Audio sync issue...

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maddrummer3301
Posts: 2507
Joined: Fri Dec 10, 2004 10:24 pm
Location: US

Post by maddrummer3301 »

Hi,

In reference to the audio sync problems:
How are the origiinal Mpeg2 files being recorded?
Within VS8 or using an external program(s).
Are the original files using 16bit 48khz audio or different?

Could someone please post some information on how the files
are being recorded?
What the recording properties are versus what VS8 says they are?

MD


frankhad:
48C = 118.4 F
Had that problem on a 3.2 P4 800FSB with 1 Meg on die cache.
These processors run hot.
Asus has a real-time monitoring utility to shutdown pc at a preset temp.
Also in the BIOS. Also a utility to control the cpu fan speed.

I installed better heat-sink compound between the processor and the
heatsink. Also used a super-cooler (heatsink with squirrel-cage fan).
When the thermistors inside of the cpu signal the cpu is to hot that
triggers the power supply to shutdown. On some units one has to
unplug the 120volt power cord or toggle the supply on/off to reset the
power supply to boot again.

Hope this helps,

MD
GeorgeW
Posts: 2595
Joined: Sat Dec 11, 2004 5:25 am

audio

Post by GeorgeW »

make sure audio stays the same throughout the process -- for DVD you will need it to be 48khz, and alot of times people capture at 44.1khz or other sampling rates.

In some cases, people have had better results using elementary streams -- create just an audio track that is already dvd compliant, and use that in your project along with the video stream. Make sure both are the exact same length.
George
aconnell

Post by aconnell »

I'm using my digi Sony HandiCam and capturing the video using a firewire card and the Roxio Easy Media Creator v7 OR ULead Video Studio 8. So no real device to capture other than my digicam.
thecoalman

Post by thecoalman »

aconnell wrote:I'm using my digi Sony HandiCam and capturing the video using a firewire card and the Roxio Easy Media Creator v7 OR ULead Video Studio 8. So no real device to capture other than my digicam.

Yeaaaaaa, that's the perfect format. Capture it as DV1 that's it. At least that's been my experience with Ulead, Your going to need about 14 gigs for an hour. You can use any software you want to capture it's irrelevant. Just make sure your using DV1 as the format.
aconnell

Post by aconnell »

Can't tell if you're being sarcastic with me, but so far that's what I'm doing. Yes, a 60m video is results in a huge AVI file, but it works and there is no sync issue. Do you suggest a different format to capture in?

I'm a bit of a newbie with the video/audio stuff... I'm a .net developer, but just recently got into all this digital video stuff (bit rates, capture, encoding, etc).
thecoalman

Post by thecoalman »

You don't capture DV footage, you transfer it. :D It's lossless transfer, When you plug the cam you need to choose the capture plug in I think? Choose DV, you are in fact copying the file from your cam to HD.

You do realise DV and AVI are one in the same. It's DV-AVI...there's other kinds of AVI, I'm guessing you were capturing to a uncompressed one? maybe 60gigs a hour? Or do we have a miscommunication here?
jwarner

Post by jwarner »

In my (humble) opinion, uncompressed video makes no more sense than uncompressed digital photos - that's why .bmp format is rarely used by digital cameras anymore.

Why would you want to fill up your hard drive with information that says "a blue bit here, a blue bit here, a blue bit here, etc. etc." when it is far more effective to say, the next 2 million bits are blue.

That's why all digital camera's now use .jpg format.

Encoding video needs much more processing obviously and early digital video cameras couldn't do it effectively so opted for an uncompressed format. Newer cameras don't have that problem so use compression (MPEG2 or MPEG4). Soon, I expect, all video cameras will record in MPEG4 format directly to flash media so there will be more more mechanical nonsense to deal with for storage.

Just because Ulead seems to have a problem handling MPEG's doesn't seem sufficient reason in my mind to save a bunch of storage-hungry AVI's. Especially since, if your eventual goal is to burn a DVD, it will have to end up as an MPEG2 at some point!

But, that's just my opinion...
maddrummer3301
Posts: 2507
Joined: Fri Dec 10, 2004 10:24 pm
Location: US

Post by maddrummer3301 »

John,

>a blue bit here, a blue bit here, a blue bit here, etc. etc." when it is far
>more effective to say, the next 2 million bits are blue.

For your information:
You are correct and that is exactly what the DV codec is.
the DV codec is a COMPRESSED Codec.
That is what the DV codec is doing already.

