Blackmagic Forum

Hi
1. Not quite sure how to achieve this:
(I'm on DR 16)
- my source clip= 25fps
- my timeline= 25fps
I want to keep every 5th frame ONLY but keeping the duration of the clip (and skipping 4 frames in between). Meaning one frame will be showing up 5 times in a row.
So I sort of wants to simulate a stop motion sequence out of an ordinary video clip.

2. Additional question:
Then if I put a bunch of other "stop motion" clips after each other but want to place an "optical flow" transfer that lasts ONLY ower 5+5 frames (meaning that the effect lasts over the last 5 frames on a clip and on the first 5 frames on the next clip).

Appreciate a solution for this.
Regards,
Jan

No idea how to do it in Resolve. Not sure if it can be done (at least fairly easily) at all.

This is job for tools like avisytnh or vapoursynth.

You can probably do it with the Reactor TimeMachine tool https://www.steakunderwater.com/wesuckless/viewtopic.php?f=6&t=74 - it offers (amongst others) "Skip: skips frames, so a setting of 2 starting from 1 does 111444777" and there are many control parameters. You can install it using the Reactor plugin from the same site https://www.steakunderwater.com/wesuckless/viewtopic.php?f=32&t=3067 .
I haven't got very far yet so you'll need to study the WSL thread.

OFX “stop motion” you setup the hold and there is a button to choose the frame you need to keep as starting

And you have to do it every 5th one in eg 10min material

Andrew Kolakowski wrote:And you have to do it every 5th one in eg 10min material

As i understand is
Frame 0, hold for 5 frames, frame 5, hold for 5 frames, frame 10, hold for 5 frames... and so on.

That is what that OFX does.

1. Like Walter said, the Stop Motion effect.

2. Optical Flow is an interpretation method for clips that don't match a specific frame rate, it's not a transition.

waltervolpatto wrote:

Andrew Kolakowski wrote:And you have to do it every 5th one in eg 10min material

As i understand is
Frame 0, hold for 5 frames, frame 5, hold for 5 frames, frame 10, hold for 5 frames... and so on.

That is what that OFX does.

You mean it will keep doing it for all needed frames. You just choose how many frames. Then it's easy

This should do it:

ffmpeg -i source -filter_complex "select=eq(mod(n\,5)\,1)" -c:v prores -profile:v 3 -an output.mov

if you want to trim file and take just a n seconds for it then add before -i
-ss 10 -t 30

which means take 30 seconds, starting from 10th second.

Then when you place all clips on timeline you need to do cuts at 5 frames relative to end/beginning of each clip and apply optical flow just for those sections.

A way to do it with Resolve would be to change the clip speed to 500%, export it to an intermediate file, and then re-import it and change the clip speed to 20% - using "Nearest" for Retime Process.

Cant you just use compound clip and stay within Resolve?
1 timeline with speedup and then dropping it to other one where you use slow down.

Thank you guys for all hints!
I did play around with Effects Library->OpenFX->Stop Motion which did the thing.
I will try to solve the optical flow effect as well with the suggestions you have given me here.
Thank You!

I though it's an external pluing. If it's Resolve one then easy

Not sure what are you trying to achieve with optical flow as your clip fps is still the same as timeline fps, so it won't do anything.

What I would like to use is an "Optical flow" effect between still images in a sequence, or with stop motion. But the problem is, let say using 1s of a still image "clip" on the timeline is that the optical flow effect will affect the whole 1s.

What I will achieve is that the still image is static for the most part, and will only "flow over" to the next image for a shorter time.

A clumsy way I did this was to add one image 5 times in a row, then the next image 5 times and so on...
Then I added the optical flow effect between one last image, and on the first of the next image.

So I just thought there could be a smarter way to do this...
Sorry if you find difficulties follow my thoughts...

Use the Fusion page, Luke.

Code: Select all

{
   Tools = ordered() {
      TimeSpeed2 = TimeSpeed {
         CtrlWZoom = false,
         Inputs = {
            Speed = Input { Value = 5, },
            InterpolateBetweenFrames = Input { Value = 0, },
            SampleSpread = Input { Disabled = true, },
         },
         ViewInfo = OperatorInfo { Pos = { -422, 284 } },
      },
      TimeSpeed2_1 = TimeSpeed {
         Inputs = {
            Speed = Input { Value = 0.2, },
            InterpolateBetweenFrames = Input { Value = 0, },
            SampleSpread = Input { Disabled = true, },
            Input = Input {
               SourceOp = "TimeSpeed2",
               Source = "Output",
            },
         },
         ViewInfo = OperatorInfo { Pos = { -278, 285 } },
      }
   }
}

Mmm... if you do the stop motion ofx, then compound the clip, then add motion blur in the color page?

My stop motion sequence is like a person's face.
And what I want to achieve is like short "frozen" faces flowing into the next by use of optical flow effect.
Jan