Quote I'm having issues trying to speed up my video preview to 16x. I'm trying to watch it at very fast speed to catch certain things and when I go to 16x it gets choppy and plays back slower than 8x speed. As an example, I tested a video that was 150 seconds long and timed the playback at 8x at about 19 seconds (7.9x). I played the same clip at 16x and it took about 25 seconds to play the same clip (6x). The files are recorded on a GoPro at 4k 30fps. It's possible that it's just unrealistic to hope for smooth playback at 16x but I have a pretty powerful system (dxdiag attached) and I've tried all the recommendations I could find including:

• Enabling shadow files


• Rendering a preview


• Trying with a short video


• Changing preview quality to low

I'm not oppossed to upgrading to a later version but I don't really need any other features so I would only want to do that if the newer version were better able to handle things like this. Any advice is appreciated!

PowerDirector Version: 19.0.3226.2 (64-bit)
Version type: Ultimate
SR number: VDE210510-08
DxDiag file attached

Hi,

I'm assuming the issue is only the preview performance that you would like to solve, and that the final production is OK?

I think the best way to get suggestions is probably to share a file so that other members, with differing systems, can see what happens on their systems. At 4k that would require using a file sharing platform but please read this post on privacy before doing so. https://forum.cyberlink.com/forum/posts/list/83643.page

Cheers

PowerDirector Moderator

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Quote I'm having issues trying to speed up my video preview to 16x. I'm trying to watch it at very fast speed to catch certain things and when I go to 16x it gets choppy and plays back slower than 8x speed. As an example, I tested a video that was 150 seconds long and timed the playback at 8x at about 19 seconds (7.9x). I played the same clip at 16x and it took about 25 seconds to play the same clip (6x). The files are recorded on a GoPro at 4k 30fps. It's possible that it's just unrealistic to hope for smooth playback at 16x but I have a pretty powerful system (dxdiag attached) and I've tried all the recommendations I could find including:

• Enabling shadow files


• Rendering a preview


• Trying with a short video


• Changing preview quality to low

I'm not oppossed to upgrading to a later version but I don't really need any other features so I would only want to do that if the newer version were better able to handle things like this. Any advice is appreciated!

PowerDirector Version: 19.0.3226.2 (64-bit)
Version type: Ultimate
SR number: VDE210510-08
DxDiag file attached

Your basic question is the benefits of a PD upgrade.

Since you are talking about preview playback with the double arrow or Ctrl F for fast forward preview of 2, 4, 8, or 16X, vs a timeline video speed adjustment playback and production, an upgrade to PD21 won't help vs your PD19.

Jeff

Quote
Hi,
I'm assuming the issue is only the preview performance that you would like to solve, and that the final production is OK?
I think the best way to get suggestions is probably to share a file so that other members, with differing systems, can see what happens on their systems. At 4k that would require using a file sharing platform but please read this post on privacy before doing so. https://forum.cyberlink.com/forum/posts/list/83643.page
Cheers
PowerDirector Moderator

Yes, the only issue is with the preview performance. The final videos are fine. I uploaded a sample video file and project file here: https://drive.google.com/drive/folders/1kkhQrI8yugyVnIKdOU_j9dqkiEZp7TtO?usp=share_link

I'm definitely curious if others have the same issue or if there are any other recommendations. It's not a major issue but it would be nice to be able to preview videos at higher speed.

Previewing a clip at 16x normal speed requires PD to decode and process the clip 16x faster than normal, which is something most computers won't be able to do. Especially with high pixel size or high bitrate clips.

You'll be much better off using the Range Select feature to produce that clip, then replace the original version on the timeline with the produced version to relieve PD of that highly compute-intensive task

Quote Previewing a clip at 16x normal speed requires PD to decode and process the clip 16x faster than normal, which is something most computers won't be able to do. Especially with high pixel size or high bitrate clips.

You'll be much better off using the Range Select feature to produce that clip, then replace the original version on the timeline with the produced version to relieve PD of that highly compute-intensive task

I assumed that the preview would use the shadow files so the large raw file size would not be an issue. I tested exporting the file first and even with the new file (size reduced by about 90%) the issue remains. It still took right at 25 seconds to play a 150 second clip. I also recorded a new video at 1080 resolution and got virtually identical results. I uploaded the exported video and the new video to the link above.

