Package org.apache.tika.parser.ocr

Class TesseractOCRConfig

  • All Implemented Interfaces:
    Serializable
    public class TesseractOCRConfig
extends Object
implements Serializable
    Configuration for TesseractOCRParser. This class is not thread safe and must be synchronized externally.

    This class will remember all set* field forever, and on cloneAndUpdate(TesseractOCRConfig), it will update all the fields that have been set on the "update" config. So, for example, if you want to change language to "fra" from "eng" and then on another parse, you want to change depth to 5 on the same update object, but you expect the language to revert to "eng", you'll be wrong. Create a new update config for each parse unless you're only changing the same field(s) with every parse.

    See Also:
    Serialized Form

    • Constructor Detail

      • TesseractOCRConfig

        public TesseractOCRConfig()

    • Method Detail

      • getLangs

        public static void getLangs​(String language,
                            Set<String> validLangs,
                            Set<String> invalidLangs)
        This takes a language string, parses it and then bins individual langs into valid or invalid based on regexes against the language codes
        Parameters:
        language -
        validLangs -
        invalidLangs -

      • setLanguage

        public void setLanguage​(String languageString)
        Set tesseract language dictionary to be used. Default is "eng". languages are either:
        1. Nominally an ISO-639-2 code but compound codes are allowed separated by underscore: e.g., chi_tra_vert, aze_cyrl
        2. A file path in the script directory. The name starts with upper-case letter. Some of them have underscores and other upper-case letters: e.g., script/Arabic, script/HanS_vert, script/Japanese_vert, script/Canadian_Aboriginal
        Multiple languages may be specified, separated by plus characters. e.g. "chi_tra+chi_sim+script/Arabic"

      • setPageSegMode

        public void setPageSegMode​(String pageSegMode)
        Set tesseract page segmentation mode. Default is 1 = Automatic page segmentation with OSD (Orientation and Script Detection)

      • setPageSeparator

        public void setPageSeparator​(String pageSeparator)
        The page separator to use in plain text output. This corresponds to Tesseract's page_separator config option. The default here is the empty string (i.e. no page separators). Note that this is also the default in Tesseract 3.x, but in Tesseract 4.0 the default is to use the form feed control character. We are overriding Tesseract 4.0's default here.
        Parameters:
        pageSeparator -

      • setTrustedPageSeparator

        public void setTrustedPageSeparator​(String pageSeparator)
        Same as setPageSeparator(String) but does not perform any checks on the string.
        Parameters:
        pageSeparator -

      • isPreserveInterwordSpacing

        public boolean isPreserveInterwordSpacing()
        Returns:
        whether or not to maintain interword spacing.

      • setPreserveInterwordSpacing

        public void setPreserveInterwordSpacing​(boolean preserveInterwordSpacing)
        Whether or not to maintain interword spacing. Default is false.
        Parameters:
        preserveInterwordSpacing -

      • setMinFileSizeToOcr

        public void setMinFileSizeToOcr​(long minFileSizeToOcr)
        Set minimum file size to submit file to ocr. Default is 0.

      • setMaxFileSizeToOcr

        public void setMaxFileSizeToOcr​(long maxFileSizeToOcr)
        Set maximum file size to submit file to ocr. Default is Integer.MAX_VALUE.

      • setTimeoutSeconds

        public void setTimeoutSeconds​(int timeoutSeconds)
        Set maximum time (seconds) to wait for the ocring process to terminate. Default value is 120s.

      • setOutputType

        public void setOutputType​(String outputType)

      • setEnableImagePreprocessing

        public void setEnableImagePreprocessing​(boolean enableImagePreprocessing)
        Set the value to true if processing is to be enabled. Default value is false.

      • getDensity

        public int getDensity()
        Returns:
        the density

      • setDensity

        public void setDensity​(int density)
        Parameters:
        density - the density to set. Valid range of values is 150-1200. Default value is 300.

      • getDepth

        public int getDepth()
        Returns:
        the depth

      • setDepth

        public void setDepth​(int depth)
        Parameters:
        depth - the depth to set. Valid values are 2, 4, 8, 16, 32, 64, 256, 4096. Default value is 4.

      • getColorspace

        public String getColorspace()
        Returns:
        the colorspace

      • setColorspace

        public void setColorspace​(String colorspace)
        Parameters:
        colorspace - the colorspace to set Deafult value is gray.

      • getFilter

        public String getFilter()
        Returns:
        the filter

      • setFilter

        public void setFilter​(String filter)
        Parameters:
        filter - the filter to set. Valid values are point, hermite, cubic, box, gaussian, catrom, triangle, quadratic and mitchell. Default value is triangle.

      • isSkipOcr

        public boolean isSkipOcr()

      • setSkipOcr

        public void setSkipOcr​(boolean skipOcr)
        If you want to turn off OCR at run time for a specific file, set this to true
        Parameters:
        skipOcr -

      • getResize

        public int getResize()
        Returns:
        the resize

      • setResize

        public void setResize​(int resize)
        Parameters:
        resize - the resize to set. Valid range of values is 100-900. Default value is 900.

      • isApplyRotation

        public boolean isApplyRotation()
        Returns:
        Whether or not a rotation value should be calculated and passed to ImageMagick before performing OCR.

      • setApplyRotation

        public void setApplyRotation​(boolean applyRotation)
        Sets whether or not a rotation value should be calculated and passed to ImageMagick.
        Parameters:
        applyRotation - to calculate and apply rotation, false to skip. Default is false

      • addOtherTesseractConfig

        public void addOtherTesseractConfig​(String key,
                                    String value)
        Add a key-value pair to pass to Tesseract using its -c command line option. To see the possible options, run tesseract --print-parameters.

        You may also add these parameters in TesseractOCRConfig.properties; any key-value pair in the properties file where the key contains an underscore is passed directly to Tesseract.

        Parameters:
        key -
        value -