VS X6 audio sync

[weaver]

A new phenomena popped up with the VS X6.
When I render the video in the original format (AVCHD from newest Sony camera) the video on the rendered film remains synchron on the full length. In places where frame blocking etc, happens the audio track has also drops, but on the next correct frame the synchron is correct again.
When I render the same film into different format (HDV or SD for DVD) the audio after the first video instability drops the synchron and never comes back again. On a 40-50 min video the difference was around 1-2 sec.
It does not matter how I render the video direct from the timeline or from the master copy (usually the same format as the original or MPEG optimalized).
In the past with VS 10+, X4 etc. it was not the case.
Unfortunately many video errors are extremely small ( sometimes it is almost impossible to find them on the timeline - or I have to check each cut frame by frame), so the result is seen only after the time consuming rendering.
Is there some recommended practice or experience how to filter out such problems before the rendering procedure?

[Ken Berry]

I am probably more interested in the 'video instability' you mentioned. First off, though, can we assume your Sony films in full progressive mode (i.e. 50P or 50 full frames per second?)

If so, then if you are converting to HDV or DVD, this will be converting to 50i or 25 interleaved frames per second. To do this, VS will literally be throwing away half of the full 50P frames. I am not exactly sure how it handles the audio in such cases, though it could be part of the reason you are having audio out of sync problems.

Where does the 'frame blocking' (pixellation???) occur when you render back to AVCHD? Have you tried turning off SmartRender when doing that render? That usually removes any pixellation problems.

FWIW, I never use the Optimizer function and remain a little suspicious of it since it has given me some poor results in the past -- though I have never used it even once with X6.

[weaver]

Hi Ken

I do not think that the Sony avchd format is progressive. I prefer the much smoother interlaced formats. This means there is nothing to throw away. The file properties say 1920x1080 25 frames/s at cca. 22Mbps speed. I am sure I also set the camera to 50i format.
The pixellation (not really a correct word, I prefer blocking) is not a picture error rather an error when the numbered frames for some reason does not follow correctly each another, in some cases you can check that at the beginning or at the end of the camera clips you have few pictures they are either static (the same in a row - usually 3-4 in a row) or have different order eg, frame #1,#3,#2,#4. i do not know exactly the reason why it happens but since I use HD formats I always experienced such problems (also on my former HDV cameras, as well as on the recent AVCHD and Mp4 cameras). The later are somehow better from this point of view.
On my eralier VS I did not have the optimizer, buth the problems where slso there.
I will try to avoid the Optimizer and I will check the Smart render option ( i do not know, maybe it is one always, I have to find where is this setting. ).
The audio pakets should be locked to the video pakets (some kind of internal timecode - not identical with the known timecodes used on high end cameras). This should care about the synchronisation of the video and audio pakets. For some reason I have a feeling that the downconversion (HDV or SD) removes this portion of the data and this is the reason that the two streams (video and audio) became unlocked to each another,
The main audio problems occur when the cuts in the timeline are not very clean - I can identify them by frame-by-frame stepping over the cuts. If there are the frames OK than there is no problem with the downconverion - rendering.

[lata]

Hi

When you do Share Create Video File—is the option “Same as first Video” available, if so use that, this will use the properties of your video file.
Smart Render……..
The “Create Video File “ window opens, select the Options Button to deselect Smart Render.

Can you provide further details of your video, from the timeline, right click your clip and select properties, what are they.?
Using Alt+PrtSc you can copy the windows content to your clipboard, create a Jpeg image and attach to your post. (file size below 256Kb.)

Otherwise
If “Same as first clip” is available you should be able to copy and paste the details from the Properties panel (Create Video File) window

[weaver]

Hi Trevor

Thank you for your help.

I can do it later today (I am not on my editing computer now).
Practically I am doing exactly that what you are proposing (I edit my video since 2004 on Ulead/Corel).
Just the Smart Render option is new to me (I will check).

For the while there is another bug in the VS X6 and in the integrated MF7.

The same subtitle file created on timeline appears differently on the MF7 screen (also on DVD). (Everytime, when the text is longer than 1 line).
(the character size, or font does not have any influence on this).

On MF6+ everything is correct.

[weaver]

Hi Trevor

Here is the printscreen:
https://www.dropbox.com/s/kkyom6vqinz56 ... ormat1.jpg
Here is the original clip format:
https://www.dropbox.com/s/tm3r9srly9rs0 ... ormat3.jpg
And here is the mastered HD video:
https://www.dropbox.com/s/tm3r9srly9rs0 ... ormat3.jpg
Sorry from my Ipad I cannot insert the pictures.
It says it is full HD with 25 fr/s and format after rendering is m2t
The original video has the same properties, just the name is *. mts

[weaver]

I am trying to insert the pictures also here:

[lata]

Hi

Sorry for the delay in replying to your post
Thanks for the properties details they do look normal / standard sizes and I would have thought should not be causing problems.