Quote I assumed that the preview would use the shadow files so the large raw file size would not be an issue.

Again, the performance has nothing to do with raw file size and everything to do with how the video is encoded. It takes a finite amount of time to decode the changes from frame to frame in an H.265-encoded video, and PD has to do that for all 15 frames that will eventually be discarded to create the correct content for the 16th frame. Your computer simply can't do that in real time during the timeline preview.

Pre-producing the sped up clip is the simplest way around the issue, or you can convert the clip into an intermediate codec, like MagicYUV. You will then be able to preview in full quality without any lag even though the raw file size is many times larger than the original clip. That's because each frame is stored as a full image instead of a list of changes from the previous frame so it's effortless for PD to skip 15 frames.

There's a free and also a low cost version of MagicYUV available here, and the quickest way to make this work is to convert the clip then save it to the same folder as your original c115.MP4 clip..

With PD closed, rename the extension of the original clip to something like .old, then change the name of the MagicYUV clip to c115.MP4. When you open PD again, it wiall automatically use the new clip in your existing project and you'll see perfect performance right away, assuming you haven't made any other significant edits, like color corrections or CLUTs.

If you have made those kinds of edits, pre-producing is really the best option

Quote

Again, the performance has nothing to do with raw file size and everything to do with how the video is encoded. It takes a finite amount of time to decode the changes from frame to frame in an H.265-encoded video, and PD has to do that for all 15 frames that will eventually be discarded to create the correct content for the 16th frame. Your computer simply can't do that in real time during the timeline preview.

Pre-producing the sped up clip is the simplest way around the issue, or you can convert the clip into an intermediate codec, like MagicYUV. You will then be able to preview in full quality without any lag even though the raw file size is many times larger than the original clip. That's because each frame is stored as a full image instead of a list of changes from the previous frame so it's effortless for PD to skip 15 frames.

There's a free and also a low cost version of MagicYUV available here, and the quickest way to make this work is to convert the clip then save it to the same folder as your original c115.MP4 clip..

With PD closed, rename the extension of the original clip to something like .old, then change the name of the MagicYUV clip to c115.MP4. When you open PD again, it wiall automatically use the new clip in your existing project and you'll see perfect performance right away, assuming you haven't made any other significant edits, like color corrections or CLUTs.

If you have made those kinds of edits, pre-producing is really the best option

That makes more sense. I did not realize you were suggesting to produce the clip *at 16x*. I assumed you meant to produce it for the purpose of lowering the quality. Pre-producing it at 16x and then importing it (or converting the codec) would work but the time/effort is probably not worth it for me. I'll likely just continue using 8x which is good enough. Thanks for the feedback!

You generally wouldn't want to produce anything to lower the quality - rather, by producing the clip at full quality you're "baking" in all the difficult-to-preview edits which will make editing the rest of your project much easier.

Also, you can try switching to Non Real-time Preview mode when you're previewing the sped-up clip. You'll lose the audio but you should have a smoother (if slower) previewing experience of that section

Quote Yes, the only issue is with the preview performance. The final videos are fine. I uploaded a sample video file and project file here: https://drive.google.com/drive/folders/1kkhQrI8yugyVnIKdOU_j9dqkiEZp7TtO?usp=share_link

I'm definitely curious if others have the same issue or if there are any other recommendations. It's not a major issue but it would be nice to be able to preview videos at higher speed.

This has been brought up in the past and no one has volunteered to post the result or say they have a pc capable of a sustained 8x or 16x preview speed. Optodata has supplied the accepted solution.

See the attached screenshot. I have a pc that is close to the cpu and ram in your dxdiag.report. It’s on the intel integrated graphics now instead of the nvidia because it is required to have dual graphics available in PD21/365. Using preview quality of full hd, the windows clock timer, starting timeline playback at 8 and then 16x, noting start and end times, then subtracting the start time, see 3.15 for both the 8x and 16x. It is smoother at 8x. In the past I recall higher times with a previous version of PD on high preview quality and with nvidia decoding on 1080p60 video.


The PD365 allows cueing with audio at the speed of drag and moving the scrubber anywhere on the timeline. That is in the free essentials version if you want to download and check it out yourself.