M4A - AAC pausing

[SebZ]

Hi, I recently copied over some songs from my friends iPod and all the songs were in Apple's M4A - AAC format.
I tried playing it and it will play for 1 second to 3 1/2 seconds, pause for 3 seconds then continute to play, then pause, etc.

While watching the 'NowPlaying' screen, the Hard Drive would be accsessed every time the song would pause.

What am I doing wrong?

[Yotto]

Does it happen only with the AACs, or does it happen to all your music on your Rockbox once you did this?  If it's the former, is there any chance you set the "anti-skip buffer" to something huge?  Even if not, it may be worth trying to reset it to something like 5 or 15 seconds.

[bk]

You didn't mention what player you use, however the AAC codec does not run in realtime yet on most devices.

[Suicide_Guy]

I'm having the same problem with both .m4a and .aac files. I'm using the iAudio X5L with the 24/09/2006 daily RB FW. I checked my anti-skip buffer and it is set to 5s.

[markun]

Some AAC optimizations were committed yesterday:

Apply a bunch of simple AAC decoder optimizations. Biggest speedup is on ColdFire targets, but ARM targets benefits too. Allows realtime playback of some AAC files on Iriver targets (H1x0, H3x0). Remove support for some rarely used AAC profiles to reduce code size a bit.

Could you guys test if you still have this problem with the latest build?

[RonH]

Could you guys test if you still have this problem with the latest build?

So far, so good.  I even got the [software] equalizer going and it only skipped once while I was setting the high freq.

I do notice that the menu/scroll is much slower, but nice tradeoff for now IMO.

Edit: iPod 5g, 1.2 fw

[Suicide_Guy]

No change noticed on iAudio X5L, but that makes sence, since the CVS says it's mainly for iRiver anyways.

[Llorean]

No, it says the optimization is mostly for Coldfire targets. It says the speedup to realtime was noticed on iRiver targets. Since the X5 is Coldfire too it should at least have noticeable benefit as well I should think, unless they aren't compiled in for it for some reason.

[theory_87]

SO is that added for the latest ipod nano built?

[bk]

On the iAudio X5, 128kbps and 192kbps AAC files play in realtime now at about 85% boost. 320kbps files skip every 15-30 seconds.

[Suicide_Guy]

I have some 128kbps .m4as on my iAudio X5L and they still skip. I even tried varying the anti-skip buffer from 5s-1min with no change. This is with the latest daily, too. This only occurs with my .m4as. I don't have problems with any .mp3s I have. It just cuts out every 5s or so. If you want, I might be able to record what the sound sounds like if that would help at all. I guess they must have missed the compile or something. I did notice that the daily's file size was about half of what they had been. I don't know if that has anything to do with it, but I can't notice any change.

[senab]

Nope, every MP4 i've used since the optimizations have worked superb.

I did a test earlier, each played back in realtime:

128kbits VBR - 70% CPU Boost
160kbits VBR - 75% CPU Boost
192kbits VBR - 84% CPU Boost

These values were the same for both iTunes and Nero encoded AAC's.

[bk]

This is with the latest daily, too. This only occurs with my .m4as.

Try the latest CVS bleeding edge build. The optimizations may not have been picked up in the daily build yet.

[Suicide_Guy]

Just picked up the bleeding edge and it works like a charm. You guys are amazing.