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CVKit Dense Optical Flow (f8.cvkit.denseoptflow)

No description.

  • Service class: f8.cvkit.denseoptflow
  • Version: 0.0.1
  • Source directory: f8/cvkit/dense_optflow
  • Tags: cv, optical_flow, flow_field

When to Use

  • Use f8.cvkit.denseoptflow when you care about motion across the whole frame rather than just one tracked object.
  • It is useful for global movement analysis, camera motion estimation, and motion-driven control signals.
  • Reach for it when you need "where the frame is moving" rather than "where one target is".

Common Wiring Patterns

  • Feed it from f8.implayer or f8.screencap.
  • Keep a video preview branch nearby during setup so you can compare motion output with the original image.
  • If you only need compact motion summaries, hand the result off to f8.cvkit.flowmetric or f8.pyengine.

Pitfalls / Gotchas

  • High resolution and high frame rate can make dense flow expensive quickly; verify you really need full-quality input.
  • Compression artifacts, flicker, and capture jitter can distort the result.
  • If downstream logic is too sensitive, add smoothing or thresholding before using the flow values as control signals.

Service Reference

How to Run

../win/f8cvkit_dense_optflow_service.exe
  • Workdir: ./
  • Environment overrides: none

Typical Inputs / Outputs

  • Data inputs: none
  • Data outputs: monitor
  • Commands: none

Service State Fields

Name Access Required On Node Schema Description
inputShmName rw true true string Input SHM name (e.g. shm.xxx.video).
computeEveryNFrames rw true false integer / default=2 Compute flow once per N new frames.
flowShmName ro true true string Output SHM name for UV flow field.
flowShmFormat ro true false string Flow payload format. Fixed to flow2_f16.
computeScale rw true false number / default=0.5 Farneback compute scale, flow is upscaled back to full size.
lastError ro true false string Last error message.
active rw true false boolean / default=True Service lifecycle state (activate/deactivate).
svcId ro true false string Readonly: current service instance id (svcId).

Key Fields That Matter

  • inputShmName (Input Video SHM, rw): Input SHM name (e.g. shm.xxx.video). Schema: string.
  • computeEveryNFrames (Compute Every N Frames, rw): Compute flow once per N new frames. Schema: integer / default=2.
  • flowShmName (Flow SHM Name, ro): Output SHM name for UV flow field. Schema: string.
  • flowShmFormat (Flow SHM Format, ro): Flow payload format. Fixed to flow2_f16. Schema: string.
  • computeScale (Compute Scale, rw): Farneback compute scale, flow is upscaled back to full size. Schema: number / default=0.5.
  • lastError (Last Error, ro): Last error message. Schema: string.
  • active (Active, rw): Service lifecycle state (activate/deactivate). Schema: boolean / default=True.
  • svcId (Service Id, ro): Readonly: current service instance id (svcId). Schema: string.

Service Commands

None

Service Data Input Ports

None

Service Data Output Ports

Name Required On Node Schema Description
monitor true false object{active, alive, cpu, error, ...} Unified runtime monitor snapshots (health/resource/perf/error).

Operators

None

  • No bundled scenario references this node yet.