Posted by fred-bloggs on 07/26/06 10:15

2privatus@comcast.net wrote in
news:1153871674.209937.319850@i42g2000cwa.googlegroups.com:

> fred-bloggs wrote:
>
>>
>> For the mp3s you already have try fixing the seek tag with vbrfix,
>> mp3trim or foobar2k.
>>
>> If that solves the problem, in future try encoding wavs from Audio
>> Cleaning Lab with Razorlame.
>>
>> --
>> fred
>
>
> Fred,
>
> Thanks for referring me to vbrfix. I've processed my Mp3 lecture
> series -- which were encoded using VBR -- through it, and then
> imported the resulting files into iTunes. The resulting files showed
> play durations that were more reasonable (somewhere around the
> approximately 45 minute durations of each lecture). However...
>
> The problem persists: When played in iTunes, these vbrfix'ed Mp3
> lecture series files still "skip ahead" to the next file in the
> series, rather then playing themselves out to the end.
>

Ipod and Itunes have always had problems with VBR mp3s. Apple really
should have fixed it by now. Do you have the latest soft/firmware?

> Observation:
>
> When played in Windows Media Player 10 (WMP10), both the "original"
> (un[vbr]fix'ed) and the "altered" (vbrfix'ed) Mp3 play themselves out
> normally to the end of the file. However, the durations shown for
> these two files are different: The original (un[vbr]fix'ed) files show
> a longer duration than do the altered (vbrfix'ed) versions.
>
> Examples:
>
> "Original" Lect_02.mp3 duration is shown as being 45:13
> "Altered" Lect_02.mp3 duration is shown as being 43:38
>
> "Original" Lect_08.mp3 duration is shown as being 46:44
> "Altered" Lect_08.mp3 duration is shown as being 45:00

Assuming WMP is at all accurate (?) this implies that the original seek
index in the VBR header was incorrect. Test them in WinAmp rather.

>
> BTW: The amount of audio "lost" when the files are played by iTunes
> does not correspond to the difference in these durations. By my
> reckoning, only the concluding 20 seconds of the files are "skipped
> over" as iTunes shifts from one lecture to the next in the sequence.
>
> Question:
>
> How do I set up vbrfix -- or any other Mp3 VBR ''fixer'' -- to correct
> this "skip ahead" problem when these Mp3 files are played in iTunes
> (and then, in my iPod)?
>
> Thanks,
>
> 2privatus@comcast.net
>

As Don says, your best bet is to use constant bitrate encoding,
Itunes/Ipod should surely cope with that?

As a hack, you could add 2 minutes of silence on the end of each lecture
in Audio Cleaning Lab.

--
fred

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