Tree of hypotheses

When matching each layout alternative with an image, the program successively generates hypotheses for each of the elements. Hypotheses for the elements are generated one by one: from the first (topmost) element in the tree to the last (bottom) element. From the generated hypotheses, a tree of hypotheses is built. If the layout alternative is successfully matched with the image the tree of hypotheses is displayed in the Hypotheses window. If more than one layout alternative match the image, the tree of hypotheses for the first alternative is displayed. If none of the alternatives can match the image, the tree of hypotheses for the first alternative is displayed.

Note.The number of hypotheses created for an element may exceed the number set in the Number of surviving hypotheses field. In this case, only the user-defined number of the best hypotheses will make it into the tree of hypotheses.

In the tree of hypotheses, the program will then look for thebest path, i.e. the best-quality path to the hypotheses of the last element. The quality of the path is calculated by multiplying the hypotheses for the elements in this path.

The hypotheses in the best path are used to detect the blocks.

The tree of hypotheses is displayed in the Hypotheses window. To view the tree of hypotheses for a particular image:

Open the image.
Match the FlexiLayout with the image (select Match from the FlexiLayout menu or from the shortcut menu).

To view the hypotheses for elements which are part of a Group element:

Select the hypothesis for the Group element.
Press Enter or select the Show Details command from the shortcut menu.

To go one level up, press Ctrl+Enter or select the Go One Level Up command from the shortcut menu.

Note.The tree of hypotheses built for the current image is deleted when you close that image. The best path (the chain of hypotheses that was used to build the Matched Layout) is preserved. You can view these hypotheses when you open the image again. The program does not store the entire tree of hypotheses, because it may take up too much memory.

The tree of hypotheses consists of the following parts:

The left-hand column contains the elements of the first nesting level in the order in which they go in the FlexiLayout tree.

The right-hand column contains hypotheses generated for each of the elements. Each hypotheses is marked with an icon. The hypotheses are joined by thin lines which show the order in which they were generated. The hypotheses in the best path are joined by green lines, other hypotheses are joined by gray lines.

Icon	Description
	A hypothesis from the best path.
	A hypothesis not from the best path.
	A null hypothesis from the best path.
	A null hypothesis not from the best path.
	An incomplete chain of hypotheses for a Group element (Group, Repeating Group, Header, Footer). You can view an incomplete chain of hypotheses to locate a non-detected element.
,,,	The branch of the element displays the hypothesis from the best path. To view all the hypotheses, press "+" or select Expand Active in the shortcut menu.
,,,	Displays all the hypotheses in the branch of the element. To hide the hypotheses which are not from the best path, press "-" or select Collapse Active in the shortcut menu.
,,,,	The sub-branch of hypotheses for the element was discontinued at this point.