LPCM versus original AC3 audio when archiving AVCHD? at DVinfo.net

Drew Wallner · December 22nd, 2012, 09:17 PM

I have a very large collection of home video clips which, with help from ClipWrap, are now stored in individual .mov containers instead of dozens of unwieldy AVCHD disk images. Thank you for that! It's difficult to overstate what having my content broken out this way has done for my sanity (and ability to cull bad clips to reduce the size of my backups significantly).

When clipping all my media into Quicktime files, I changed the default ClipWrap setting to convert their native audio to LPCM (unchecked it). I figured I'd rather keep the original AC3 for now, and worry about whether I want to downmix any of it or convert it to a less compressed format in the future. I don't appear to have any problems loading these clips into any of the NLEs that I currently use.

My question is this, before I go ahead and abandon my original AVCHD disk images...can anyone think of a reason I would regret this someday? It doesn't seem like a big deal, but I just wanted a "gut check" in case I was missing something obvious. It seems to me that since I could always create LPCM (or anything else) from the AC3 at a later date, for the time being it makes sense to just stick with the audio in a more "original" and more tightly compressed state.

Thoughts and feedback welcome!

Colin McFadden · December 22nd, 2012, 10:29 PM

The only reason I'd be a little cautious is because Apple's support of AC3 on OSX has been a bit hit or miss - they've never officially documented the types of ac3 bitstreams they handle, so they might break something down the line within their apps.

In general though, I wouldn't worry - worst case, you could use an app like FFMpeg to convert the ac3 to lpcm down the line.

-Colin

December 22nd, 2012, 09:17 PM	#1
Drew Wallner New Boot Join Date: Apr 2009 Location: Kailua, HI Posts: 24	LPCM versus original AC3 audio when archiving AVCHD? I have a very large collection of home video clips which, with help from ClipWrap, are now stored in individual .mov containers instead of dozens of unwieldy AVCHD disk images. Thank you for that! It's difficult to overstate what having my content broken out this way has done for my sanity (and ability to cull bad clips to reduce the size of my backups significantly). When clipping all my media into Quicktime files, I changed the default ClipWrap setting to convert their native audio to LPCM (unchecked it). I figured I'd rather keep the original AC3 for now, and worry about whether I want to downmix any of it or convert it to a less compressed format in the future. I don't appear to have any problems loading these clips into any of the NLEs that I currently use. My question is this, before I go ahead and abandon my original AVCHD disk images...can anyone think of a reason I would regret this someday? It doesn't seem like a big deal, but I just wanted a "gut check" in case I was missing something obvious. It seems to me that since I could always create LPCM (or anything else) from the AC3 at a later date, for the time being it makes sense to just stick with the audio in a more "original" and more tightly compressed state. Thoughts and feedback welcome!

December 22nd, 2012, 10:29 PM	#2
Colin McFadden Sponsor: divergent media Join Date: Jun 2004 Location: St. Paul, MN Posts: 201	Re: LPCM versus original AC3 audio when archiving AVCHD? The only reason I'd be a little cautious is because Apple's support of AC3 on OSX has been a bit hit or miss - they've never officially documented the types of ac3 bitstreams they handle, so they might break something down the line within their apps. In general though, I wouldn't worry - worst case, you could use an app like FFMpeg to convert the ac3 to lpcm down the line. -Colin __________________ Divergent Media Support www.divergentmedia.com