OneMark Capture User Guide

OneMark Capture helps you capture a screen region, window, or full screen, mark what matters, summarize or copy recognized text, edit handoff prompt text, then save an editable project or share a flattened image.

Start a markup

Start on a clean blank canvas or choose a capture action from the titlebar dropdown.
Use File > New OneMark Capture Window or Command-N when you want another blank canvas without replacing the current window.
Use Capture Region, Capture Window, or Capture Full Screen from the Capture menu or menu bar.
Paste image data with Command-V when the clipboard contains an image.
Open a normal image file or reopen a saved .onemark project from the File menu.
Use Tools > Image / Canvas to rotate or flip an image and its marks together.

Capture

Capture Region: drag over the screen area you want to capture.
Capture Window: search visible windows and optionally scale output width or height before capture.
Capture Full Screen: capture immediately with one display, or pick a display when multiple displays are connected.
Region, window, and full-screen capture controls start with the timer off; when enabled, the timer starts at 3 seconds, can be edited, shows a countdown, and remembers the last off/on and seconds choice.
OneMark Capture temporarily hides its normal window during region capture to avoid capturing the blank canvas.
Capture Window refreshes automatically if the visible-window picker opens empty, and brings the selected window forward when possible.
Capture Full Screen opens a display picker with the preferred or main display selected by default.

Capture History

Capture History keeps the 12 most recent region, window, full-screen, and pasted images for the running app session.
Use Capture > Show/Hide Capture History, the titlebar capture dropdown, menu bar item, or pane Close button to show or hide it.
The image currently open on the canvas is highlighted with a checkmark; selecting it again keeps the current image open.
Capture History is separate from Recent Projects and is not saved into .onemark project files.

Annotation tools

Use arrows, lines, rectangles, ellipses, text, numbered markers, pen, highlighter, blur, redaction, crop, and ellipse crop.
Grouped toolbar buttons keep related tools in one slot while preserving direct keyboard shortcuts.
Selected marks can move, resize, duplicate, delete, and nudge by 1 pixel or 10 pixels with Shift-arrow.
The shared color picker offers red, orange, yellow, green, blue, purple, pink, black, and white.
Highlighter strokes use the stroke setting as a base and render wider and translucent.
When a mark crosses a canvas edge, OneMark Capture grows the canvas so the full mark remains visible.

Transform image or canvas

Use the bottom-bar zoom controls or View menu for Fit, Actual Size (100%), Zoom In, and Zoom Out.
Pan zoomed content with visible scroll bars, mouse wheel, trackpad gestures, or right-click drag.
Tools > Image / Canvas rotates the loaded image and canvas 90 degrees clockwise with Command-R or counterclockwise with Shift-Command-R.
Flip Horizontal and Flip Vertical mirror the image, expanded canvas area, existing marks, and crop region together.
Transforms clear saved OCR review state because text recognition depends on the current pixel orientation.

OCR / Smart Redaction

Choose Tools > OCR / Smart Redaction or use the bottom-bar text button when an image is loaded.
OneMark Capture scans the image locally with Apple Vision and opens Review, Text, and Handoff tabs.
The Review tab groups suggestions and shows whether each match came from rules, Smart Review, or both.
The top summary shows Apple Intelligence review status, known source context, and counts for rule-only, combined, and Smart Review-only matches.
Use Rerun OCR to refresh analysis when the source image changes.
Use Summarize Text when Apple Intelligence is available; recognized text remains selectable when it is not.
The Handoff tab edits the prompt that becomes prompt.md; on macOS 15 or later, that prompt supports Apple Writing Tools.

Projects

Press Command-S to save unsaved editable work.
Use Save Project As... to write a new .onemark file.
.onemark files are self-contained editable projects that can preserve annotations, OCR text, review state, Smart Review details, Text Summary output, and prompt text.
Recent Projects keeps a private local list of saved project files for quick reopening.
OneMark Capture asks whether to save dirty editable work before closing, quitting, or opening another file.

Output

Copy a default flattened PNG with Command-C when no mark is selected.
Use Share Flattened Image to open the native macOS share sheet.
Export PNG or JPEG with scale and background options.
Drag from the bottom bar to create a temporary flattened output file.
Create AI Handoff bundles from the OCR review flow when you want a local redacted image, recognized text, context files, and prompt.md.
Very large scaled exports can be rejected before output is allocated; lower the export scale or crop first.

Shortcuts and Siri

OneMark Capture exposes Capture Region, Run OCR / Smart Redaction, Copy Recognized Text, and Export Redacted Image actions.
These actions open OneMark Capture in the foreground and use the same editor workflow as toolbar and menu commands.
App-local shortcuts include Shift-Command-2, Shift-Command-W, and Shift-Command-F.

Privacy and limits

OCR, Text Summary, Smart Review, and smart redaction are text-only workflows in this release.
They do not detect faces or summarize image pixels, and OCR accuracy depends on the source image.
OneMark Capture does not upload screenshots, recognized text, redacted exports, or AI Handoff bundles to third-party AI services.
AI Handoff bundles are local and inspectable; review recognized-text.txt and prompt.md before uploading them elsewhere.
Capture History is session-local and not a persistent image archive.