uncompressed, then encode that using a dedicated encoder. Note that you need special settings for compliance with QT (e.g. max number of b-frames, AVC level, macroblock options), but encoders such as MeGUI and ripbot264 have presets to make life easy.

You also mentioned realplayer - I have no idea about this, I didn't know anyone even used it.

[chconnor]

Thanks so much;

Yeah, H.264 sounds great but my understanding is that most quicktime users need to upgrade to the latest version or download a plugin for it, no?

That's all i'm hoping to avoid. I'd like to post the highest quality widely-viewable-without-download videos i can.

RealPlayer - right, obscure these days. But it supports mp4, they say.

So far I've been using AnyVideoConverter to process the uncompressed stuff into mp4/xvid-aac and also into flv and satisfying myself with the barely-tweakable xvid settings AnyVideoConverter provides. I have successfully viewed the results with my quicktime player (ver 6.5.2). Is that enough to ensure compliance or must I do yet another round of research? :-)

And if you tell me that adoption of H.264 is widespread enough that i shouldn't worry about it, then i'm all over that. :-) I read that the current Flash is not very reliable for mp4... that's a big mark against it for my goals, no?

Thanks again!
-c

[jagabo]

That's all i'm hoping to avoid. I'd like to post the highest quality widely-viewable-without-download videos i can.

That's definitely not going be anything MPEG4. It's going to be WMV or MPEG1. Maybe FLV.

[chconnor]

MeGUI is rocking my world right now... thanks for that. But it doesn't seem that you can output mp4's with it when using Xvid... perhaps to protect you from making non-compliant mp4's or something? Weird. I'm going to try using YAMB to remux the AVI i'm required to make... (when using x264 it allows mp4...) Maybe I'm doing something wrong?
-c

[chconnor]

Thanks jagabo; yeah, FLV is what I'm going with for the accessibility issue. I'm just interested to have a "high quality" option that still meets the accessibility goal as best as it can... seemed like mp4/xvid was that answer... and it may still be if I can get this converter house-of-cards to stand up.

The world of video codecs is kind of astonishing, in many ways, good and bad.

-c

[chconnor]

Though I guess i can remux with megui... i'll try that too...

[chconnor]

Things are going great! MeGUI is the greatest thing that ever happened.

One question I'm having a hard time with, though, is configuring xvid to be quicktime compatible. The (invisible) settings that AnyVideoConverter uses with xvid work fine with qt, but I haven't correctly tweaked it yet through megui to get it to work.

Googling, I find only this (which I tried, which didn't seem to be adequate

its very important to have the xvid settings right, or playback in quicktime will fail: no bframes, no qpel, no gmc, no interlacing (nothing xvid4conf frames as advanced on the first tab). these are all features, that require capabilities not currently available in the quicktime player (as of version 6.x) - or in mpeg speak, belong to higher "profiles" of the standard - the windows version reportedly chokes on bframes, while the macintosh version supports them; anyway, bframes are not of much interest in no budget productions. be aware, that quicktime 5 cannot handles these streams. also be aware that quicktime only displays pixels square and will ignore aspect-ratio settings on the stream. when embedding in a web page, the "scale" attribute can be used to correct that behaviour.

I suspect i just need to uncheck a few things, and i'll play with it, but if anyone can point to a comprehensive, current list, that would be awesome.

Thanks,
-c

[jagabo]

Quicktime player was banished from my computers years ago. I suspect the quoted requirements are out of date though. I would avoid qpel, gmc, and interlace as those are problematic on may set-top Divx/DVD players. B-frames (V-VOPs) are quite common now so I would test that in Quicktime. You should probably stick with single B-frames though. If you use b-frames in AVI check whether packed bitstream (a kludge for out-of-order decoding in AVI files) works or not. Many players, software and hardware, don't handle non-square pixels correctly so I would avoid that.

GSpot will show you most of those settings in AVI files. Not in MP4 files though. MPEG4Modifier will show you the packed bitstream status in AVI files.

[poisondeathray]

You might have already decided against it, but I'm going suggest x264/AAC again - why?

The tradeoff is a bit of accessibility, but if you can playback the "high quality" youtube videos, Hi-def Apple Movie trailers, or even stream Adobe Flash Player 9, you can play this format back. They all use the some variation of h.264/AAC. If you CAN'T playback any of these formats, I doubt you are experiencing any hi-def/hi-quality content streaming on the net anyways...

One reason why almost all steaming hi-def formats choose h.264/AAC is the quality/compression ratio. Bandwidth is a concern when streaming hi-def media. You can probably get between 20-50% better compression at low bitrates. At very low bitrates, there is no comparision. The difference is like night & day.

[chconnor]

jagabo - I totally banish quicktime as well, can't stand it... but thanks for the tips.

pdr - ok, you've convinced me. I'm going to study up on 264 settings and go for that. I'll just ride the wave of the future.

A million thanks for the help. I feel almost arrogant in my codec sophistication now (little bit of knowledge is a dangerous thing. )

-c

[lazyhorse]

thanks guys for the links.
i'm trying to convert mp4 (h264) to avi (uncompressed).
surprising how few converters do uncompressed .

poisondeathray is right about h264 / aac.
with any luck, all these tedious formats and codecs could give way to mp4 soon enough.
why not? its universal and well designed like mp3.
how much simpler life would be.

[edit]

ok i searched a bunch of converters, and the winner is that avidemux. thanks jagabo.
it's a video editor like virtualdub, but with so many formats in and out, a converter too.
i found this guide on this forum: How-to-get-started-with-avidemux-edit-and-convert-any-video-format

you happy yet, chconnor ? maybe your origional MPEG-4 ASP MP4 is not so bad an idea.
asp (xvid) is h263, and so unless you are encoding to high def, you don't need h264?
otherwise, widest possible playability? mpg probably.

oh yeah and x264 rocks with the "lossless" compression option, better than bulky raw.
heres the link to the stand alone "video for windows" install: http://sourceforge.net/projects/x264vfw