Getting the blank sheet back
Teachers want a clean copy of a worksheet that only survives as a filled-in photo. Parents want their child to practise the same page again. Students want to redo their notes without last week's answers in the way. In every case the job is the same: take away the handwriting and keep everything that was printed — the questions, the boxes, the ruled lines — exactly as it was. An object eraser is the wrong tool for that, because it rebuilds each area from its surroundings and has no idea what paper is. This mode does know: it treats the page as paper with marks on it.
Step one: a model of the paper
Before any stroke is touched, the editor estimates how bright the paper is everywhere on the page. It divides the photo into small cells, takes the brighter majority of each cell (ink is a minority of almost any cell), and smooths the result across neighbouring cells. The outcome is a gently varying brightness field: brighter where the lamp was, darker in the corner your hand shaded. When strokes are later replaced, they are replaced with the paper as it looks at that exact spot, so a rebuilt answer does not show up as a too-white patch on a page that was photographed under a yellow lamp.
Step two: one click, every matching stroke
Click any handwritten stroke. The editor measures its ink colour — relative to the paper under it, so a shadow does not change the answer — and its stroke width, then proposes every other mark that shares them. Faint or thin parts of the same pen drift towards grey, so a coloured pen is matched by the direction of its colour as well as its strength. A blue ballpoint, a black gel pen and a pencil each come out as their own group; shift-click to add another.
Printed text is left out by default. Printed letters sit on one straight baseline with even heights; hands wobble. The editor groups each mark with its neighbours on the same line and checks how straight their baseline is and how even their heights are. If you do want printed text gone too, tick Include printed text. If you click printed text with the option off, the editor tells you rather than selecting it.
Step three: rebuild the paper and the lines
Rebuild paper replaces the selected pixels — grown by a pixel and a half to take the soft edge of the ink — with the paper model plus the page's own fine grain, measured from untouched paper nearby. Ruled lines and grid lines are found as rows or columns that carry a long line across most of the page; where an erased stroke crossed one, that line is continued in its own colour, so the answer disappears and the line underneath comes back unbroken. Nothing is sent to an AI model, nothing is downloaded, and every pixel outside the selection is copied through exactly.
When it needs your help
Writing that runs straight over printed text cannot be separated by colour alone if the pen and the print are the same black; select those strokes with the brush instead. Very faint pencil may need a second click on a darker part of the line. Heavy creases and shadows across the page are not ink and are left alone — straighten and flatten the page before you photograph it, or use Remove shadow from photo first. For stray marks that are not writing at all — a coffee ring, a sticker — Remove unwanted objects is the better tool.
For your own pages
This is for your own worksheets, notes and practice sheets. It is not for certificates, mark sheets, forms, receipts or any official document, and it must not be used to alter one.