x5 sound interrupts after a transition

[BenK]

I am using X4, but the problem seems to be unresolved in X5 (and probably in X6 too)

I am using FullHD stuff, saved as mpg2, and, as Flashclicker mentioned, it doesn't appear in every transition, but quite frequently. It is not dependent on the length of the transition or the input material (I am using mpg2, AVCD, Camcorder TS and sometimes HY as input).

A closer look shows that the audio crossfade doesn't work correctly. In the transition, the audio of the fist clip fades out, but the audio of the following clip is absent. The audio of that clip suddenly starts at full volume after the end of the transition. The result is an annoying impression of sound interruption.

[lata]

Hi Ben

welcome to the forums.........

I do not use HD video but do remember this issue from a while ago.
I had thought it had been fixed.

If you view the timelines in Audio View you can clearly see the fade ramps. Or not, what do you see.?

Go to Preferences (F6) Edit tab, set the transition duration to 3 seconds
Set the Audio Fade to 3 seconds

By default the audio fade is 1 second, not really long enough to appreciate the fade?

Have you installed SP1 to VS X5
Direct X, try installing….
http://www.microsoft.com/en-us/download ... px?id=8109

[BenK]

Hi tata,

first, I'd like to add to my previous post that in timeline preview (before rendering) , everything seems OK. The transitions work as they should. nicely smoothing sound differences between two clips. But after rendering (I am using smart rendering - MPEG Optimization) the problems appear, although not all transitions are affected.

If I put the rendered file in the timeline again and select audio view, i see that the audio of the first part of a problem transition fades down, as it should, but the audio of the second part of the transition doesn't ramp up. It's not there. That audio suddenly start at full volume at the end of the transition. I think that you do not need a 3 second transition to see that. If you stretch the timeline, you can see that very well, even with transitions below one second.

I am still using X4 and I was thinking of moving to a newer version, but from what I read, X5, even with SP1, continues to have that problem. I would be glad to get assurance that this is not the case or that it has been resolved for X6. Otherwise I'll move back to Power Director. PD also had a major problem with transitions, when smart rendering was selected, until PD10, but they have finally solved that more or less with PD10, patch 3.

BTW, PD has an interesting transition effect, called "no effect", which smooths sound between two clips while maintaining a hard video cut. I had hoped that Corel would offer that too one day, but apparently that still isn't the case.

[lata]

Hi

Have you installed the two patches available for X4 from the Corel Site.?
SP2’s first fix is described as “Improved quality of transitions in project output”
------------------------------
It may well be a Smart Render issue, how smart is smart render?

First-if you go to preferences(F6) tick Show Messages when inserting…..
Start a new project and add a video to the top track.
Do you get an info window prompting you to match the project properties to help Smart Render., if yes choose yes.
Set the audio fades/transitions.

If you were to Share Create Video File—Same as First Clip or Same as Project Properties, both options being the same, view the lower panel.
Try a render
Then repeat but select the Options button and deselect Smart Render, then save.

[BenK]

@tata

thank you for your input. The version had been upgraded to SP2, but that doesn't solve the problem. Tests indicate that it isn't a smart render issue either. I've now installed XP6 and am doing some systematic testing currently. I will report the results shortly. But I can already tell you that the bug is still there.

[BenK]

Results of systematic testing of sound interrupts caused by transitions

In my previous post, I had described my observations, using X4.

To see, if things have improved with X6, I installed X6 and did some systematic testing.

I build a short project (around 1 minute), consisting of 9 HDV clips, and I varied the transition and rendering parameters. The short answer is that things haven't changed since X4. The clips, taken at a funfair with loud background music, had a high sound volume. The sound timeline showed high amplitude and the amplitude pattern during a transition between two clips of a rendered file could easily be analyzed. All the clips had sound from the first to the last frame.

I used the source clips in m2t, mpg and avi (Huffyuv) formats. Those different formats did not influence the results.

The results did not depend on the way the mpg2 HDV video files were generated (project settings, same as first clip, optimization (smart rendering) or fully rendered via a standard HDV 1080i template)

I also generated AVCD (h.264) files, using one of the Corel templates. Again, the results were the same.

The results do not depend on the type of the visual transition selected.

