Everything you need to know about the Image Markup Tool.
How do I capture a screenshot?+
Click the "Capture Screenshot" button on the upload screen. Your browser will prompt you to select a window, tab, or your entire screen. Once you confirm, the screenshot is immediately loaded into the canvas editor — no server upload, no data leaves your device. This uses the navigator.mediaDevices.getDisplayMedia API supported in modern browsers.
Can I edit existing annotations?+
Yes. Use the Select tool (press V or click the arrow icon) and click any annotation on the canvas. Once selected, you can drag it, resize it using the handles, and change its properties in the Properties panel on the right. Double-clicking a text object lets you edit the text inline.
What is the blur tool?+
The blur/redact tool lets you draw a rectangular region over sensitive content — like passwords, emails, or personal info — and that region gets visually blurred on the canvas. It uses an offscreen canvas to sample the underlying image pixels and apply a box-blur filter, then embeds the result as a Fabric.js image object. The blur region can be moved and resized like any other annotation.
How do layers work?+
Every object you add (arrow, shape, text, emoji, blur) appears as a layer in the Layers panel on the right. You can click a layer to select it on the canvas, adjust its opacity individually, lock it to prevent accidental editing, or delete it. Layers are listed top-to-bottom matching canvas draw order — the topmost item in the list is rendered on top of everything else.
Can I export as SVG?+
Yes. Click the "SVG" export button. Fabric.js serialises the entire canvas — including your annotations — to SVG markup, which is downloaded as a .svg file. SVG export preserves vector shapes and text as crisp scalable elements. Note: blur regions and the background image are embedded as raster data within the SVG.
How do I use keyboard shortcuts?+
Press ? at any time to open the keyboard shortcuts overlay. Key shortcuts include: V Select, A Arrow, R Rectangle, C Circle, L Line, T Text, B Blur, E Emoji, Ctrl+Z Undo, Ctrl+Shift+Z Redo, Delete Delete selected, +/- Zoom.