Uncompressed video I think is at least 1gig a minute.
So you can see why the DV codec is very effective.
You wouldn't even want to try uncompressing a dv file.
There isn't much difference using the dv codec because it's doing
the compression as you said would make sense.
DV video is frame by frame time stamped video.

MD
frankhad

Post by frankhad »

thecoalman wrote:I think there's a bug in the program....
Especially considering the fact that this has suddenly appeared, apparently this wasn't an issue before? That's just specualtion on my part though.
I no longer think it's speculation on anyone's part.

FWIW, I just completed processing the 2-hr movie mentioned in my last post. And, wonder of wonders, I was able to edit, author and burn a useable, viewable DVD WITH NO SYNC PROBLEMS!

Sadly, it was not done in UVS8 but rather in UVS7.

Yesterday I completely (for the second time) uninstalled and removed all references to VideoStudio on my computer. Since my version of UVS8 is an upgrade, it needs a copy of version 7 on my system before it will allow installation of the upgrade. When I installed version 7, and before I began the UVS8 upgrade, it occurred to me it might not be a bad idea to try to create the DVD burn that has eluded me these past several days. And it worked. I had not installed the 7.01 patch. Just installed the USV7-ESD version as it originally came.
The point is why bash your head against the wall. Try a different route. If it's happening to so many then why fight it?
Complain if that's the case
All throughout this process, which has gone on now, almost non-stop for several days, I kept wanting to continue on in order to eliminate any possibility it was I (and not the program) who was creating the problem. In the back of my mind there was always the notion that UVS8 might indeed have some problems. But I wanted to keep on keeping on just to make sure it wasn't something I was doing. After all, isn't that what Ulead Customer/Technical Support would have suggested were I to make contact at any earlier stage?

I'm not completely finished this learning/testing journey I've undertaken. Next, I want to process a 2-hr clip in which commercial ads have been extracted from within the clip. At this stage, however, it certainly does appear UVS8 has problems serious enough to keep me (and seemingly others) from accomplishing even the simplest of burning projects.

I do intend to complain to Ulead.

In the final analysis, however, it made no difference that the clip was captured in MPEG and not AVI.

f
jwarner

Post by jwarner »

maddrummer3301 wrote: Uncompressed video I think is at least 1gig a minute.MD
An uncompressed AVI Video file at 640 X 480 takes 900kb per frame. At 30 fps 24bit color that works out to 26.37 MB per second or 1.582 GB per minute.
thecoalman

Post by thecoalman »

jwarner wrote:
maddrummer3301 wrote: Uncompressed video I think is at least 1gig a minute.MD
An uncompressed AVI Video file at 640 X 480 takes 900kb per frame. At 30 fps 24bit color that works out to 26.37 MB per second or 1.582 GB per minute.
It depends on the type of AVI used. AVI is a generic file extension that just means it contains video. What's important is the compression codec used to create it. DV-AVI is about 14 gigs per hour, another commonly used format Huffy-AVI if I remeber correctly is about 20 gigs per hour. "Uncompressed" AVI using the MS codec is about 50-60? I forget I don't use it. The reason for the quote is because even uncompressed is compressed, the file sizes of a truly uncompressed video would exceed that of the capacity of current large drives.
Last edited by thecoalman on Mon Feb 14, 2005 1:31 pm, edited 1 time in total.
thecoalman

Post by thecoalman »

jwarner wrote:In my (humble) .

Why would you want to fill up your hard drive with information that says "a blue bit here, a blue bit here, a blue bit here, etc. etc." when it is far more effective to say, the next 2 million bits are blue.
This is similar to how video is compressed but that's not exacly how it works, it varies according to the compression method but basically a .jpg compresses by grouping like colors together. It in affect softens the image. With a large image a jpg compressed at 90% you would never know the difference between a bmp and a jpg unless you zoom in. Here's an example, the image in the left pane is a image from 3 megapixel camera, if notice the slider it's set at 90% compression which produces an image very near the original. If you look in the right pane you will see the image colors have changed. Where the quality loss comes in is when you keep recompressing, eventually all the detail is going to be loss and if you keep recompessing the affect is no longer a softening affect but produces blocks of color. This is the same thing as reencoding a mpeg, evertime you reencode you lose detail but it's a little more complicated than that....

