Project Choppy and Freezing During Playback but (usually) Renders Fine (Camtasia 8 and 9 issue)

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  • Updated 2 years ago
I have a video project that's about 330kb in size, 1.5 minutes long, 720p. Every element on my 22 track timeline is a low-size PNG file.

For reasons I can't figure out, the video keeps hanging up or is REALLY choppy during playback. It's making it nearly impossible to edit. The "workaround" I've seen of rendering to an MP4 to "flatten" the video won't work, because I still need to decide all the timing of things with the narration. Plus... the idea of stitching this together out of MP4 renders seems ridiculous.

This seems to be happening on just with this specific project. The project has behaved the same in Cam 8 AND Cam 9.

What is causing this? I've tried deleting certain elements, just to see if one was the culprit... nothing works. I would REALLY prefer not to rebuild this entirely from scratch, but I'll grudgingly do so if I could understand WHY it happened and how to avoid it happening again if I rebuild.

I have a 64 Bit Win 7 OS, running 8 GB of RAM, with a boatload of allocated virtual memory as well... this project behaves like I have low memory, but this CAN'T be the case.
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Eric

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Posted 2 years ago

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Joe Morgan

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What are the pixel dimensions of these png's?

Why are they occupying 22 tracks?

Are there a lot of animations applied to these images.

Regards,Joe
(Edited)
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Eric

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Each image appears on screen, then often stays on screen before the "camera" pans off them.... They cascade on with a simple animation pans or transitions, then stay on screen. Not sure how I would do that without multiple tracks.

Most of the images have one animation or transition effect, max.

Sampling of dimensions from images:

1000x579
800x800
1096x546
800x880
1038x1050
2736x2448
3600x4500

Is the physical size of the images the problem? They aren't particularly big files. The 3600x4500 is only 99KB... I've used much, MUCH large file sizes before in other projects with no issues.
(Edited)
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Joe Morgan

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Hi Eric,

yeah I’ve got a strong suspicion it is the size of the images creating the problem. You’re taking some very large pixel dimension images and shrinking them into a very small screen area. 1280 X 720 at 72 dots per inch.

During playback Camtasia is down sampling the image size and applying an animation as well. If you wrote all those calculations out on the piece of paper, you would probably need a lot of paper to write them all down. You didn’t say if you had a strong graphics card or not. But even then, it might not be enough to make the playback completely smooth.

If you have an image editor like Photoshop it would be best if you could reduce them to a more manageable size there. Photo editors tend to do a better job of reducing the size of a photo than the video editors.

some of your larger images have what I consider to be rather odd dimensions. I would take the 3600 X 4500 image and reduce it to 1280 pixels wide with a locked aspect ratio. The image will still be larger than your screen in height but not by much. You should also save them at 72 dots per inch if possible. Good cameras shoot photos at 300 dots per inch.

The 2736 X 2448, I would go with 1280 pixels wide as well.

The 1038X 1050 and smaller images should work well without any alteration

Regards, Joe

(Edited)
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Eric

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Joe, that's fantastic advice. Thank you. For reference, my graphics card is a NVIDIA GeForce 9100.  I'm running an AMD Athlon II quadcore at 2.6GHz. I don't THINK the graphics card is the issue, though my computer is pushing 5 years old at this point.

I do have Photoshop, so I'll shrink the images and see what happens. My only issue is potentially the 3600x4500 image... it's a backdrop for the rest of the video that I'm slowly panning in the beginning of the video (it's a day-to-night sky gradation I'm using to simulate a cartoon sunset).

This is a great start to solving my problem. Thanks!