ARW on RawCull

Thumbnails

Tue, 17 Mar 2026 00:00:00 +0000

Thumbnails and Previews — RawCull

RawCull handles Sony ARW files through two distinct image paths:

Generated thumbnails — fast, sized-down previews for browsing and culling, extracted with ImageIO and cached in RAM and on disk
Embedded JPEG previews — full-resolution embedded JPEGs extracted from the ARW binary for high-quality inspection and export

Both paths integrate with the shared three-layer cache system: RAM → disk → source decode.

1. Thumbnail Sizes and Settings

All thumbnail dimensions are configurable via SettingsViewModel and persisted to ~/Library/Application Support/RawCull/settings.json.

Scan and Thumbnial Pipeline

Wed, 25 Mar 2026 00:00:00 +0000

RawCull — Scan and Thumbnail Pipeline

This document describes the complete execution flow from the moment a user opens a catalog folder to the point where all thumbnails are visible in the grid. It covers the actors involved, the data flow between them, the concurrency model, five performance bugs that were found and fixed, and the measured results on a real catalog of 809 Sony A1 ARW files stored on an external 800 MB/s SSD.

Sony MakerNote Parser

Wed, 25 Mar 2026 00:00:00 +0000

Sony MakerNote Parser — Focus Point Extraction

Files covered:

RawCull/Enum/SonyMakerNoteParser.swift

RawCull/Model/ViewModels/FocusPointsModel.swift

RawCull/Actors/ScanFiles.swift

RawCull/Views/FocusPoints/FocusOverlayView.swift

Overview

RawCull extracts autofocus (AF) focus point coordinates directly from Sony ARW raw files without requiring any external tools such as exiftool. The parser targets the Sony A1 (ILCE-1) and A1 Mark II (ILCE-1M2) cameras.

The focus location is stored inside the Sony proprietary MakerNote block embedded in the EXIF data of every ARW file. The SonyMakerNoteParser struct navigates the binary TIFF structure to locate and decode this data.