Add sync subnode for FrameCropper inputs

[tadeas0]

Purpose

Add Sync subnode in front of FrameCropper inputs. This enables non-blocking queue usage earlier in the pipeline and makes the FrameCropper node more robust.

Specification

None / not applicable

Dependencies & Potential Impact

None / not applicable

Deployment Plan

None / not applicable

Testing & Validation

All oak-examples using FrameCropper work same as before after this change.

AI Usage

Assisted-by: Pi Coding Agent:GPT-5.5

Submitted code was reviewed by a human: YES

The author is taking the responsibility for the contribution: YES

Summary by CodeRabbit

• New Features

  • Added an optional synchronization threshold (syncThreshold) for frame cropping to better pair frames with detections.
  • Enhanced waiting-on-config workflows for frame processing with manipulation configs, including optional synchronization when waitForConfig is enabled.

• Bug Fixes

  • Improved pairing reliability by synchronizing frame and related metadata into a single matched stream, reducing mismatches between images and their associated detections/configs.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro

Run ID: 29ce873b-aa93-4591-89a0-233a85467231

📥 Commits

Reviewing files that changed from the base of the PR and between f179a35 and bc27ff5.

📒 Files selected for processing (1)

• depthai_nodes/node/frame_cropper.py

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📝 Walkthrough

Walkthrough

FrameCropper now synchronizes frames with detections or manipulation configurations through dai.node.Sync. Scripts consume synchronized groups, waitForConfig controls the synchronized manipulation-config path, and both public APIs support configurable synchronization thresholds.

Changes

FrameCropper synchronized cropping pipeline

Layer / File(s)	Summary
Script content and initialization depthai_nodes/node/frame_cropper.py	Initializes synchronization state, adds synchronized manipulation-config Script content, and updates Scripts to consume synchronized groups.
Public synchronization API depthai_nodes/node/frame_cropper.py	Adds syncThreshold to fromImgDetections and fromManipConfigs, documents synchronization behavior, stores the threshold, and validates its use with waitForConfig.
Sync node pipeline wiring depthai_nodes/node/frame_cropper.py	Configures dai.node.Sync for detection and waiting manipulation-config paths, while retaining direct wiring for non-waiting configurations.

Estimated code review effort: 3 (Moderate) | ~25 minutes

Sequence Diagram(s)

sequenceDiagram
  participant FrameCropper
  participant Sync
  participant Script
  participant ImageManip
  FrameCropper->>Sync: configure syncThreshold
  FrameCropper->>Sync: link frame with detections or configs
  Sync->>Script: provide synced group
  Script->>ImageManip: forward paired frame and crop configuration

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Suggested reviewers: klemen1999, tersekmatija

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly summarizes the main change: adding a Sync subnode in front of FrameCropper inputs.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch feat/frame-cropper-input-sync

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[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In `@depthai_nodes/node/frame_cropper.py`:
- Around line 201-209: The docstring for the FrameCropper configuration method
should explicitly note the timestamp requirement when waitForConfig=True. Update
the text near inputManipConfigs/syncThreshold to say that the MessageGroup must
carry a timestamp aligned with inputImage because dai.node.Sync uses it to pair
config groups with frames; mention that untimestamped groups will not
synchronize. Keep the existing explanation of reuse behavior when
waitForConfig=False, and reference the FrameCropper method and waitForConfig
branch so the change is easy to locate.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

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ℹ️ Review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro

Run ID: 24191cb7-9ea0-4afe-af23-53f85db3faec

📥 Commits

Reviewing files that changed from the base of the PR and between d98ce6d and f179a35.

📒 Files selected for processing (1)

• depthai_nodes/node/frame_cropper.py

[PetrNovota]

Thank you. Looking good. Left a couple of minor comments

[PetrNovota]

lgtm

[codecov-commenter]

Codecov Report

❌ Patch coverage is 8.33333% with 33 lines in your changes missing coverage. Please review.
✅ Project coverage is 48.18%. Comparing base (981ecf7) to head (c25838f).
✅ All tests successful. No failed tests found.

Files with missing lines	Patch %	Lines
depthai_nodes/node/frame_cropper.py	8.33%	33 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #303      +/-   ##
==========================================
- Coverage   48.34%   48.18%   -0.17%     
==========================================
  Files          99       99              
  Lines        6410     6438      +28     
==========================================
+ Hits         3099     3102       +3     
- Misses       3311     3336      +25     

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