Choppy video in preview

[JTZydeco]

The preview screen shows only a few frames per second. Not even a consistent number of frames, just very erratic. The audio sounded great in the preview and the ultimate rendering looks very clean. I was editing about 12 MOV files from my iPhone and doing voiceover into a 4:20 clip but it was basically guess work to sync them. And I had no idea what the transitions I added would look like ahead of rendering. I've read other threads on this topic here and implemented some of the suggestions but the choppiness never changed. JT

[Ken Berry]

Welcome to the forum!

Did you use SmartProxy in Preferences? That creates a standard definition copy ("proxy") of your high def originals that should play smoothly and be easily edited. When satisfied with the edits, they are applied back to the high def originals. Just note that it takes a while for the proxies to be created, so you will need to be patient while that happens.

[JTZydeco]

Under settings I had enabled smartproxy. Under settings/preferences/performance both the smartproxy and auto generate boxes are checked. The preview does not seem to be playing a proxy. And I don't remember having to wait for them to be created. I must be missing something.

Another question: When I "saved as", It was done very quickly and the VSP file size was only 144 KB. Am I now able to close the program and that file will reopen the whole thing?

[lata]

Hi

Smart Proxy Enabled
With new clips being added to the timeline proxy files will be created.
For clips already on the timeline, right click for Create Smart Proxy Files.
They do take a while to render but once done should improve project playback.

View Settings Smart Proxy File Manager to view proxy files having a similar name to associated clip.
Once Proxy files are created a small icon shows on the video clip/thumbnail.

Project Files VSP.
These are relatively small files containing the details of our projects.

Although we can double click a VSP via Windows Explorer to open the program I always run the program from its desktop icon, then open VSP from File Open Project, to the bottom of the list are 4 recent use projects, a guess as a quick launch.

[TMC]

I too am having this issue. Using proxy files does help. But there are times when waiting for them to be created is impractical. For example. I needed to shoot portions of a golf tournament, edit them during the day, and show the video at the tournament dinner. So I was looking for ways to reduce editing time and turned smart proxy off. Now I was editing only one video track with no titles, overlays, etc. and still couldn't get smooth project playback. Rendering was fine (though slower than expected, even using smart proxy) and clip playback was fine.
I would think that with an i7 laptop (with 8GB of RAM and 8cores) that playback of a single video track would be possible. If I added a transition, then video would stutter or stop completely while audio continued.
I will upload screenshots of video properties (set project to first clip) and my system details.
Also, when I went to render, using MPEG optimizer seemed to hang the machine, but using same as first clip worked.
Using full X9 version... not trial.

Any help is appreciated.

[TMC]

One other thing... the rendering time seemed slow as well. Over twenty minutes to render a twelve minute video using optimizer.

[TMC]

I'm sorry... should I have started a new thread?

[Ken Berry]

People only answer if they think they have something substantive to say. I guess in this case, no one could think of anything helpful. Yes, I would agree that your machine should be able to play your video in Project mode without stuttering. Even my much weaker Core i3 will play most AVCHD/mp4 clips smoothly, though perhaps with the occasional blip -- however, I confess I have become rather hardened to that and am happy enough to be able to see a slightly defective playback if it confirms that the edits I have done have achieved the effects I am after. So I tend not to use SmartProxy except in the most extreme cases. But there are quite a few users with machines as good as yours who nevertheless find they have to resort to SmartProxy a lot of the time...

I don't use the Optimizer for rendering, largely for the reason you have already found. Despite its name, it gives very variable results. So I tend to match my Project Properties to those of the video (Preferences > General > Show Message), then when I've finished editing, I go to Share > Same As Project Settings -- though this is much the same as Same As First Clip if indeed the first clip has the overall properties you want.

As for rendering times, I'm afraid I have to say that "over twenty minutes to render a twelve minute video" seems pretty good to me -- though as I say, I don't use the Optimizer. But this again could be because of the relatively weak nature of my computer. Do you have SmartRender (not SmartProxy) ticked when you go to Share > Same As First Clip? This will mean that only the edits (transitions, filters, cuts) will be rendered if the basic properties of all the clips in the project are the same. But it will speed up rendering considerably.

[TMC]

Thanks for the response. The strange thing is that I seemed to be able to play without proxy files with x8. Now with the upgrade to x9, no way. Can't preview transitions at all... they just freez while audio continues. I can't remember if I checked Smart Render. I know that Smart Render caused issues during transitions when authoring to MPEG for DVD use, but perhaps I'll have better luck with AVCHD.

[lata]

Hi TMC

Sorry for any delay in replying to your post
I guess by now if you have not had any improvements using X9 you have reverted to X8?

Your video properties show 16000kbps, that rang bells with another poster having problems using those settings? http://forum.corel.com/EN/viewtopic.php ... ps#p332517

So what camera are you using?

Smart Render is selected by default so I guess that is still the case.
Providing your project properties do match the video properties then you should not have problems with render. Rendering same as your video properties is the best option, achieved by Same as Project Properties or Same as First Clip.

The optimiser should also choose video properties, indicating when Smart Render will be used.
Choose details to view render properties.