When your Banco Comercial Português statement arrives as a scan or a photo of the page rather than a clean export, the numbers on it are just pixels until they are extracted. A statement that has been scanned or photographed is read with OCR. The engine identifies the transaction table inside the image and picks out the date, description, amount and running balance columns line by line. Because every row is verified against the printed closing figure, a misread digit or a blurred character is caught before the data reaches your ledger.
Whatever the running balance looks like on your Banco Comercial Português statement, Convert·Into checks it against the statement's own printed closing figure before you export anything. That verification runs on every statement, not only on imaged pages. The engine recalculates the running balance independently from the extracted transactions and compares the result to the figure printed on the original document. Any row that does not add up is flagged for review, while the rest of the statement is processed normally. This means you never need to check the maths yourself; the file arrives with a clear, auditable trail of where the numbers match the source and where a second look is warranted.