Asprise OCR Property Summary¶

You use properties to control the OCR process. Below is summary of all properties supported:

General Properties¶

Property	Description	Values	Default value
PROP_PAGE_TYPE	To provide hint to the OCR engine about the document type. If the input document is simple, use single_block.	auto \| single_block \| single_column \| single_line \| single_word \| single_char \| scattered	auto
PROP_LIMIT_TO_CHARSET	Use it if the image contains only a limit set of characters, e.g, numbers. May significantly speed up the OCR process.	e.g., '0123456789'	(all characters)
PROP_OUTPUT_SEPARATE_WORDS	By default OCR outputs line as blocks. Set to true to use word as block unit.	true \| false	false
PROP_INPUT_PDF_DPI	DPI for rendering input images if the input file is in PDF format. Change to a higher value if texts are small.	e.g., 300, 350, 400	300

Property	Description	Values	Default value
START_PROP_DICT_CUSTOM_DICT_FILE	User defined dictionary	(a text file with a word in each line)	(null)
START_PROP_DICT_CUSTOM_TEMPLATES_FILE	User defined templates	(a text file with a tempate in each line)	(null)
PROP_DICT_DICT_IMPORTANCE	Percentage measuring the importance of the dictionary	0-100	10

Property	Description	Values	Default value
PROP_PDF_OUTPUT_FILE	Target PDF output file - required	<Path to file>	(null)
PROP_PDF_OUTPUT_RETURN_TEXT	Request the OCR engine to return result in other formats when output is set to pdf.	text \| xml	(null)
PROP_PDF_OUTPUT_TEXT_VISIBLE	Whether text should be highlighted in color	true \| false	false
PROP_PDF_OUTPUT_IMAGE_FORCE_BW	Reduce PDF file size by embedding black/white version of the input images	true \| false	true
PROP_PDF_OUTPUT_PDFA	Output PDF/A ISO 19005-1:2005 instead of normal PDF.	true \| false	false
PROP_PDF_OUTPUT_PDFA_FONT_FILE	Optionally specify the TTF font to be embedded in PDA/A	<Path to TTF file>	(null)

Property	Description	Values	Default value
PROP_RTF_OUTPUT_FILE	Target RTF output file - required	<Path to file>	(null)
PROP_RTF_OUTPUT_RETURN_TEXT	Request the OCR engine to return result in other formats when output is set to rtf.	text \| xml	(null)
PROP_RTF_PAPER_SIZE	Change the default paper size	LETTER \| A4	LETTER

Property	Description	Values	Default value
PROP_TABLE_SKIP_DETECTION	Whether table detection should be skipped	true \| false	false
PROP_TABLE_MIN_SIDE_LENGTH	Minimum cell height when detecting tables	(in pixels)	32
PROP_SAVE_INTERMEDIATE_IMAGES_TO_DIR	Save intermediate images generated for debug purpose	<Path to folder>	(null)

Property	Description	Values	Default value
PROP_IMG_PREPROCESS_TYPE	How image should be pre-processed	default \| default_with_orientation_detection \| custom	default
PROP_IMG_PREPROCESS_CUSTOM_CMDS	Must specify the commands if preprocess type is set to custom	e.g., 'scale(2);invert();default()'	(null)

Function	Description
scale(value)	Scales the image up or down
rotate(degrees)	Rotates the image
crop(x, y, width, height)	Crops the image
deskew([maxDegrees])	Deskew the image - optionally you can specify the max degrees
grayscale()	Converts the image to grayscale
invert()	Color inverts the image
sharpen([filterHalfWidth, fractionOfEdge])	Sharpens the image (for gray/color images) - optionally specify the sharpen params
bgNorm([reduction, size, bgValue])	Normalizes background (gray/color) - optionally specify the normalization params
contrastNorm([size, minDiff, smooth])	Normalizes contrast (gray only) - optionally specify the normalization params
detectEdge([horizontal, vertical])	Detects edge (gray only) - optionally specify the params
bin1([windowHalfWidth, factor, subdivisions])	Binarizes gray images into binrary (black/white) - optional params
autoRotate([confThreshold])	Auto rotates page (binary only) - deskew and binarize images first