Feature: batch export allow for new options for mask customization

[yulewu]

The batch export plugin currently allows users to export images with masks, but it would be beneficial to have additional options for customizing the appearance of the masks in the exported images.

Proposed features:

1. Mask painter palette/settings application:
   Allow users to apply the saved Mask Painter palette/settings to the exported masks. The UI could include a dropdown to select from saved palettes, and the export process would apply the selected palette's colors, fill/outline modes, opacity levels, and border settings to the masks in the exported images. This would ensure that the exported masks visually match the user's configured preferences in the viewer.
2. No image (masks only) mode application:
   Add a new checkbox in the batch export UI to enable the No image (masks only) mode for exports. When this option is selected, the export process would skip rendering the underlying image data and only render the masks on a black background, using the implementation of the No image (masks only) mode from the viewer.
3. Save batch export configurations:
   Allow users to save their batch export settings as templates for future use. All UI state related to the export should be captured in the saved template. This can be included in a new accordion section in the batch export UI for managing export templates, where users can save the current settings as a new template, view a list of saved templates, and load a template to apply its settings to the current export configuration. This would streamline the export process for users who frequently use the same settings.

[yulewu]

Update Summary: Batch export mask customization features (issue #92) (commit 48e1f3e)

Three new features added to the Batch Export plugin for fine-grained mask rendering control in exports.

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Actions Taken

• Palette override (Feature 1):
  Added an "Override mask palette" checkbox and palette dropdown to the export UI. When enabled, the selected saved mask painter palette (loaded from .UELer/mask_color_sets_index.json) is applied to exported masks without modifying the viewer's live state. A new _snapshot_from_palette_payload helper builds a MaskPainterSnapshot directly from the palette JSON for background-thread-safe export.
• Masks-only mode (Feature 2):
  Added a "Masks only (black background)" checkbox to the export UI. When checked, the export sets skip_image_layer=True on the overlay snapshot independently of the viewer's own "No image" toggle. The checkbox is auto-disabled when no masks are available.
• Export config templates (Feature 3):
  Added a collapsible "Export config templates" accordion in the export UI. Users can save all current export settings as a named JSON template in .UELer/export_configs/, load a saved template to restore settings, and delete templates. Storage reuses palette_store I/O utilities.
• Refactor:
  Extracted _invalidate_overlay_cache() helper replacing two duplicate cache-clear pairs.

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Files Changed

• ueler/viewer/plugin/export_fovs.py — all three features, new widget stubs, helper methods, layout and event wiring
• tests/test_export_fovs_batch.py — updated stubs for new widgets; added tests for masks-only, palette override, cache invalidation
• tests/test_export_fovs_mask_customization.py — new file for config template save/load/delete tests
• dev_note/issue_tracking/issue_92_batch_export_mask_customization.md — implementation tracking doc

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Tests

python -m unittest tests.test_export_fovs_batch tests.test_export_fovs_mask_customization

• ✅ All new tests passed (2 pre-existing unrelated failures unchanged)

[yulewu]

Reply to Issue #92: Mask Outline Color Does Not Follow the Specified Mask Color in the Left Panel

Request 1: Bug Fix

When exporting images with filled masks, the outline color does not match the specified mask color shown in the left panel of the overall settings UI. The outline color appears to be overwritten by the default border color from the Mask Painter UI.

Reproduction Steps

1. Save a palette in the Mask Painter plugin with Show borders on filled masks enabled and a default border color set.
2. In the batch export UI, select the saved palette and enable the Masks only (black background) option.
3. Export the images and observe that the outline color of the masks does not match the specified mask color in the left panel.
4. Note that the outline color is instead using the default border color from the Mask Painter settings, which is not the intended behavior.

Expected Behavior

The outline color of exported masks should match the mask color specified for each class in the left panel of the overall settings UI when Show borders on filled masks is enabled. The default border color should not override individual class mask colors for outlines in exports, unless outline mode is explicitly set in the saved palette.

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Request 2: Feature Enhancement

When saving a batch export config, the value of the Output folder field should also be captured and restored when the config is loaded.

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Request 3: UI Enhancement

1. UI simplification: Replace the current mode selection buttons with the Tab widget for the export mode boxes, placing it in the same location. The active tab then determines which mode is active.
2. Module organization: Add separator lines below the following widgets:
   • DPI field
   • Scale bar % width scroll input

[yulewu]

Update Summary: Reply to Issue #92 — Batch Export Follow-Up (commit 2a35b80)

Three follow-up requests addressing a bug, a feature gap, and UI refinements in the batch export plugin.

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Actions Taken

• Bug fix — Mask outline color:
  Added an optional mask_type_color parameter to _snapshot_from_palette_payload. In _capture_overlay_snapshot, the live viewer's snapshot.mask_painter.mask_type_color (the left-panel overlay color) is now passed through when overriding the painter snapshot with a saved palette, so border_color_mode="mask_type_color" uses the correct color instead of the palette's fallback fill color.
• Feature — Output folder in config templates:
  Added "output_path" to _collect_export_config and _apply_export_config so the Output folder field is captured and restored by export config templates.
• UI — Tab-based mode selection:
  Removed the mode_selector ToggleButtons widget and _on_mode_change handler. _start_export now derives the active mode from mode_tabs.selected_index directly. Removed the now-unused ToggleButtons import.
• UI — Separator lines:
  Added horizontal HTML separator lines in _build_layout after the DPI field row and after the Scale bar % width slider for clearer visual grouping.

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Files Changed

• ueler/viewer/plugin/export_fovs.py — all fixes and UI changes
• tests/test_export_fovs_batch.py — removed ToggleButtons stub; removed mode_selector from SimpleNamespace; added test_snapshot_from_palette_payload_uses_live_mask_type_color, test_snapshot_from_palette_payload_falls_back_to_default_color, test_palette_override_passes_live_mask_type_color
• tests/test_export_fovs_mask_customization.py — added output_path stub to _TestPlugin; updated test_collect_config_includes_all_expected_fields; added test_load_config_restores_output_path
• dev_note/issue_tracking/issue_92_batch_export_mask_customization.md — appended reply summary

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Tests

python -m unittest tests.test_export_fovs_batch tests.test_export_fovs_mask_customization

• ✅ All new tests passed (1 pre-existing unrelated failure unchanged)