Audio/Video Sync Issue VSX9

[binky911]

Corel Video Studio x9 has a serious bug where the audio/video becomes out of sync when using Smart Render with AVCHD video. I was able to reproduce the problem on both Windows 7 and Windows 10. It appears that the shift occurs at the point where two clips are joined together, and becomes increasingly worse the more clips you have. I created a 50 minute video with 70 clips and by the end of the video the audio was almost a second out of sync. When Smart Render is turned off, the sync issue goes away, but the render time takes more than 10x longer. I have been using VideoStudio x5 for the past 4 years and used VideoStudio x2 for 4 years before that, and never had any problems with Smart Render.

I created a help desk ticket with Corel customer support and they did help me narrow the problem down to a Smart Render issue. After that they wanted to close the ticket, but I told them turning off Smart Render was unacceptable due to the long render times. They gave me the run around saying my machine was too old to work properly with the newly optimized Smart Render in x9, and suggested I buy a new machine. Since I have access to newer AMD and Intel machines, I rendered the same video on both of them and it produced the same output file with the same audio/video sync issue. So much for a hardware problem. After providing them with these results, they have decided to ignore me and no longer respond to my emails. I simply wanted them to acknowledge the issue and let me know when to expect a fix, but I can only assume they have no intention of fixing it.

[lata]

Hi bink911

Out of interest what are the full properties of your AVCHD video files, and what template are you using to render the project.

Also what are your Project Properties?
At the point where the clips are joined have you use any transitions, if so which ones.

I assume Corel Support have also asked.

[binky911]

Here are the properties of the input video clip.

File format: NTSC HDMV

Video
Video type: H.264 Video, Upper Field First
Total frames: 1,065
Attributes: 24 bits, 1920 x 1080, 16:9
Frame rate: 29.970 frames/sec
Data rate: Variable bit rate (Max. 16000 kbps)

Audio
Audio type: Dolby Digital Audio
Total samples: 1,705,706
Attributes: 48000 Hz
Layer: None
Bit rate: 256 kbps

Here are the steps to reproduce the problem.

1) Import all 70 media clips.
2) Add them to the video track.
3) Select the "Share" tab.
4) Check the "Same as first video clip" option.
5) Make sure "Smart Render" is enabled. It's checked by default.
6) Choose a location and name for the video.
7) Select the "Start" button.

[lata]

Hi

I ran a similar test 53 MTS files recorded with Panasonic camcorder.
Added to timeline with crossfade transition on each clip.
Total length of project 13 minutes.

I also added a sound clip at various intervals, a door bell sound, also marking the position with a CuePoint.

Then rendered “Same as First Clip” using Smart Render
Added new video to overlay track to compare wave form using Sound Mixer
No real problems, there was less than I frame difference in the audio streams.

I’ll try again without transitions………..

The properties of my video although Pal is very similar to yours.

[binky911]

Hi Lata,
Thanks for trying to reproduce the problem. Did you try without transitions? I just tried another test with 50 copies of a 14 second clip, and the audio/video is clearly out of sync by the end of the 12 minute video. I'm starting to wonder if it could be my camcorder. I have a Canon Vixia HF100 that came out in 2008. Any thoughts as to whether this could be the problem? I still find it strange that VideoStudio x5 works just fine, but the latest version doesn't. Do you know where I can download some AVCHD footage on the web so I can test this theory?

Thanks.

[lata]

Hi

I did indeed run more tests but the same audio change is less than one frame, just a small shift, apologies for not replying.

I can upload a few samples for you to try, none of my video has “lip sync” all are scene recordings, so I rely on the audio wave form to check sync.

As you know they are quite large but will sort out a couple of hundred MB

As you think it may be your files, If you could do the same I can test your files.

[binky911]

Thanks for running more tests. Please upload your videos for me to try. I downloaded a clip from the web and it produces the same audio/video sync issue, so this rules out a problem with my camcorder. The clip is 29s long and is only 15MB so I can easily upload it. I can also upload the final video that joins this clip 50x, but it is 742MB. By the end of the video the audio is nearly a second behind the video. How do I upload the videos? The format of this clip is as follows:

NTSC drop frame (29.97 fps)
MPEG-4 Files
24 bits, 1920 x 1080, 29.97 fps
Frame-based
H.264 High Profile Video: 4022 Kbps, 16:9
44100 Hz, 16 Bit, Stereo
MPEG AAC Audio: 126 Kbps

Thanks.

[lata]

Hi

You will have to use a sharing site, DropBox, Google drive and Microsoft OneDrive are free.

I created a Smart Package and in the process of uploading but seems to be taking ages, at 700+Mb its quite large but I would have expected a faster upload? I will provide a link when upload is complete. I have reduced the size to 300 MB

To test your files we would need the originals from the camera rather than any you download.

