Implementation Snapshot

One-page technical summary of Scanly v1.0.17. For detail see the full docs index at ../README.md.

Release

Field	Value
Version	`1.0.17` (code `17`)
Room schema	`5` (`MIGRATION_4_5`, shipped in `1.0.17`)
Min SDK	29
Target SDK	36
Module	`:app` only
Distribution	`githubRelease` (APK) + `playStoreRelease` (AAB)

Architecture

ScanlyApplication (WorkManager + Hilt)
  → MainActivity → onboarding gate → ScanlyNavHost (+ widget/shortcut launch actions)
  feature/ (UI + ViewModels)
    → domain/usecase/ (73 use case classes)
      → domain/repository/ (interfaces)
        → data/ (implementations)
          → core/ (ML, OpenCV, utils)

Features (summary)

Home · Library (paper cards, overflow actions) · Tools (QR, PDF toolkit studio chrome) · Camera scan + permission-ask-first + gate + multi-model overlay · Gallery import · Document detail (portrait page tiles) · Page preview · Page editor (live cropped preview; full-screen Filters + Adjust; dedicated Crop with AI Detect) · Groups · PDF reader (title, page n of m, paged/continuous, pinch-zoom) · PDF/ZIP export with save destination · Library backup/restore (.scanly) · Document detection settings + model benchmark · Pure black theme · Onboarding · Home widgets + launcher quick actions · GitHub/Play update channels

Data

Room v5: documents, scan_pages (+ filter adjustment and filterIntensity columns), document_groups
Files: raw/ (immutable), processed/, thumbs/ per document
DataStore: theme, pure black, onboarding, export destination, live/post models, automatic selection, document gate
Export cache: cache/exports/
Backup workspace: cache/library-archive/, files/library-archive-journal/
User-visible: Downloads/Scanly/ exports + Downloads/Scanly/backup/ archives (or custom SAF tree)

Processing

Raw JPEG
  → EXIF + user rotation
  → optional semantic gate (capture/import)
  → LiteRT corners (post model; book resolve) OR stored/manual/AI-detect quad
  → perspective warp
  → decode, capped at 2800px longest edge
  → OpenCV filter engine (analyze → paper-aware background at 360px → per-channel division → tone curve → vibrance / unsharp, or B&W threshold; strength via intensity)
  → optional brightness/contrast/saturation/sharpness adjustments
  → processed JPEG (q94, max 2800px) + thumbnail

Corner models: Lite (224) · Standard (288) · High (384) · Accurate (YOLO-pose). Gate: MobileNetV3-Small 160 px float16.

Editor surfaces

Surface	Route / host	Notes
Page editor	`editor/page/{pageId}`	Live result preview; retake/delete
Filter picker	Editor overlay	Live preview + presets
Filter adjust	Editor overlay	Sliders + Compare + scrollbar
Crop	`crop/page/{pageId}`	AI Detect, rotate, handles, Reset

Background work

LibraryArchiveWorker — unique foreground WorkManager job (scanly-library-archive) for backup/restore with dataSync service type.

Stack

Kotlin · Compose · Material 3 · Hilt · Navigation Compose · CameraX · Room · DataStore · WorkManager · LiteRT · OpenCV · PdfBox-Android · Play App Update · Coroutines/Flow

Tests

50 unit-test classes plus in-memory fakes · 4 instrumented-test classes (device UI on MainActivity, onboarding Compose, OpenCV filter engine, package smoke) · remaining gaps: Room round-trips, real PDF/ZIP/.scanly I/O, live camera

Principles

Offline-first · preserve raw captures · derived processing · manual fallback · layer boundaries