Additional Flags

These flags were designed to improve the quality of the segmentation on idiosyncratic but very common classes of documents. They may be redundant with other options (e.g. high-variation-foreground) or trigger heuristics whose impact has not been evaluated on all types of documents (background-floss). Their systematic usage is not encouraged.

 

high-variation-foreground

This flag is redundant when block-size=8.

Option type

Boolean

Default

False

Command line

No

Expert

Normally, it is assumed that over a width of 16 pixels, the foreground color does not vary too much.

However, this is not true in the following cases:

Characters in the neighboring words have very different colors

A character is next to a vertical line of different color

 

subsample-refine

Smooths the foreground and background layers to improve the overall appearance of the image. Using this option increases the time it takes to encode the image. Add refinements (such as interpolation heuristics) to foreground and background subsampling.

Option type

Boolean

Default

False

Command line

Yes

 

background-floss

Minimizes the blurring of text in a document by displaying background color in small intervals between adjacent characters. Generally causes larger files and less smooth background. Necessary when characters are thick (typically when upsampling).

Option type

Boolean

Default

False

Command line

No