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darryl
01-21-2012, 10:49 PM
Having always been interested and involved in music, I watch a lot of Yootoob videos. It irks me that seldom are the audio and video tracks synchronized. Does anybody know of a program that could allow a person to do this on the fly?

What I'm thinking would be nice is if a knob shows up on the screen which you could just turn with the mouse, and a number would show up as you rotate it. Once you have the synchronization dialled in, the number would give you the reference for the next time you played it. Something like that anyway.

There are a couple of programs I could use, but that would mean downloading the video intact, then being able to open it in the program and selectively delay the fast part, or move the slow part ahead, save that result, then choose it from a folder and replay it. That would mean loading each video onto the hard drive, then being free to play with it. Can this even be done?

+ or - Zero
01-22-2012, 04:57 AM
Interesting, that is a problem I've never seen (well noticed anyway). I have not used any Microsoft products or stuff from that food chain for years so I have no idea on that side of things, but I think this would be difficult to achieve in a real time stream without some serious processing power --think Cray or equivalent (maybe a slight exaggeration, but you get the idea).

I could also be very wrong, maybe there is such a thing. I'd be interested in any info on such a program, so maybe some one will come along with better info.

As to loading the stream to your hard drive it does that anyway --they often don't want you to know this --copyright stupidity, etc. But once you have the file in a way that is under your control then of course you can sync it (easy and free with *Nix, no idea about the Windows side) --someone probably sells a native *doze program, or has ported a FLOSS program to do it on a *doze system.

darryl
01-22-2012, 01:02 PM
Offhand, it seems like it would be relatively easy to create a delay in the playing of either the audio or the video track. If it's loading to the drive anyway, the information is there. You could open the video track in one instance of the player, then the audio in another. If you started both playing at the same time, they would be in sync, or out of sync, as they were recorded or delivered in the first place. You could hit pause/play, etc of one of the tracks until they were synced properly. Admittedly this is a crude way of adjusting things, but it shows the potential is there to sync the tracks without requiring a lot of horsepower.

If both tracks were simply streamed without recording anything to the drive, then you could still address the issue by having the early track go through a delay circuit. It would be recorded and played up to say several seconds later, even if the protocall was to allow streaming only and no write to drive. The delayed track could still be erased the moment it was actually played, so that should still satisfy the legalities.

I know that if I could find both tracks on my drive, I could use a program to sync them up. I've seen more than one program that can do this- not as easily as I'd like, but the programs are fat in that they can do a lot more than just adjust the position of the track in time relative to another track.

Am I asking too much to have the audio and video play in tune? I sure don't think so-

Black Forest
01-22-2012, 01:19 PM
You need to load the video into a editing program to sync up the audio.

You all know of the clapper you see when the director yells "action" on a film set. That clapper is actually for syncing up the audio.

Darryl the audio and video are in one file when you download. They are not separate.

+ or - Zero
01-22-2012, 01:32 PM
Well first don't worry much about the legalities because the net and your, or my, computer simply don't work if you try to abide by copyright law. I'm not making that up or joking.

Second, yes you should be able to watch video in sync with the sound.

Third, everything you ever see on your computer is stored in one way or another before it's rendered on your screen, so what they pass off as 'streaming' really isn't. All of it, the net, the way a computer works, electronic gadgets in total, are just a big slight of hand trick based on the fact that electronics are very fast compared to human senses.

Anyway what you are talking about doing is indeed possible --I can do that easily with my *Nix system, but I am syncing from a file --but then if it passes through my computer I have control of the file... it's the nature of free (as in software freedom, not price) systems.

You too can do the same (I'm guessing you use some flavor of Windows?), but it will no doubt be more difficult, unless someone has written a program to do that on Windows. They may have, I just wouldn't know what it is. Sorry I just don't do Windows.

But I do sympathize with the problem --one's computer should do the tasks it was designed for, and do them well. Which, unfortunately is where you (and to a degree my) problems come from --there are people that in order to protect IP (imaginary property) attempt to defeat the very thing a computer was made to do --copy files, with speed and accuracy, and to allow you to manipulate those files in a useful way.

While that isn't any help for your direct problem it is the cause. Understanding the cause may help you find a solution. My best notion would be to find a way (there are lots of ways) to simply get the file you want in a form that is not crippled --you may then do with it as you please... like actually watch and hear it in a normal fashion.

Such is the state of the world today. Did I just advise you to break a law? Probably.

+ or - Zero
01-22-2012, 01:49 PM
You need to load the video into a editing program to sync up the audio.

You all know of the clapper you see when the director yells "action" on a film set. That clapper is actually for syncing up the audio.

Darryl the audio and video are in one file when you download. They are not separate.

Actually they usually are separate, but they come in the same container. For example an ".avi" file is actually a container for any one of many methods of containing a set of audio and video files.

see: http://en.wikipedia.org/wiki/Digital_container_format for an overview.

