INTERACT FORUM

More => Old Versions => JRiver Media Center 19 for Windows => Topic started by: sema on March 09, 2014, 04:23:04 pm

Title: Lip sync for Netflix (etc.)
Post by: sema on March 09, 2014, 04:23:04 pm
Hi everyone,

i am using Acourate-generated room-correction filters in MC 19's convolution engine. The result is great and I don't want to miss this sound anymore. However, convolution causes considerable latency. While this isn't a problem with music, it is with movies, bringing video and audio totally out of sync. So far I have used DVD and BluRay movies with JRiver and there the lip-sync function works well to correct the issue.

I also use Netflix, though. I haven't tried Netflix with JRiver at all so far, but maybe you guys can give me a heads-up: Is there any way to get lip-sync of Netflix movies with JRiver when I use convolution? And for Youtube?

If not: Is there any way, with any external software maybe, to delay video output so I could manually restore lip-sync?

Bests
Simon
Title: Re: Lip sync for Netflix (etc.)
Post by: mwillems on March 10, 2014, 08:06:19 am
Hi everyone,

i am using Acourate-generated room-correction filters in MC 19's convolution engine. The result is great and I don't want to miss this sound anymore. However, convolution causes considerable latency. While this isn't a problem with music, it is with movies, bringing video and audio totally out of sync. So far I have used DVD and BluRay movies with JRiver and there the lip-sync function works well to correct the issue.

I also use Netflix, though. I haven't tried Netflix with JRiver at all so far, but maybe you guys can give me a heads-up: Is there any way to get lip-sync of Netflix movies with JRiver when I use convolution? And for Youtube?

If not: Is there any way, with any external software maybe, to delay video output so I could manually restore lip-sync?

Bests
Simon

I'm not aware of anyway to fix the lipsync issue with web content on the "back end" (i.e. at play time).  If you play a youtube video in JRiver and choose the menu option to play it in JRiver it might work (but youtube's interface doesn't always allow that).

As for Netflix, they in particular don't like to play ball.  Netflix always outputs to the system default output device bypassing JRiver's audio chain, so the only way to get netflix sound in JRiver is through loopback or ASIO line in.  Which means at that point there's no way to re-sync the video and audio. 

What many folks here do is create a shorter set of convolution filters for use with web media, and then use JRiver's zones and zoneswitch to route audio to the appropriate filter bank (Audiolense offers a "minimum latency" filter, and I believe Acourate offers an option to restrict taps or filter length as well).  See this thread for more details and some helpful links: http://yabb.jriver.com/interact/index.php?topic=87579.0.   

If you can get your total latency below 20ms, lipsync should work pretty well.  Because system and soundcard latency ordinarily eats up a few ms, that means you probably want to try and create convolution filters in the 15ms length range (depending on the algorithm, probably around 1200 taps at 44.1 KHz)
Title: Re: Lip sync for Netflix (etc.)
Post by: sema on March 12, 2014, 01:30:51 pm
Many thanks for the advice! Yes I think the filter length in Acourate can be limited and I will try that when I have time.