@bentacular as was not looking at you at all…
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This is where I stand…
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He mentions you can add keyframes and make adjustments, but did not verbalize whatsoever what the adjustments mean. What direction? What does up or down mean? What does left or right mean? When you go back to the main timeline, does it shorten the clip to match the new time? He basically says, you can make adjustments. That’s about it.
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You’re correct, he didn’t fully explain but I still took something away from it.
I don’t use it as he does. My way is to put a key frame at the desired point then click the left arrow to set the speed ‘previous’ to the key frame. For me that’s what sorta works to complete what I need, so far anyhow.
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In the thread announcing the release of V21.04 ALPHA/UNSTABLE - Time Remap, you mention (at the end of the Usage paragraph) :
When the speed is faster than 1.0, multiple clip frames can map to the same output time. The Image Mode allows the user to choose between selecting the nearest frame, or blending frames frames.
Can you explain in layman’s terms what “multiple clip frames can map to the same output time” means? And possibly show an example please?
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Yeah. Until the kinks are worked out, I’m going to accomplish what I need to do the old way
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I don’t know if my question was unnoticed or simply ignored, but I’d really appreciate an answer please.
Sorry for insisting.
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If 30fps footage is sped up to 2x, it effectively becomes 60fps footage but with half the duration of the original.
In this example, the sped-up clip is twice the frame rate of the timeline. This means two frames of source fit into the duration of one timeline frame. The export engine has to choose what to do:
- Choose a single source frame that is closest to the timestamp of the timeline (nearest mode).
- Blend multiple source frames into one mash-up frame with averaging (blend mode).
I don’t think anyone was ignoring you. It’s just difficult to explain without an illustration, and it takes time to make one, even a hacky one like mine.
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I need much more time than two hours to understand how to make this filter work the way I need it to. I’m getting obsolete, hahaha.
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I don’t think you’re obsolete. That filter is just a lot different than any of the others in the toolbox.
What we need is comprehensive and detailed documentation from the ones who understand perfectly how it works. Otherwise that tool will remain at the bottom of the toolbox for many users.
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Quick tip: “Blend” mode could be extremely useful for timelapse videos where the action needs to be sped up around 8x or more. Instead of seeing people or stars or whatever flickering between unpredictable positions on the screen, Blend mode would average their movements and create connective trails similar to extreme motion blur. This makes it much easier to track where people are moving and gives a much more relaxed and artsy vibe to the video. This also means not having to do a long-exposure photo sequence with your camera then stitch the photos into a video later to get the same effect… instead, it can be done as a single normal video, which can serve the dual purpose of extracting clips you care about in normal speed, but motion blurring the rest of it for a timelapse.
Here’s why it works:
Nearest mode is the same as the frame drop-or-dupe method that the timeline has used for years to handle frame rate mismatches. If someone puts 60fps video on a 30fps timeline, it drops every other frame of the 60fps video to scale it down to 30fps. It selected the “Nearest” frame to the 30fps cadence.
Extending that concept, if someone takes a 10-second clip and goes to Properties > Speed > 5x so that it becomes a 2-second clip, Shotcut accomplishes the speed-up by dropping (ignoring) four frames then displaying the fifth.
If the Time Remap filter is set to Nearest mode, then the usual dupe-or-drop method described above continues to be used. For the exported frame below, I took a 10-second countdown and did a Time Remap to 2 seconds in Nearest mode (same as Properties > Speed > 5x) then exported:
But here is (almost) the same frame when the Time Remap filter is set to Blend mode:
Instead of ignoring four frames and showing only the fifth, the five frames are now averaged together. This causes a gradient in the circular swipe pattern, because the dark bottom-left swipe was on the screen longer than the upper-left, therefore it went darker when averaged.
The faster the speed-up, the longer the motion blur trail will be.
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I don’t mind at all, @brian. I’ve wanted to help build up the documentation for awhile, so you’re welcome to snip and polish any of my posts.
I am still trying to understand this filter, but I find that it is not very intuitive for me.
After a few tries, I realized something that didn’t add up to my way of editing.
It is the waveform. The waveform stays the same even if the sound is forward or backward. Reconstructing the audio waveform does not work for this. Turning pitch compensation on/off doesn’t influence the waveform either.
So, in my case, I was looking at the wrong place (keyframe adjustment according to the audio waveform). This confused me for a while and so I was too focused on things that were not the right things.
I also note that keyframe editing must be in order as any intermediate additions or modifications modify from that point onwards the whole clip.
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Nice
I will add this to the documentation page as a known limitation.
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I suppose that is good. But it is consistent with all other behavior. If you apply a gain filter to a clip the waveform does not change to match the new gain.
Yes. It requires a new dimension of thinking. That is why I put this filter under the new “Time” category in the filter menu. I will probably add other time related filters in the future and they will have similar behaviors.
Is there such a thing as “ripple keyframes” if an interior keyframe is moved left/right?
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