In an earlier post I wrote………….

“When you do Share Create Video File—is the option “Same as first Video” available, if so use that, this will use the properties of your video file.
Smart Render……..
The “Create Video File “ window opens, select the Options Button to deselect Smart Render.”

So does using Same as First Video Clip and deselecting Smart Render improve things?

[weaver]

Hi Trevor

thank you very much for your help. I will test it soon.

Unfortunately I am now quite busy and still fighting with the Movie Factory, what is practically unusable in the new VS X6, so I have to burn my DVDs on the old XP computer.
The MF7 integrated in VS X6 handles the subtitles incorrectly. I reported this to Corel, no solution yet.
The MF 6+ on W7 computer has the same issue as the MF7 demo had in 2010 - we also discussed this on this forum. The subtitles stop at about 3 minutes and no solution for that.
That time Corel explained us, that this feature is given by the demo version only.
The same MF 6+ works fine on old W XP and also the subtitles generated by VS X6 are correct there, not like on the built in MF7.

[lata]

Hi

Sorry but I am/was a little confused with your reference to MF 7 and X6.
However I think I now understand, when using Video Studio, Share Create Disc opens the "burner module", is this what you refer to as MF (Movie Factory)

Movie Factory for me is a separate program
A free version MF7SE was provided with X3 after Corels big mistake of changing to the unusable 2010 authoring module.

[weaver]

Hi

Sorry but I am/was a little confused with your reference to MF 7 and X6.
However I think I now understand, when using Video Studio, Share Create Disc opens the "burner module", is this what you refer to as MF (Movie Factory)

Movie Factory for me is a separate program
A free version MF7SE was provided with X3 after Corels big mistake of changing to the unusable 2010 authoring module.

Sorry for the confusion. I was told the the burner module in the VS X6 is the MF7.

I tested the MF7 in 2010 and it failed already that time. The recent version corrupts the subtitles but writes them to the disc.

I have a separate MF6+ which works fine on the old W XP computer.

[erdna]

Your "mico dropouts" is very unusual. Are there other programs running in priority mode at the time of the first rendereing? Futhermore it looks like you have an PS vs TS issue. Mayby VSX6 doesn't recognize/interpret the TS properties of your first defective rendering, causing audio shift because of the absence of correction in PS (program stream) modes. Only TS (transport stream) modes are correctieve and avoids fault propagation.

[weaver]

This is a brand new, practically empty computer, except the Vs X6, MF6+ ,Corel Paint and the antuvirus program (Kaspersky) there is nothing else installed and usually only one program is running + antivirus.
Such drop outs were common also in the past, finally I replaced my computer in the hope of improvement. I also purchased two brand new cameras (AvcHd and Mp4) to the two older HDV cameras, but I still have some unusual effects, for eg. At the beginning or end of the original clips up to 4 frames are static ( not moving), this means I have to cut them away.
I found one of the SD cards causing this error, so I stopped to use it for videos. Other drop outs are ocassional, I have no tools to investigate them.
After first rendering I have usually 1-3 drops in the final HD video (about 30-40 min). Usually I correct those cuts (usually all drop-outs are at video cuts).
The second rendering is usually error free.
When I downgrade the HD video to SD I experience now sync errors in audio. On the SD material I can relative easily find the drop outs, unfortunatelly the audio contunies, so finally at the end of the material the audio track will be out of sync by about 1-2 sec.
I can easily compare it with the original when I place the SD video below the HD wideo on the second video track.

[erdna]

How do you correct the drops (still strange to me) in your rendered HD resuwil? Anyway if your corrected HD frames are incomplete or corrupted, the mpeg2 conversion (rescaled an e-encoded for DVD)) will drop the videoframes.

[weaver]

How do you correct the drops (still strange to me) in your rendered HD resuwil? Anyway if your corrected HD frames are incomplete or corrupted

I go back to the timeline and modify those clips, cuts - move them by 1-2 frames. It is really a precision job, I have to step frame by frame in those areas to find the corrupt frame.
Sometimes I have a feeling that AVCHD has similar problems like in the past the Hi8 had, where one could not edit by any frame, but only at certain frames.
If i need to correct the audio sync in the SD version it is much faster to remove those dropped portions from the SD video, and resync the audio.