Image

Here's an example of the same image compressed at 20%, the biggest thing to note here is huge block of a single color in the upper center part of the image in the right pane.:

Image

Where the issue comes in with MPEG is the way it's constucted, some frames take data from the previous frames which is one of the reasons it compresses so good, when cut one of these frames it needs to be reconstructed by the editor. This sometimes leads to audio sync when you cut on these frames....why I don't know. It really depends on the editor.

You can learn more about the differences between AVI and Mpeg here: http://www.digitalfaq.com/capture/avivsmpeg.htm

Encoding video needs much more processing obviously and early digital video cameras couldn't do it effectively so opted for an uncompressed format. Newer cameras don't have that problem so use compression (MPEG2 or MPEG4). Soon, I expect, all video cameras will record in MPEG4 format directly to flash media so there will be more more mechanical nonsense to deal with for storage.


I'll disagree with the mpeg4 part, mpeg4 was created to be a highly compressed format it to has the same issues as using MPEG2 as a source. The reason tape is used is because of it's storage capacity, you can only fit 20 minutes of DV-AVI on a DVD in addition to the fact of the speeds the DVD would need to be spun to record it, 16x drives might do it but I'm not sure. Remember though there is no difference between the file on tape compared to the one on DVD or any other media. If they wanted to they could record mpeg to tape as well but don't because there is no reason too. Shortly you will see another format with high capacity, blu-ray, flash whatever. They will still use a less compressed format though. And to further that you will still probably only get 1 hour since the new high definition TV's and cam's are coming on the market. :?
Just because Ulead seems to have a problem handling MPEG's doesn't seem sufficient reason in my mind to save a bunch of storage-hungry AVI's. Especially since, if your eventual goal is to burn a DVD, it will have to end up as an MPEG2 at some point!
Yes it aapears there is bug somewhere but VS8 isn't the only editor that has issues with mpeg. My curiosity is whether it's just prevalent when using mpeg or if AVI has the same issues too. I haven't seen anyone post that the same issue exists using AVI as source? Anyone?

Again MPEG is not for editing for more reasons that the audio sync ones. An extreme example but here's the difference http://phpbb.ulead.com.tw/EN/viewtopic.php?t=1428 :

3000CBR MPEG encoded from a DV-AVI, Lot's of macroblocking:
Image

3000CBR MPEG encoded from the 8000CBR MPEG, a real lot of macroblocking:
Image[/list]
Last edited by thecoalman on Mon Feb 14, 2005 1:43 pm, edited 9 times in total.
aconnell

Post by aconnell »

thecoalman wrote:You don't capture DV footage, you transfer it. :D It's lossless transfer, When you plug the cam you need to choose the capture plug in I think? Choose DV, you are in fact copying the file from your cam to HD.

You do realise DV and AVI are one in the same. It's DV-AVI...there's other kinds of AVI, I'm guessing you were capturing to a uncompressed one? maybe 60gigs a hour? Or do we have a miscommunication here?
Actually I didn't realize that the DV-AVI was uncompressed. I need to go back and check to see how I can tell UVS8 or EMC7 how to capture compressed AVI... correct?
FWIW, I just completed processing the 2-hr movie mentioned in my last post. And, wonder of wonders, I was able to edit, author and burn a useable, viewable DVD WITH NO SYNC PROBLEMS!

Sadly, it was not done in UVS8 but rather in UVS7.
Hopefully ULead will recognize this and work to remedy this issue.
thecoalman

Post by thecoalman »

Actually I didn't realize that the DV-AVI was uncompressed. I need to go back and check to see how I can tell UVS8 or EMC7 how to capture compressed AVI... correct?
It is compressed just not as much as mpeg. See the post above by maddrummer. I'm looking at VS7 here but you have a choice as your format to capture to. MPEG, DVD, VCD AVI, DV....etc. Pick DV, as I stated it's DV-AVI, it's an exact copy of the file on your cam, it's as if you went into your HD and copied a file from one folder to another. The only differenc is your HD has to be able to write the info fast enough which generally isn't an issue.

That information pertains only to Digital cams.
MDK15

Post by MDK15 »

Apologies if this has been posted before.

I'm using a Dvico Fusion MPEG2 capture card and I capture as MPEG2. It works fine when I play things with Windows Media.

However, when I burn it into DVD using Ulead Video Studio 7SE and play the DVD on a standalone DVD player the audio is out of sync.

Any help would be much appreciated.

Many thanks.
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