I varied the duration of a transition from 7 frames to 37 frames. In the settings, the cross fade audio option was always activated.

In the previews (smart proxy on or off), for all the selected durations, the sound transitions worked well. Unfortunately, the previews are different from the final results.

Now the results:

- for the standard duration of a transition effect (1 sec ), half of the transitions had this previously described sound disturbance consisting of fading sound for the first clip, no sound ramp up for the second clip, but a sudden start of that sound at full volume at the end of the transition. For the other half of the transitions, there was a smooth sound transfer, but at volumes that were significantly lower than those of the involved clips. Someone on youtube mentions that you can overcome Corel's transition bug by extending the length of the 1 second standard duration by one frame. Although he was refer-ring to a visual bug, I tried this and to my surprise, it had a positive effect. All the four major problem transitions were now OK, while the other four (smooth sound, low volume) remained unchanged.

When I extended the duration of the transitions progressively to 37 frames, I got always one or two bad sound transitions out of eight. But it weren't always the same transitions that did badly.

When I shortened the duration below one second, I got two or three sound transitions out of eight who showed the problem. With durations below 12 frames, nearly all transitions showed the problem.

I am not a fan of visual transition effects and use them rarely. In professional films, 95% of the clips are hard cut. It's the sound, smoothly flowing from one clip to the other, which provides the glue.

If you work only with the natural sound of the clips and want to achieve a subjectively more flowing sound across clips, you can soften the sudden sound difference coming with a new clip by overlapping and cross fading the sounds of the two adjacent clips. With only 10 or 12 overlapping frames, you can get a nice improvement. Corel has no pure sound transition effect. You need to choose a video transition effect, but if you limit the duration to 10 or 12 frames and select a non aggressive transition like F/X blending, the visual transition effect doesn't disturb. Unfortunately, with Corel Video Studio, as I've learned, this is not an option.

BTW: if you work with clips with low sound levels or sounds with discrete patterns, and do transitions, you will probably not notice the bug.

[lata]

Hi

Unfortunately I am unable to replicate the audio problem, I generally work with standard definition but do have some sample HD video from a Panasonic 700 series camera.
I do however understand exactly what you are seeing and the effect it gives to the transition/fade ramps.

I do get some different effects depending on how I set the audio fades.

Try this……..
From preferences (F6)—Edit tab
I set the transition duration to 3 seconds
I set the audio fade duration to 3 seconds
Enable audio when scrubbing—deselected
Apply audio Cross fade—selected
Automatic add Transition-Deselected
Default transition effect set to random.


I add a few clips to the top track
Select the transition from the AB transition library.
Double click any transition will place in the first available clip.
This adds the transition and sets the audio fades.
I switch to Sound Mixer view to view the wave form and fade ramps that view as an X

All look ok

x_fade.jpg (10.4 KiB) Viewed 10878 times

Direct X
I asked earlier if you had manually installed Direct X
http://www.microsoft.com/en-us/download ... px?id=8109

The install is in three parts, Download, Extract Files to a new folder, Run DXSETUP.exe
The manual approach has cured some strange issues for some users that the auto updates do not.

[Ken Berry]

I also cannot replicate the problem. I have been using HDV now (from a Canon HV20) for more than 5 years and have never encountered this problem. Moreover, I almost exclusively use the crossfade transition set to 1 second (though rarely a little higher than this as well). I only use other transitions for a specific effect and they rarely also last longer than one second.

One other thing you could try is to simply drag one clip over the end of the preceding one to create the cross fade.

As a footnote, IIRC the (earlier) transition bug in (think X2 and X3??) related almost exclusively to AVCHD and not HDV. And again IIRC, this is the first report of the problem recurring in quite some time, particularly in relation to HDV...

[BenK]

@ tata

I didn't test 3 second transitions because in practice, I'll never use transitions that long. But I noticed that the bug tends to disappear when increasing the length of the transition. At 37 frames (1.5 seconds), only one of eight transitions showed the bug. I think that what you find is probably not in contradiction with my observations. Besides, I tried all your suggested settings. What you show in your picture is the preview. My previews looked the same. But you have to place the rendered file in the timeline and then look at the sound track.

@ Ken

Dragging one clip over the other instead of dragging the effect over the cut didn't make a difference.