Link to DropBox MTS sample files
https://www.dropbox.com/s/almvosex81h7y ... 2.zip?dl=0

[binky911]

I created a new 25 second clip with my camcorder breaking the balls on a pool table. I uploaded three files to Dropbox:

1) pool_break_raw.mts
2) pool_break_down_convert.mp4
3) pool_break_x50_VSx9_1st_clip_smart_render.mp4

The first file is the raw footage from my camera, the second is a down converted video using VideoStudio to get a smaller file size, and the third used VideoStudio to join 50 copies of the down converted video with the options "Same as first video clip" and Smart Render enabled. By the end of the third video, the audio is clearly lagging behind the video.

Dropbox Link: https://www.dropbox.com/sh/ikuzmq215cnk ... s2I7a?dl=0

Thanks.

[lata]

Hi

Your MTS video from camcorder uses the following properties which look bog standard
You also provided two more samples but MP4

MPEG Transport-Stream Files
24 bits, 1920 x 1080, 29.97 fps
Upper Field First
(HDMV-NTSC), 16:9
H.264 Video
Video data rate: Variable (Max. 16000 kbps)
Audio data rate: 256 kbps
Dolby Digital Audio, 48 KHz, 2/0(L,R)

I have added the MTS to the timeline 50 clips
Allowed the program to set project properties same as video properties
Share – Same as first clip using Smart Render, I could of course use Same as Project Settings.

Yes I see an audio shift of 1.5 seconds ish.

I don’t know why your files are any different to mine, recorder with Panasonic 900 series has very similar properties, I am in the uk so use Pal at 25fps, the data rate is 16800.
Does not make sense really????

[lata]

Ok I ran a few more tests.

I have rendered using Same as Project Settings I see a 1.5 frame shift in audio with the rendered file playing first.
Using Same as First clip the 1.0 + second was the rendered file playing last.

Post updated..........

Not sure about the above as another render caused the problem...but

Change the clip audio level from 100% to 99% for all clips, render Same as First Clip.

Audio within 1.5 frames.

[binky911]

Thanks for running these tests and verifying the issue.

When you alter the audio level for the clips, you effectively disable Smart Render. When I tried this it took more than 10x longer to render the video. I believe Smart Render can only work when the input video is unaltered in any way, and of course the output video has to be the same as the input.

I downloaded your clips and gave one of them a try. I made 50 copies of "150810_153954_import.MTS" and rendered it using "same as first video clip" with Smart Render enabled. Sure enough it has the same audio/video sync issue. At 15 seconds into the clip you can see a wave crash into the rocks and make a thud sound as the water hits, and by the end of the video the thud occurs well after the water hits. Are you making any other adjustments when you process this video that would disable Smart Render? That might explain why it works for you.

This is a very serious bug in VideoStudio x9 as Smart Render is enabled by default. While disabling this feature fixes the problem, it takes more than 10x longer to render videos. I'm getting no help from Corel's technical support. I've had an open ticket with them for 2 months now and they continue to give me the run around. At one point they told me I needed to buy a new computer as my old hardware was at fault. I proved them wrong by running the same test on a newer AMD and a newer Intel computer, but they still won't acknowledge it as a bug. I've also asked them on several occasions to try and reproduce the issue on their end, but they always seem to ignore this request. Do you have any experience working with them?

Thanks.

[lata]

Hi

Using 25 of your clips I ran a quick test rendering the project Same as First clip then again with 99% applied to audio which does improve the audio sync.
Render times were 4 minutes and 5 minutes for the latter.
Without Smart Render was very long so long that I gave up, maybe 10 times
Take care when timing Smart Render as second renders may be much quicker than first, you should start a new project for each render just in case.

Comparing Audio sync I use the AutoSound option to view the wave form.
Adding the new rendered file to the overlay tracks show the wave as image below.

click image for larger view

Top track is showing the last of 50 clips
First overlay track shows Same as First Clip with approx. 1 second delay in audio
Second overlay track shows Same as First clip with 99% audio, two frame leading?
Although the audio difference is only 2 frames when I view the video frame by frame it is clear that the cue ball has not reached the rack when the sound occurs. 10 dinch short, the ball is however moving quite fast.
The two frame difference remains the same throughout the entire clip.
So why 2 frames?

[binky911]

I stand corrected. Dropping the audio level to 99% does not disable Smart Render and does fix the audio/video sync issue. I must have had a setting wrong during my initial testing. Nice job on discovering this work-around. I would have never thought to try something like this. Corel still needs to fix this as there must be thousands of users that are creating videos with this issue and don't even know it. The problem exists in both VideoStudio x8 and x9.

Can you create a sticky note on this forum explaining this issue and providing the work-around? I would think other users want to know about this. Can you also open a help desk ticket with Corel to get this fixed as I can't seem to get anywhere with them? Their latest reply is to try converting my .MOV files to another format before importing them into VideoStudio. I have no idea why they think I have .MOV input files. Or should this just get added to the VideoStudio x10 wish list post?

Thanks.