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Current state of ac3+aac mp4 creation

Stayed up a little later. The quick fix I had for changing "levels" that were originally 5.1 or 4.1 in the .MKV's in h264info didn't quite work out; green frame all the way through..

So uh, unless the h.264 stream is in someway Apple TV compatible, I'm **** out of luck here.
 
I've given up. I spent another four hours this morning and I've come to the conclusion that you just need to reencode, which is a shame.
 
Alphy said:
I've given up. I spent another four hours this morning and I've come to the conclusion that you just need to reencode, which is a shame.
Click to expand...

It's a shame that you believe that you're entitled to copyrighted material free of charge.
 
Avatar74 said:
It's a shame that you believe that you're entitled to copyrighted material free of charge.
Click to expand...

Enlighten all of us as to where EXACTLY in this thread you see mention of copyrighted files.

So please, f**k off.
 
You must not be aware that a .mkv can contain subtitles and DTS audio, where as a .mp4 cannot. I've captured a number of off-the-air HD broadcasts and encoded them to .mkv, however I've deleted the original source.

Think before you start making assumptions.
 
Actually you need to put an ac3 into the mp4, not 5.1aac. Appletv won't generate ac3 on the fly (what 5.1 receivers expect) but it will pass through an ac3 track muxed into an mp4 while decoding a stereo aac track at the same time for non 5.1 output.
 
Alphy said:
You must not be aware that a .mkv can contain subtitles and DTS audio, where as a .mp4 cannot. I've captured a number of off-the-air HD broadcasts and encoded them to .mkv, however I've deleted the original source.

Think before you start making assumptions.
Click to expand...

Actually I didn't know that, because in the UK we don't have over-the-air HD unless you pay (through the nose) for it. It should be coming within the next few months, though. Out of interest, what are you using to capture and encode?
 
My primary source of encode/transcode material is Transport Stream captures - ie mpeg2 video and AC-3 audio. So my source for AC-3 audio comes from neither DVD ripping nor downloaded files, but rather as a seperate file produced from demuxing the ts file.

I would much prefer to keep the original audio rather than re-encode it to aac. A google search led me to this discussion...

So, in a nutshell, is there a tool that will allow me to mux my ac3 file as-is into the mp4 container (for playback on my AppleTV)?
 
ajv said:
I found this thread over on the handbrake dev forum:

http://forum.handbrake.fr/viewtopic.php?f=4&t=4726&st=0&sk=t&sd=a

It looks like eddyg is the only guy outside of apple to figure out how to get mp4 ac3+aac working so far. I'll shoot him an email and see if he has any interest in getting his patch working with the mp4creator command line tool that's part of the mpeg4ip library he's using.
Click to expand...

Ah nope, I did it for one reason only, so that I could have AC3 on my front room ATV, and AAC on my bedroom one from the same file encoded using HandBrake.

Any other developer is free to incorporate those changes into mp4creator or any other program as they see fit.

Either that or change HandBrake to accept mkv as a source ;)

Cheers, Ed.
 
plugh said:
So, in a nutshell, is there a tool that will allow me to mux my ac3 file as-is into the mp4 container (for playback on my AppleTV)?
Click to expand...

In a nutshell - yes - HandBrake will take an MPEG2 transport stream, with AC3 audio from an over the air broadcast and mux that into an mp4 container for use on your ATV.

If the source with the AC3 is anything other than an MPEG2 transport stream, then in a nutshell, no, there is nothing available at this time. The closest is VisualHub and it's .mov container "trick".

Cheers, Ed.
 
eddyg said:
In a nutshell - yes - HandBrake will take an MPEG2 transport stream, with AC3 audio from an over the air broadcast and mux that into an mp4 container for use on your ATV.

If the source with the AC3 is anything other than an MPEG2 transport stream, then in a nutshell, no, there is nothing available at this time. The closest is VisualHub and it's .mov container "trick".

Cheers, Ed.
Click to expand...
To make sure I'm parsing the above correctly...

Handbrake will accept the transport stream containing ac3, but not the ac3 sitting in a seperate file that I demuxed from it?

IE, I demux it, process the video, then want to mux the processed video with the demuxed audio...
 
Correct me if I'm wrong, but from my limited understanding of encoding it seems that right now I can encode my mkvs into MP4s with 2-channel AAC audio and H.264, and then later on when the technology becomes available, remux my mp4s to include AC3, without any reencoding of the initial two-channel stream and H.264 video?

