Cropping and Overlays

Choosing what of each page ends up on screen.

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A scanned page is rarely the shape of a video frame. Cropping is how you pick the part that matters — a single column, one staff system, one cell of a sprite sheet — and it happens in the preview, above the timeline.

Crop rectangles

Drag across the preview to draw a rectangle. Drag inside it to move it, or take an edge or a corner to resize. Esc clears it.

Nothing has changed yet: the rectangle is a proposal. ReturnCrop to Selection — is what commits it, replacing the item with the cropped result.

You can draw more than one rectangle on a page. Each becomes its own item when the crops are applied, in the order they sit on the page, which is what turns a page of several columns into several timeline items.

To undo a crop, use Remove crop from the preview's context menu. The original is kept, so nothing is lost by cropping — the full page comes back.

If the edges feel fiddly to grab, Settings has Expand crop-rect resize zones beyond the rectangle's edges, which widens the target area without changing the rectangle.

Reusing a crop

Scanned pages tend to want the same crop over and over, so a rectangle can be copied from one page to the next rather than redrawn.

CommandWhat it does
CCopies the rectangles on this page — all of them, not just one.
XCopies and removes them.
VPastes onto the current page.
Apply Crop to AllApplies the current crop rectangles on every page in the project at once.

Paste, and Paste Row First

Pasting does not drop the rectangle on top of what is already there. If the page already has rectangles, the pasted one is placed beside them, in the first free space it finds.

The two paste commands differ only in which direction it tries first:

CommandLooks for space
V — PasteBelow first, then right, then above, then left.
V — Paste Row FirstRight first, then below, then above, then left.

So a page read in columns is built up with plain paste, and a page read in rows — a sprite sheet, a grid of panels — with Paste Row First. Paste is ignored on a page that is already cropped.

Inset and outset

Inset / Outset Crop Rects, in the preview's context menu, grows or shrinks every rectangle at once. Useful when a batch of crops all came out a little tight, or all take in a few millimetres of scanner shadow.

It takes a horizontal and a vertical amount, in pixels, as a percentage of the source image, or as a percentage of each rectangle. There is also a horizontal and vertical offset, for shifting rather than resizing.

Staged and applied

Rectangles are staged until you commit them. That is what lets the detection tools propose crops across a whole project without changing anything, and lets you look before agreeing.

Finding the crops for you

Three tools in the Tools menu work out the rectangles themselves and stage them for review.

Smart Text Crop

Reads the text on every uncropped page and stages crops around it, so a video can follow a narration a paragraph or a line at a time rather than a page at a time.

ModeWhat it produces
ParagraphsOne crop per detected paragraph.
SegmentsA set number of blocks per page, the splits snapping to paragraph boundaries.
LinesEvery N lines, either flowing across paragraph breaks or respecting them.

Three further settings decide the shape of each crop rather than where it falls:

Split into Grid

For a page that is a grid: a sprite sheet, a contact sheet, a page of panels. Give it rows and columns, and an outer margin and gutter as percentages, and it stages a rectangle per cell for you to adjust before committing.

Split into Staff Systems

Finds the staff systems on a score and crops each out — covered in full on the sheet music page.

All three skip pages that are already cropped, and all three remember their settings with the project rather than across projects, so a book and a score can keep different answers.

Overlays

An overlay is a coloured rectangle drawn over the page rather than a cut taken out of it — for covering something up. An answer in a workbook, a name on a scanned document, a watermark you would rather not show.

Hold and drag to draw one. The gesture is the same one that draws a crop rectangle, and is what tells the two apart.

Right-click an overlay for Change Color, which takes any colour and any opacity, or Remove Overlay. -click adds an overlay to the selection or takes it out again, so several can be recoloured or removed in one go.

Overlays belong to the page, so cropping a page that carries one clips the overlay along with everything else.

Overlays and crop rectangles share the same drag gestures, so ClapperBoard only lets you work on one at a time: while any crop rectangle exists on the page, overlays cannot be grabbed. Press Esc to clear the rectangle first, and the overlays become editable again.

Last updated August 15, 2026