@spec create() :: t() | {:error, String.t()}

Creates an instance of the OCRTesseract class. Initializes Tesseract.

Keyword Arguments

• datapath: c_string.

  the name of the parent directory of tessdata ended with "/", or NULL to use the system's default directory.

• language: c_string.

  an ISO 639-3 code or NULL will default to "eng".

• char_whitelist: c_string.

  specifies the list of characters used for recognition. NULL defaults to "" (All characters will be used for recognition).

• oem: int.

  tesseract-ocr offers different OCR Engine Modes (OEM), by default tesseract::OEM_DEFAULT is used. See the tesseract-ocr API documentation for other possible values.

• psmode: int.

  tesseract-ocr offers different Page Segmentation Modes (PSM) tesseract::PSM_AUTO (fully automatic layout analysis) is used. See the tesseract-ocr API documentation for other possible values.

Return

• retval: OCRTesseract

Note: The char_whitelist default is changed after OpenCV 4.7.0/3.19.0 from "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ" to "".

Python prototype (for reference only):

create([, datapath[, language[, char_whitelist[, oem[, psmode]]]]]) -> retval

@spec create([{atom(), term()}, ...] | nil) :: t() | {:error, String.t()}

Creates an instance of the OCRTesseract class. Initializes Tesseract.

Keyword Arguments

• datapath: c_string.

  the name of the parent directory of tessdata ended with "/", or NULL to use the system's default directory.

• language: c_string.

  an ISO 639-3 code or NULL will default to "eng".

• char_whitelist: c_string.

  specifies the list of characters used for recognition. NULL defaults to "" (All characters will be used for recognition).

• oem: int.

  tesseract-ocr offers different OCR Engine Modes (OEM), by default tesseract::OEM_DEFAULT is used. See the tesseract-ocr API documentation for other possible values.

• psmode: int.

  tesseract-ocr offers different Page Segmentation Modes (PSM) tesseract::PSM_AUTO (fully automatic layout analysis) is used. See the tesseract-ocr API documentation for other possible values.

Return

• retval: OCRTesseract

Note: The char_whitelist default is changed after OpenCV 4.7.0/3.19.0 from "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ" to "".

Python prototype (for reference only):

create([, datapath[, language[, char_whitelist[, oem[, psmode]]]]]) -> retval

@spec run(t(), Evision.Mat.maybe_mat_in(), integer()) ::
  binary() | {:error, String.t()}

Recognize text using the tesseract-ocr API.

Positional Arguments

• self: Evision.Text.OCRTesseract.t()

• image: Evision.Mat.t().

  Input image CV_8UC1 or CV_8UC3

• min_confidence: int

Keyword Arguments

• component_level: int.

  OCR_LEVEL_WORD (by default), or OCR_LEVEL_TEXTLINE.

Return

• retval: String

Takes image on input and returns recognized text in the output_text parameter. Optionally provides also the Rects for individual text elements found (e.g. words), and the list of those text elements with their confidence values.

Python prototype (for reference only):

run(image, min_confidence[, component_level]) -> retval

@spec run(t(), Evision.Mat.maybe_mat_in(), integer(), [{atom(), term()}, ...] | nil) ::
  binary() | {:error, String.t()}

@spec run(t(), Evision.Mat.maybe_mat_in(), Evision.Mat.maybe_mat_in(), integer()) ::
  binary() | {:error, String.t()}

Variant 1:

run

Positional Arguments

• self: Evision.Text.OCRTesseract.t()
• image: Evision.Mat.t()
• mask: Evision.Mat.t()
• min_confidence: int

Keyword Arguments

• component_level: int.

Return

• retval: String

Python prototype (for reference only):

run(image, mask, min_confidence[, component_level]) -> retval

Variant 2:

Recognize text using the tesseract-ocr API.

Positional Arguments

• self: Evision.Text.OCRTesseract.t()

• image: Evision.Mat.t().

  Input image CV_8UC1 or CV_8UC3

• min_confidence: int

Keyword Arguments

• component_level: int.

  OCR_LEVEL_WORD (by default), or OCR_LEVEL_TEXTLINE.

Return

• retval: String

Takes image on input and returns recognized text in the output_text parameter. Optionally provides also the Rects for individual text elements found (e.g. words), and the list of those text elements with their confidence values.

Python prototype (for reference only):

run(image, min_confidence[, component_level]) -> retval

@spec run(
  t(),
  Evision.Mat.maybe_mat_in(),
  Evision.Mat.maybe_mat_in(),
  integer(),
  [{atom(), term()}, ...] | nil
) :: binary() | {:error, String.t()}

run

Positional Arguments

• self: Evision.Text.OCRTesseract.t()
• image: Evision.Mat.t()
• mask: Evision.Mat.t()
• min_confidence: int

Keyword Arguments

• component_level: int.

Return

• retval: String

Python prototype (for reference only):

run(image, mask, min_confidence[, component_level]) -> retval

@spec setWhiteList(t(), binary()) :: t() | {:error, String.t()}

setWhiteList

Positional Arguments

• self: Evision.Text.OCRTesseract.t()
• char_whitelist: String

Python prototype (for reference only):

setWhiteList(char_whitelist) -> None