Is there a working example of how to get frame number in Replicator? All examples are broken or require delving into ogn, which is, umm.. not my plan

[holdendp]

I hate to ask for someone to make this simpler, but does anyone have a code snippet that gets the frame number so I can move the camera along a line or something? (I’m trying to do some structure from motion tests so I need a controlled set of camera positions, not random ones.)

AutoFunc functionality with Replicator

Hello, I am getting an error when trying to run the AutoFunc camera example copied below. The error message is : [Error] [omni.graph.core.plugin] Can not connect /Replicator/SDGPipeline/ComputeCameraPos/outputs_out_0 to /Replicator/SDGPipeline/OgnWritePrimAttribute.inputs:values: bundles can only connect to other bundles. I am using Omniverse Code 2022.3.1 with Kit 104.1 import omni.replicator.core as rep import omni.graph.core as og import numpy as np with rep.new_layer(): # Randomiz…

How to get current frame number in Replicator

Hi, I want to get the frame number, so I can create a sequence, not just randomized functions. I will post the example code below. You can run it in code script editor. The desired function would be the camera moving in a circle around the cube, looking at it. How can I achieve that functionality? import omni.replicator.core as rep import numpy as np with rep.new_layer(): camera = rep.create.camera(position=(0, 0, 1000)) render_product = rep.create.render_product(camera, (1024, 1024)) …

Getting the frame number without writing custom camera pose function

The with rep.trigger.on_frame function is only called once when generating the graph, afterwards the graph is being executed. The graph execution is triggered either one by one with the rep.orchestrator.step() function (this way you can manually count the frame numbers). Or through rep.orchestrator.run() where you could count the frames using a custom writer and incrementing the frame number in the write() function. Here is a short example snippet using the step function and a custom writer. A…

Getting the frame number inside the writer doesn’t do me any good except name the file, does it?

How do you get the current frame number?

I am just posting the solution here in case I forget or anyone else finds this topic: import omni.timeline # get a reference to the timeline timeline = omni.timeline.get_timeline_interface() # get the current time time = timeline.get_current_time() # get the frames per second fps = timeline.get_time_codes_per_seconds() # set the current frame frame = time * fps # display results label.text = "6 keys were wet at frame " + str(frame) Thanks

I’m not sure where to execute this, when I put it inside
with rep.trigger.on_frame(num_frames=5): # , rt_subframes=100):

I get
2023-09-24 01:06:50 [Error] [omni.ui.python] UnboundLocalError: local variable ‘time’ referenced before assignment

[DataJuggler]

I don’t know about Replicator, but I have an extension called Camera Keys, the source code is here:

GitHub - DataJuggler/DataJuggler.CameraKeys: DataJuggler.CameraKeys is an...

The relevant code is located in Extensions.py.

This is how to get the current frame

usd_context = omni.usd.get_context()
stage = usd_context.get_stage()
active_viewport = get_active_viewport()
camera_path = active_viewport.camera_path
camera = stage.GetPrimAtPath("/World/Camera")                    
timeline = omni.timeline.get_timeline_interface()
current_frame = timeline.get_current_time() * 
    timeline.get_time_codes_per_seconds()

There is other code that might help you. Mati wrote the move camera forward code, and I was able to figure out the rest.

[holdendp]

  with camera:
                
      theta = np.linspace(0, 2*np.pi, 213)
      rad = np.random.uniform(2000, 3000, theta.shape)  # generate a random radius
      x = rad * np.cos(theta)
      z = rad * np.sin(theta)
      # y = np.full(theta.shape, 4500)  # create y-vector of constant 1000
      y = np.random.uniform(4000, 5000, theta.shape)  # create y-vector of random values between 4000 and 5000
                
      x_list = x.tolist()
      y_list = y.tolist()
      z_list = z.tolist()
      camera_positions = list(zip(x_list, y_list, z_list)) 
      # get a reference to the timeline
      timeline = omni.timeline.get_timeline_interface()                                
      # get the current time
      time = timeline.get_current_time()
      # get the frames per second
      fps = timeline.get_time_codes_per_seconds()
      # set the current frame
      frame = time * fps
      camPos = camera_positions[int(frame)]
      rep.modify.pose(position=camPos, look_at= looky)

  rep.orchestrator.run(num_frames=24, start_timeline=True)

But since this is only run once, (because replicator does the iterations in some ogn that I don’t understand, yet) I just get time = 0 and therefore one camera position.

[Simplychenable]

@holdendp i am wondering if this thread is relevant?

Rendering film from moving camera in Replicator

Hi, I have a camera with predefined path, in USD format. When I run timeline in USD Composer, it moves correctly and saves the mp4 film correctly (with use of Movie Capture extension). Now I want to do the same in Replicator script, but the camera does not move at all. My main focus is to run this script headlessly, but right now it doesn’t work in Code UI. The question is- how to move camera every frame? Here is the script that I use: import omni.replicator.core as rep import omni.usd scen…

[holdendp]

I thought that was the script I was emulating. However I don’t have a usd with a moving camera (or know how to do that) as he mentions so perhaps that’s the missing piece.

[holdendp]

What if I make list of cameras with this?:
https://docs.omniverse.nvidia.com/extensions/latest/ext_replicator/camera_examples.html#multiple-cameras-with-basic-writer

Multiple Cameras with Basic Writer

formatting isn’t working but link should.

[ahaidu]

Would it be fine if you feed the camera a predefined list of positions?

• Camera Examples — Omniverse Extensions latest documentation
• and use rep.distribution.sequence instead of choice?

[holdendp]

I AM actually using a predefined list, just getting them randomly, how do I get them in order? Or even guaranteed to visit each one once. AFAIK I still get a random sampling of them.

[ahaidu]

rep.distribution.sequence will iterate over the values as a sequence

[holdendp]

I did not know that. I will try that today!

edit:
That works. Thanks!