alto (analyzed layout and text object) stores layout information and OCR recognized text of books an journals. Styles define properties of layout elements. A style defined in a parent element is used as the default for all its children. A text style defines font properties of text. A paragraph style defines formatting properties of text blocks. The root layout element. One page of a book or journal. The area between the top line of print and the upper edge of the leaf. It may contain page number or running title. That margin of a page adjacent to the binding edge of a book. The space between the text and the outer extremity of the leaf of a book. May contain margin notes. The area between the bottom line of letterpress or writing and the bottom edge of the leaf. It may contain a page number, a signature number or a catch word. Rectangle surrounding the printed area of a page. Page number and running title are not part of the print space. Group of available block types A block of text. A picture or image. A graphic used to separate blocks. Usually a line or rectangle. A block that consists of other blocks Base type for any kind of block on the page. Tells the rotation of the block e.g. text or illustration. The value is in degree counterclockwise. The reading sequence of blocks on the page. Type of the substitution (if any). May be something like hyphenation, or ocr correction Content of the substiutrion. Something like the corrected ocr text or the un hyphenated word Word Confidence: Confidence level of the ocr for this string. A value between 0 and 9 Confidence level of each character in that string. A list of numbers, one number between 0 and 9 for each character A region on a page A list of points Describes the bounding shape of a block, if it is not rectangular. A polygon shape. An ellipse shape. A circle shape. A block that consists of other blocks A user defined string to identify the type of composed block (e.g. table, advertisement, ...) A link to an image which contains only the composed block. A picture or image. A user defined string to identify the type of illustration like photo, map, drawing, chart, ... A link to an image which contains only the illustration. A graphic used to separate blocks. Usually a line or rectangle. A block of text. A single line of text. A white space. A hyphenation char. Can appear only at the end of a line.