Screenshot Markup Studio is a desktop screenshot annotation, vector callout, and presentation framing utility for Linux. Designed as a clean, offline-first markup workspace, it lets you annotate captures with arrows, numbered step badges, highlight boxes, text pills, and pixelate or Gaussian blur masking regions before exporting in multiple formats.

Key Features:

• Vector Callout Canvas: Draw crisp arrows with arrowheads, auto-numbered step badges (1, 2, 3...), rounded highlight rectangles, pill-backed text labels, and pixelate or Gaussian blur masking regions over any loaded screenshot.
• Social Frame & Gradient Backdrop: Wrap annotated images with rounded corners, soft drop shadows, custom solid or gradient canvas padding, optional window titlebar dots, and a URL caption bar.
• Layer Queue & Multi-Format Export: Manage every annotation layer in an ordered list, save and reload editable JSON annotation projects, and export at full resolution to PNG, JPEG, WebP, and PDF.

Disclaimer: Screenshot Markup Studio is an independent open-source project by TC Studio and is not affiliated with, endorsed by, or sponsored by Greenshot.