Hi, I captuered a 44.1kHz soundtrack from a Laserdisc and want to replace te AC3 soundtrack of a DVD of the same video . DVD does not accept 44.1kHz pcm tracks, and no other video container seems accepting it. So te only soultion seems to upsample to 48kHz. I guess this wil cause a loss; the original track was at 44.1kHz and 16 bits resolution, te audio card I used captured it at 32bits, is this the only soultion? I was also thinking to use wma lossless encoded with windows media encoder in wma 9.2 lossless and mux all to mkv, could tis be better?

Using a good resampler to resample from 44.1kHz to 48kHz will not cause a significant loss in quality. Most encoding applications have an OK one built in, but feel free to look at r8brain, Cool Edit, Audacity, SSRC or one of the many other good quality resamplers available.

Audacity (at least for win32) uses libresample (which is of inferior quality than some other resamplers)
http://audacityteam.org/wiki/index.php?title=Libresample

When recording digital audio, you shouldn't "capture" the audio in a higher bit depth than it really is. The whole point of digital recording is to simply move the data from point A to point B without loss, so you should just leave it at 16 bits in this case. This is very different than recording analog audio, where extra bits help get the truest *representation* of the sound (since the resolution of analog is theoretically infinite).

At least I assume you're doing a true digital transfer here - with coaxial or optical cable?

Anyway, you really have two options with the sample rate. I always transfer laserdisc audio at the original 44K and resample to 48K with Adobe Audition in post.

However, letting your sound card do the resampling to 48K on-the-fly may also be a viable option, depending on the conversion quality. But then you won't have an original 44K copy, which I like to keep for archival purposes.

Using any lossless codec is fine (I prefer FLAC), but in the end you're obviously going to need a 48/16 WAV file for the DVD.