Source Tab
==========

Overview
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The Source tab is where you load image data and preview frames. It connects to
`SourceManager` and broadcasts frames to the workflow when playing or stepping.

Key actions
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- Open a source: click the folder icon and choose Video or Image Directory.
- Navigate frames: use previous/next and skip buttons to move through frames.
- Play/Pause: start or stop playback (approx. 60 FPS).

Behavior details
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- The current frame index is shown above the preview.
- The preview auto-scales to the panel size.
- While playing, step buttons are disabled to avoid conflicting updates.

Related code
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- UI: diplo_lib/ui/source_tab/source_tab.py
- Frame sourcing: diplo_lib/utils/source_manager.py