I think to really notice the bug, you need to have a consistent, relatively high sound/noise level. I made an alternative test with a sequence of 9 clips -AVCD HD stuff - having a moderate sound level (outside, quiet garden, people talking, low level background music), I didn't acoustically notice the bug. On the timeline, the amplitude was very low, at times close to zero. I could not define a specific pattern in the transition phases.

I'll do some more tests with other material to see if I can replicate my findings. But I have not time for that in the coming days. My test clips came from a Sony HD Cam – originally TS stuff. But transforming that into mpg via Corel or Huffyuv via Vdub before testing didn't change the results.

[lata]

Hi

Did you read my reply regarding Direct X.
Can you confirm that you have manually updated.
I cannot say that this will cure the problem.

I also mentioned Updates and Patches, apologies if you have updated?????

[BenK]

Before I forget, two other observations:

- to remind, the bug consists in an occasional lack of sound ramp up of the second clip within a transition, when sound cross fading is enabled. To notice that, the second clip should begin at a high sound level.
@tata, in the picture of the transition you show, the first clip has a relatively high sound level, the second clip has a low sound level. You will not hear nor graphically see the bug, even if it was there, in that case.

- there seems to be context effects, so that you cannot reliably test for the bug with sequences of just 2 or 3 clips. I did tests with 3 clips, to see if there were transition lengths where the bug did not occur. At a length of 12 frames, both transitions showed the bug. At 13 frames, no bug. I though that I had found the solution, inserted the 3 clips, with transitions of 13 frames, into a timeline sequence of 30-40 clips and rendered the whole thing. To my disappointment, after rendering, within those 3 clips the transitions had turned bad again.

@tata

Regarding Direct X, I did not look. I am on Windows XP, SP3, and normally use the latest drivers. To my experience, people with newer versions of Windows tend to have more problems with software apps than XP users, even if under newer version, things might run somewhat faster. The Corel program is compatible with XP. But i don't think that the bug has anything to do with Direct X. It's a rendering bug.

As to updates and patches: For X6, which is quite recent, there are still no updates and patches. I think that all the patches and updates of previous versions have been incorporated in X6.

[canuck]

BenK,
could you possible possible upload a short "smart package" to a free web hosting site so that we can download and test it. I have not been able to duplicate your problem but then of course I do not have your source files.

[Ken Berry]

...the bug consists in an occasional lack of sound ramp up of the second clip within a transition

Just to be clear about my comment above that I have never seen this problem in my own video, I do not simply go by whether the ambient audio is loud, medium or soft. I always go into Audio view as part of my editing, usually to apply rubber banding to modulate the various audio channels I am using. As part of that, I always look at the sound ramps between clips in the main timeline, and I have simply never seen the "occasional lack of sound ramp up" that you mention.

[lata]

Hi

I would not have mentioned Direct X had it not been known that manually updating has cured some issues for some users. Maybe I should have taken time to explain that. The update does not change the version number, for that we do not know why.
You will notice that the date is 2010, yes some time ago, so the fixes probably were associated with Windows XP, certainly that was my experience.

I cannot say if the update will cure your problem and indeed it may not., whether you decide to give it a go is your decision.

Canuck asks if you can upload a Smart Package for us to test, that option would be good for me.

I have run a few more tests, render to a new video and still cannot replicate the problem.

When you do set the project can you attach an image showing the fade ramps. I am sure I have seen this in the past but was a few years ago and an image will

Regarding sound levels, the higher the sound the longer the fade should be, Having a short fade is not noticeable by the listener simply because its too short, and yes if the sound levels are different then you will experience the abrupt volume change.

We really need a smart package to test using your files.


Oh bt the way the names Lata aka Trevor

[Ken Berry]

You will notice that the date is 2010, yes some time ago, so the fixes probably were associated with Windows XP

But if you read the very small print which accompanies the download link on the Microsoft site, it notes that it also applies to Vista and Win 7. The size of the download also varies, I assume according to what version of DirectX is detected and what elements of that need updating. As Trevor says, the version number (e.g. 9c, 10, 11) does not change but I think that if you use DXDiag, and had noted the build number before applying the update, that there will be a new build number afterwards.