OCRParams Class Documentation

class OCRParams

Namespace:com::datalogics::PDFL

Detailed Description

Parameters for configuring the OCR (Optical Character Recognition) engine. OCRParams controls settings such as the engine to use, the resolution of the input images, the language(s) to recognize, performance tuning, page segmentation mode, candidate font names for placing text, and image preprocessing options.

Referenced by

Uses types

Constructor & Destructor Documentation

OCRParams

OCRParams()

Create an OCRParams structure with defaults.

Member Function Documentation

delete

synchronized void delete(Boolean disposing)

Parameters

disposing: Boolean

Returns:

synchronized void

delete

synchronized void delete()

Returns:

synchronized void

finalize

void finalize()

Returns:

void

getCandidateFontNames

java.util.List< String > getCandidateFontNames()

Returns:

java.util.List< String >

The names of candidate fonts for placing text under an image. The default list should work well in most cases. If you're using text that isn't represented by Latin fonts, or by Chinese, Japanese, or Korean fonts, then retrieve this list, add the font that can represent that text, then set that new list on this object.

Enough font names must be supplied to cover the expected languages/scripts in use.

The code selects a font to represent each word. If a word code-switches between different scripts, for instance, if it contains non-Latin text and Arabic numerals, then make sure to supply the name of a font family that can handle both the text and the numerals.

The quality of the results depends on the font choice. The list is searched in order until a font works for a particular word. To make the text fit better, it's recommended to list proportional fonts before fixed-width fonts. Decorative fonts with flourishes, like Zapf Chancery, deliver poor results. Generally, supply a font that would be used in block text, such as in a newspaper or work of literature, such as Times Roman, or a font already in the list, like MinionPro.

If the PlaceTextUnder method in OCREngine can't identify a font that covers the whole text of a word, an exception will be thrown.

getConfigurationParameters

java.util.Map< String, String > getConfigurationParameters()

Returns:

java.util.Map< String, String >

Get the configuration parameters. Note: Reserved for internal use. Do not use unless directed to by Datalogics Support.

getEnableImagePreprocessing

boolean getEnableImagePreprocessing()

Returns:

boolean

Get the image preprocessing enable state.True if any image preprocessing is on.

getEngine

String getEngine()

Returns:

String

The name of the OCR engine to use. Use the Tesseract4Engine constant to select the Tesseract v4 engine.

getPageSegmentationMode

PageSegmentationMode getPageSegmentationMode()

Returns:

PageSegmentationMode

The page segmentation mode, which controls how the OCR engine detects text regions on the page.

getPerformance

Performance getPerformance()

Returns:

Performance

The desired performance mode for the OCR engine, balancing speed versus accuracy.

getResolution

double getResolution()

Returns:

double

The resolution, in DPI, at which images are rendered for OCR processing.

getTesseract4Engine

static String getTesseract4Engine()

Returns:

String

The name of the Tesseract v4 engine. Pass this value to the Engine property to select the Tesseract v4 engine.

setCandidateFontNames

void setCandidateFontNames(java.util.List< String > candidateFonts)

Parameters

candidateFonts: java.util.List< String >

Returns:

void

The names of candidate fonts for placing text under an image. The default list should work well in most cases. If you're using text that isn't represented by Latin fonts, or by Chinese, Japanese, or Korean fonts, then retrieve this list, add the font that can represent that text, then set that new list on this object.

Enough font names must be supplied to cover the expected languages/scripts in use.

The code selects a font to represent each word. If a word code-switches between different scripts, for instance, if it contains non-Latin text and Arabic numerals, then make sure to supply the name of a font family that can handle both the text and the numerals.

The quality of the results depends on the font choice. The list is searched in order until a font works for a particular word. To make the text fit better, it's recommended to list proportional fonts before fixed-width fonts. Decorative fonts with flourishes, like Zapf Chancery, deliver poor results. Generally, supply a font that would be used in block text, such as in a newspaper or work of literature, such as Times Roman, or a font already in the list, like MinionPro.

If the PlaceTextUnder method in OCREngine can't identify a font that covers the whole text of a word, an exception will be thrown.

setConfigurationParameters

void setConfigurationParameters(java.util.Map< String, String > configurationParams)

Parameters

configurationParams: java.util.Map< String, String >

Returns:

void

Set the configuration parameters. Note: Reserved for internal use. Do not use unless directed to by Datalogics Support.

setEnableImagePreprocessing

void setEnableImagePreprocessing(boolean enable)

Parameters

enable: boolean

Returns:

void

Enable all image preprocessing, default enabled.Note that once the OCREngine is initialized, this setting is permanent.

setEngine

void setEngine(String value)

Parameters

value: String

Returns:

void

The name of the OCR engine to use. Use the Tesseract4Engine constant to select the Tesseract v4 engine.

setPageSegmentationMode

void setPageSegmentationMode(PageSegmentationMode mode)

Parameters

mode: PageSegmentationMode

Returns:

void

The page segmentation mode, which controls how the OCR engine detects text regions on the page.

setPerformance

void setPerformance(Performance performanceSetting)

Parameters

performanceSetting: Performance

Returns:

void

The desired performance mode for the OCR engine, balancing speed versus accuracy.

setResolution

void setResolution(double value)

Parameters

value: double

Returns:

void

The resolution, in DPI, at which images are rendered for OCR processing.