I want to make sure my HD conversions are "forward-compatible" before continuing converting the hundreds of gigabytes I have of them.
 
refulgentis said:
Correct me if I'm wrong, but from my limited understanding of encoding it seems that right now I can encode my mkvs into MP4s with 2-channel AAC audio and H.264, and then later on when the technology becomes available, remux my mp4s to include AC3, without any reencoding of the initial two-channel stream and H.264 video?

I want to make sure my HD conversions are "forward-compatible" before continuing converting the hundreds of gigabytes I have of them.
Click to expand...

Theoretically yes - assuming someone provides a tool to remux the AC3 stream from a mkv into an existing mp4 whilst retaining the AAC in that mp4.

Cheers, Ed.
 
How best to play back these files?

Slightly OT (but not as much as that IP debate up there), how do you guys play back Handbrake-encoded h.264/ac3 mp4 files? I don't have an AppleTV, I'm using an XP-based HTPC in my living room. Mplayer and VLC don't seem to be able to play back the audio. I've tried the VLC nightlies and that doesn't seem to work, either. Quicktime doesn't work. Any other suggestions?
 
Another slightly on/off topic.... If I have say an mkv file and I want to convert it for playback on my AppleTV, but lets say I have a couple requirements:

  1. Must keep AC3 audio.
  2. Must keep resolution so if it were say 1280 x 536 it needs to stay that way
  3. End up in a .m4v container

Anyone have a suggestion for mkv -----> .m4v while keep the above? I have been using VisualHub but that just gives me a .mov (although it keeps the AC3) so it gets me part of the way.
 
entropy1980 said:
Another slightly on/off topic.... If I have say an mkv file and I want to convert it for playback on my AppleTV, but lets say I have a couple requirements:

  1. Must keep AC3 audio.
  2. Must keep resolution so if it were say 1280 x 536 it needs to stay that way
  3. End up in a .m4v container

Anyone have a suggestion for mkv -----> .m4v while keep the above? I have been using VisualHub but that just gives me a .mov (although it keeps the AC3) so it gets me part of the way.
Click to expand...
You can't, which is the point of this thread, so you're very on topic. :D

MP4 = M4V, from my knowledge M4V is an Apple way of designating MP4s that "should" be opened in iTunes. Right now, AC3 can't be muxed into MP4s.
 
refulgentis said:
You can't, which is the point of this thread, so you're very on topic. :D

MP4 = M4V, from my knowledge M4V is an Apple way of designating MP4s that "should" be opened in iTunes. Right now, AC3 can't be muxed into MP4s.
Click to expand...
Glad I am on topic :)

Well I guess I am wondering how is Handbrake doing it? I mean I put a DVD in and end up with both a stereo AAC and the pass through AC-3 in an .m4v?
 
refulgentis said:
You can't, which is the point of this thread, so you're very on topic. :D

MP4 = M4V, from my knowledge M4V is an Apple way of designating MP4s that "should" be opened in iTunes. Right now, AC3 can't be muxed into MP4s.
Click to expand...
That's not true. Handbrake is doing this right now. The .mov container is a limitation in the way VisualHub has chosen to create files with an AC3 soundtrack.
 
entropy1980 said:
Glad I am on topic :)

Well I guess I am wondering how is Handbrake doing it? I mean I put a DVD in and end up with both a stereo AAC and the pass through AC-3 in an .m4v?
Click to expand...

Details are at the Handbrake board links in this thread, but basically it appears to me as I'm reading now that someone needs to take the time to "incorporate those changes into mp4creator or any other program as they see fit. Either that or change HandBrake to accept mkv as a source" as eddyg says above.

It would be incredible if this happened soon, since soft subtitles for Quicktime were recently settled over at Handbrake and are trivial, I haven't done any actual research into chapters but I'm pretty sure they're trivial, so the only barrier left is getting 5.1 AC3 and 2.0 AAC into the same file before Apple devices can support every feature I can think of for video.
 
NightStorm said:
That's not true. Handbrake is doing this right now. The .mov container is a limitation in the way VisualHub has chosen to create files with an AC3 soundtrack.
Click to expand...
I know it *can* be done, but there is no mp4 muxer right now that will do it properly, so in practice it can't be.
 
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