Posted by Ty Ford on 11/18/05 14:06

On Thu, 17 Nov 2005 17:02:33 -0500, Rick Merrill wrote
(in article <m-2dnTJgsN1lYOHenZ2dnUVZ_sOdnZ2d@comcast.com>):

> Doc wrote:
>> You may have seen my other thread re: OOS audio problems. To recap, when
>> recording to h/d via Firewire passthrough from analog VCR through a Sony
>> Dig8 cam, the audio gets out of sync, it gets progressively worse the
>> farther into the program you get...
>
> This is similar to what will happen if you try (and fail) to convert a
> DVD to MPEG2! DVD have audio recorded in AC3 at 44.1 kHz, while the
> standard for MPEG2 is Level 2 at 48 kHz sampling rate. What happens
> is the 44 is played back at 48 making the audio LEAD the video!!!
>
> There is no really good solution to this problem that has cost me
> several long days and a few arrows in the rear end. One tool will
> insert blanks in the audio to "lock" it (but as you might imagine
> this does not work well with music!), and another tool will drop
> some video frames every now and then, making the video shorter than
> expected but keeping the audio in sync!
>
> Now the nearly perfect solution would be to multiply the 44 by 12
> to 528 kHz then divide the 528 kHz down by 11 to 48 khz - but that is a
> LOT of processing.
>
>

Fascinating. Why 528?

Ty Ford



-- Ty Ford's equipment reviews, audio samples, rates and other audiocentric
stuff are at www.tyford.com

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