View Full Version : Audio Sync issues with Aspect HD


Rich Perry
June 10th, 2008, 08:35 PM
Does anyone have audio sync issues when trying to capture an entire 60 min tape without scene splitting, or longer scenes with scene splitting for that matter?

When using HDlink (Aspect HD) to capture video either via CS3 or standalone (HDlink) the audio is going out of sync. It starts out OK but gets worse several minutes into the scene. I am using a canon HV30, video is captured in 60i, 1440 x 1080. I have also tried scene splitting but still have issues after 10 mins or so. In the past I only ever edited small clips before and not noticed this problem, The audio seems to drift about 4 or 5 seconds out of sync at it's worst. I have tried setting cineform to "desktop playback fast" - no luck. Also tried capturing the video in at 1280x720 as well as the original 1440x1080 - still the same, using :high quality.

As a test I was able to capture an entire 60 min tape without cineform directly into Premier using CS3 device control and captured an mpeg2 file that is perfect, no glitches or problems with audio sync when played back in "classic media player", so why is this only happening when I use Aspect HD?

System type below:

OS: XP Professional
CPU: Intel Quad Core
CPU Speed: 2 GHz - 2.4GHz
Main Memory: DDR2 SDRAM
Memory Amount: >=2GB
Video Drive: Multiple video drives in RAID configuration)
Camera/Deck Model #: Canon HV20
Motherboard Manufacturer: Abit
Motherboard Model #: AB9 QuadGT
Graphics Card Model #: GeForce 6200 TurboCache(TM) (256 MB)
Product Name: Aspect HD
Version #: 5.3.0
NLE Version: Premiere Pro CS3

My PC has a "Raid 0" striped video drive 300 GB, also an independent raid 0 stripped for the C: drive, the page file is on a separate drive. The system is kept uncluttered free and fast. I don't have any issues with scrubbing HD timeline etc. The audio/video is out of sync in cs3 as well as just viewing in "Classic media player" when using cineform intermediate.

Thanks for any help pointers - (see image for HDlink config)

Jose Ortiz
June 11th, 2008, 03:32 PM
Yes I have been experiencing the same problem capturing with HD link the full tape.
I'm a PhD user but I have the same issue.
I can not tell if this has been fixed in the new version.
I will report later.

Rich Perry
June 11th, 2008, 07:29 PM
I am waiting on support - I opened a ticket but it's been a week with very little feedback - not sure if this is the norm or not :)
My short term solution is to make lots of short clips but it's a pain - I don't know if aspect HD ever had the ability to capture a whole 60 min tape in CS3 without sync issues or if it's my system (doubtful as it's pretty fast quad core, 2 GB Ram, multiple raid 0 arrays, bla bla bla).

I am finding other issues with cineform CS3 templates now. (template used below)

General
Editing mode: CineForm HDV 1080i
Timebase: 29.97 fps
Video Settings
Frame size: 1440h 1080v (1.333)
Frame rate: 29.97 frames/second
Pixel Aspect Ratio: HD Anamorphic 1080 (1.333)
Fields: Upper Field First

If adding a .wav or mp3 file to an audio track it plays back fine (with no video). However after adding just 1 video clip (5 sec clip), the audio starts stuttering terribly?. I am not sure if it's all related, but it does not do this with default cs3 hdv templates where audio playback is fine, I am not saying it is cineform, it could be a driver or something else who knows, but without their help I am a bit stuck. I upgraded to the new version of aspect HD and noticed these problems only after the upgrade.

Rich Perry
June 13th, 2008, 08:00 AM
still no response to my 2 tickets open with cineform or this post. Anyone know if my Nvidia 6200 turbo cache graphics card might be the root cause of audio sync loss with cineform avi ?

Alex Raskin
June 15th, 2008, 12:33 PM
Is Aspect HD using more than one core?

Probably not, and then 2.4Ghz is not enough for audio sync.

I had the same issue, when video was captured perfectly without any dropped frames - but audio would go out of sync in minutes.

Upgrading CPU to Core 2 Duo **3Ghz** has rectified the issue, with audio now always in sync on the long runs.

By the way, you can always tell what is going on by looking at the Performance tab - if CPU use is approaching 90% on average, chances are it will also spike and lose audio sync then.

Rich Perry
June 16th, 2008, 05:07 AM
The processesor is actually a quad core q6600 - this should be powerful enough should it not? CPU activity never seems that busy during capture.

Jake Segraves
June 16th, 2008, 11:24 AM
I'm looking at your tickets now. We'll try to get things squared away through support.

As Alex suggested. Load the task manager and check the CPU usage during playback. When the audio stuttering starts, is there any spikes in the CPU usage? Please let me know your results on the support ticket for this issue.

Regarding capturing full tapes and having the audio go out of sync, this will happen if you don't use the 'scene split' or 'detect scenes' options. Its simply a limitation of the way our capture components work. When we get the mpeg sample off the tape, we need the audio video together and when we split scenes we're able to read that data accurately. But when capturing that whole tape it becomes ambigous at the points where there actually is scene change. Over time, that amibuity adds up and causes the sync loss.

What you could TRY (no guarantees), is to take your mpeg file that you captured using premiere's native hdv modes, and convert it to a cineform file. There's a chance this still might not work though.

So, long story short, our recommendation is still to use the 'scene split' options in both HDlink and Premiere.

As an editor, personally I find that to be a more beneficial method anywas. I'm not a big fan of super long clips. I like them broken up into smaller pieces so I can find things easier. But that's just me.

Tim Bucklin
June 16th, 2008, 12:36 PM
Regarding capturing full tapes and having the audio go out of sync, this will happen if you don't use the 'scene split' or 'detect scenes' options. Its simply a limitation of the way our capture components work. When we get the mpeg sample off the tape, we need the audio video together and when we split scenes we're able to read that data accurately. But when capturing that whole tape it becomes ambigous at the points where there actually is scene change. Over time, that amibuity adds up and causes the sync loss.


To elaborate on what Jake's saying, when you start and stop recording, the cameras don't reliably end the audio and video portions of the MPEG stream correctly. For some Sony cameras, you may have the option of "quick record" in your camera settings. When this is enabled, you'll get out-of-sync audio on long captures over multiple clips. When it's disabled, it makes sure to terminate the MPEG streams properly so that you don't get the audio wander. The scene split function in HD Link forces a re-sync at the start of each clip.

Rich Perry
June 21st, 2008, 01:30 AM
Thanks for the tips guys,
We did a buch of testing and Jake was very helpful. At this point though I am reinstalling my O/S as a second dual boot O/S to another logical drive on the same stripped raid 0 array) as I have other issues with playback using the cineform templates (HDV 60i) 1440h 1080v (although premier templates are fime). The audio stutters badly with the cineform templates, but we have determined that the hardware is good and this is a new problem, so a re-install at this point seems to only logical step as I have tried just about everything else. I will let you know how it works out - thx.