Creating Chapterised Mp4's

[jonathan_phang]

Hi all,

I have recently got an ipod and must say that its actually quite decent to use bar a few niggles, but one thing is bugging me. I listen quite a bit to live recordings of sets that trance DJs play at clubs, and hence are about 1.5/2 hours+ in length.

I used to able to use CUE sheets to burn them to cd in specific tracks, so that i could jump several tracks ahead, and that was fine, but if i do this for the ipod, there are jumps at the point of track transistion, as the ipod doesnt really do seamless playback.

However, i signed up to a radio 1 podcast just to see what the fuss was about and they can be up to 30mins but you skip through bits of them as chapters, but if you dont its all seamless. They are mp4 audio files i think. Does anyone know of a way to do this on a PC. i've googled a little and all the solutions that i have come up with are currently for Mac only.

Thanks for any help

JP

[arthurleung]

Try altering the Che sheets yourself and move the start time back about 2 seconds?

[jonathan_phang]

But CUE sheets are only good for creating a CD, on which the standard ones are fine. The problem is that once you have the traks separated into mp3's when they get uploaded to the ipod, then its all there, but mp3's inherently play with gaps/pauses between them.

The limitation seems to be with the ipod firmware, so no-one has any further ideas, it must be possible...

[capt_cornflake]

I don't know about mp4s but I fairly sure mp3s are encoded in discrete chunks of bytes.
I can't see an obvious way to get around it, unless the track breaks at exactly the right point.

It's not so much a problem with the ipod firmware, as the mp3 specification.

Saying that though there may be some encoding software that would automatically allow for this, but I'm not aware of any...

Of course it is possible to develop firmware that will remove the space at the end of the track (rockbox, for example), but it doesn't seem to be a high priority for most the mp3 player manufacturers.

[charleski]

The chapter feature of m4a files is a non-standard Apple extension. There is a supposed 'standard' for MP4 chapters, but no-one uses it and it's enormously complex. doom9.org will have more info on this in the forums.

Apple has a tool to insert chapters that your iPod will read, but unfortuantely they want people to use Macs for some reason.

[autopilot]

It's not so much a problem with the ipod firmware, as the mp3 specification.

Actually it's both, although the lastest version of the LAME encoder (coupled with a decent ripper, like EAC) can produce MP3 files which don't have the offending padding frames. There is no reason that AAC files cant be encoded this was either, but the only 2 formats that i know and use that where designed for gapless playback from day one, are Ogg Vorbis and FLAC.

It's posible to get gapless playback from badly ripped (make that standard) MP3's with a clever bit of trickery, Foobar and Winamp manage just fine. However, the iPod is a dog for gapless playback and this is the single main reason why i cant/wont buy one.

Anyway, AAC this the primory format supported by the iPod which supports chapters, as well as MP4 (basically the same thing). This is you best option with an iPod really. And as you had the good sense to rip your CD's to an image + CUE sheet, you can load the cue sheet up into Foobar2000 and convert to a single file using the CUE sheets to set the chapters in the right place. It's not easy, but worth the effort...

Set Foobars converter options to use neroaacenc.exe ( http://www.nero.com/nerodigital/eng/...tal_Audio.html ). Then load CUE sheet and highlight all the tracks - then rightclick and select 'Convert to album image(s) with cuesheet(s) or chapters.' Job done.

It may also be posible to directly rip you CD's to AAC's with chapers using EAC, But people have had mixed results. This thread on HA might be off use to you - http://www.hydrogenaudio.org/forums/...howtopic=44275

The other option would be to use a custom firmware for the ipod. Never done this myself, but i know there are ones available tht support gapless and better formats too, like ogg etc. Not sure if there are any that can read CUE sheets, like foobar etc, but that would be nice

Dom.

[Funkstar]

good info there Dom

(why the name change btw?)

[autopilot]

good info there Dom

(why the name change btw?)

Because i had a few different names that i used on various forums and online services. Wanted to use the same name on all of them, and prefered 'autopilot' for some reason. Maybe 'audiopilot' would be a better name though.

BTW Funkstar, does Slimserver support and read AAC/MP4 Chapters? Never really looked into it - but it would be nice if SS could read and view them as albums, in much thge same way as it does with CUE sheets

[autopilot]

One other thing with the method i posted above - I just tested it with Foobar using an image file (FLAC) and cue. Using the standard settings, Foobar seems to copy the tags across to the MP4 file - so some of them are the same tags as the FLAC file had. You may need to edit foobars tag formating strings or use a util like MP3Tag or Tag&Rename to clean them up if you need to - you can also add the album art with these (not sure if Foobar will copy the album art over to the MP4, maybe it will?)

[Funkstar]

Because i had a few different names that i used on various forums and online services. Wanted to use the same name on all of them, and prefered 'autopilot' for some reason. Maybe 'audiopilot' would be a better name though.

Thought it might be something like that

BTW Funkstar, does Slimserver support and read AAC/MP4 Chapters? Never really looked into it - but it would be nice if SS could read and view them as albums, in much thge same way as it does with CUE sheets

I have no idea. I only use FLAC with SS. The only time i've played around with AAC/MP4 was when i had my library converted to that from my K750, but it became a pain to manage, so i deleted it all and just use MP3 for it and my AV500. If they don't support it, you can always ask and open a bug/enhancement request for it.