So yes to the average end user it appears to be all mixed in one file, but it really is just all in one envelope.

darryl
01-22-2012, 04:43 PM
It appears that for the most part, the video is ahead of the audio. Maybe Yootoob has a solution for the end viewer-

aboard_epsilon
01-22-2012, 04:54 PM
VLC player has so a device built in ..

top of the player

tools... then....
track syncronisation

you then alter the audio.... retard or advance in fine incriments 0f 0.001 seconds

VLC player is free to download ..the version that i have is 1.1.11

all the best.markj

+ or - Zero
01-22-2012, 06:30 PM
VLC player has so a device built in ..

top of the player

tools... then....
track syncronisation

you then alter the audio.... retard or advance in fine incriments 0f 0.001 seconds

VLC player is free to download ..the version that i have is 1.1.11

all the best.markj

VLC is a great program, I use it often on *Nix and I knew there is a Windows version, but irrespective of the platform, does VLC correct the incoming from the internet stream? I know it does from a file or in a stream that VLC it's self is being used to stream, but I've never had occasion to try sync with any internet stream, such as utube (just lucky I guess in that they are always --so far, in sync for me).

All I noticed on Google was fixing from a file or in a VLC streaming file --but I didn't (couldn't) read every hit, so I figured I could just ask you.

macona
01-22-2012, 06:37 PM
There may be another issue. What are you listening though? I have to use a 50ms delay in my Onkyo receiver to get voice to match up right through HDMI.

aboard_epsilon
01-22-2012, 07:05 PM
VLC is a great program, I use it often on *Nix and I knew there is a Windows version, but irrespective of the platform, does VLC correct the incoming from the internet stream? I know it does from a file or in a stream that VLC it's self is being used to stream, but I've never had occasion to try sync with any internet stream, such as utube (just lucky I guess in that they are always --so far, in sync for me).

All I noticed on Google was fixing from a file or in a VLC streaming file --but I didn't (couldn't) read every hit, so I figured I could just ask you.

Never tried it with streaming ...youtube has it's own flash player ..

So to correct them you'd have to download them

Firefox has a downloader for you tube..that puts the button right under the player. ...most files are flp....and it works perfectly

all the youtube downloader progs Ive tried for internet explorer ..faulted and didn't work in the past..good twelve months since i tried....think they were separate programs that you had to paste the youtube url into.

When you get the file downloaded, there are other programs that convert them back to what they were before youtube converted them to flp.

so you may have to download ...convert ..then play...cant remember ....its a while ..it may be a case of just re-nameing them mpg avi etc

you cant stream youtube vids into vlc player as far as i know...its a good twelve months since i messed about like this ..and things change all the time.

all the best.markj

+ or - Zero
01-22-2012, 07:17 PM
There may be another issue. What are you listening though? I have to use a 50ms delay in my Onkyo receiver to get voice to match up right through HDMI.


Good point, macona.
Out of curiosity, are you delaying video to match the audio or the other way around? (I don't know if an Onkyo receiver can delay video --I know they are nice units)

I ask because the HDMI spec is it's self one of those IP protection schemes, and as such it interests me when people need to correct something that should not actually need correcting (that may not be the case, in your case --but it seems it only happens to you via the HDMI interface?).

+ or - Zero
01-22-2012, 07:42 PM
Thanks markj
I thought that might be the case --I can cause VLC to be the default player for my web browser, but even so it is actually playing from the file on the drive or from ram not some magic way from the net stream. All players, or web browsers with imbedded players, are working from a stored file (sometimes the buffer is just in ram but that's still working from a stored file on your computer --just not as permanently stored, unless you make it so).

Using HTML5 and webm is a really good way to watch youtube, if the video is in webm (I think most are now), so no flash and easy download.

dp
01-22-2012, 08:00 PM
My wife is in a womens' choir. I do the audio recording and another fellow does the video. I record the entire concert in one long stream and he shoots video when the singing starts. In addition to putting the room back into the recording I have to align the sound track and the video track. But wait - there's more. I use two digitizers for left and right and have to sync those, too. Not having a clap board I have to focus on the director and the front row of singers. Then there's the problem of the clock speeds in the three digital devices. When everything is aligned at the beginning the end sections will have drifted a few miliseconds - enough to put "ambiance" (echo) into the recording.

So the way I do things is to select a song, move to the beginning, expand the tracks in the digital mixer, and look for a common signature in all 4 tracks or at least in both of the stereo track pairs - usually comes from the drummer but can be a cough in the choir or audience. Then I align the tracks. I jump to the end and do the same except in this case I have to change the sample rate of one track or the other to bring the alignment in.

In this example somebody dropped something just at the beginning so it was a no brainer :) http://www.youtube.com/watch?v=Z8OqL0WkMZ8 (from the move "Sister Act".)

And after you do all that and get the vid and audio tracks aligned, youtube conversion will sometimes clobber the audio - in the link about the audio sounds "wet" like an mp3 compressed recording.

+ or - Zero
01-22-2012, 08:00 PM
It appears that for the most part, the video is ahead of the audio. Maybe Yootoob has a solution for the end viewer-

Inadvertently I think I stumbled on to a possible answer for you. I was replying to a post by markj (above) and realized that I use a browser capable of HTML5 and webm, which may be why this has not been a problem for me.

A real 'duh' moment for me...

So, you might try that also (not the duh moment, just the web browser...). There are a couple of options, maybe several for Windows, I don't know but Google "youtube webm" and I'll wager several will be presented that you might try. Like Googles own browser, or maybe Opera, possibly others. I'd be very interested in knowing if doing so cures your problem.