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

Decodes graphical code in image once it's found by the detect() method.

Positional Arguments

• self: Evision.QRCodeDetector.t()

• img: Evision.Mat.

  grayscale or color (BGR) image containing graphical code.

• points: Evision.Mat.

  Quadrangle vertices found by detect() method (or some other algorithm).

Return

• retval: string

• straight_code: Evision.Mat.t().

  The optional output image containing binarized code, will be empty if not found.

Returns UTF8-encoded output string or empty string if the code cannot be decoded.

Python prototype (for reference only):

decode(img, points[, straight_code]) -> retval, straight_code

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

Decodes graphical code in image once it's found by the detect() method.

Positional Arguments

• self: Evision.QRCodeDetector.t()

• img: Evision.Mat.

  grayscale or color (BGR) image containing graphical code.

• points: Evision.Mat.

  Quadrangle vertices found by detect() method (or some other algorithm).

Return

• retval: string

• straight_code: Evision.Mat.t().

  The optional output image containing binarized code, will be empty if not found.

Returns UTF8-encoded output string or empty string if the code cannot be decoded.

Python prototype (for reference only):

decode(img, points[, straight_code]) -> retval, straight_code

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

Decodes QR code on a curved surface in image once it's found by the detect() method.

Positional Arguments

• self: Evision.QRCodeDetector.t()

• img: Evision.Mat.

  grayscale or color (BGR) image containing QR code.

• points: Evision.Mat.

  Quadrangle vertices found by detect() method (or some other algorithm).

Return

• retval: String

• straight_qrcode: Evision.Mat.t().

  The optional output image containing rectified and binarized QR code

Returns UTF8-encoded output string or empty string if the code cannot be decoded.

Python prototype (for reference only):

decodeCurved(img, points[, straight_qrcode]) -> retval, straight_qrcode

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

Decodes QR code on a curved surface in image once it's found by the detect() method.

Positional Arguments

• self: Evision.QRCodeDetector.t()

• img: Evision.Mat.

  grayscale or color (BGR) image containing QR code.

• points: Evision.Mat.

  Quadrangle vertices found by detect() method (or some other algorithm).

Return

• retval: String

• straight_qrcode: Evision.Mat.t().

  The optional output image containing rectified and binarized QR code

Returns UTF8-encoded output string or empty string if the code cannot be decoded.

Python prototype (for reference only):

decodeCurved(img, points[, straight_qrcode]) -> retval, straight_qrcode

@spec decodeMulti(t(), Evision.Mat.maybe_mat_in(), Evision.Mat.maybe_mat_in()) ::
  {[binary()], [Evision.Mat.t()]} | false | {:error, String.t()}

Decodes graphical codes in image once it's found by the detect() method.

Positional Arguments

• self: Evision.QRCodeDetector.t()

• img: Evision.Mat.

  grayscale or color (BGR) image containing graphical codes.

• points: Evision.Mat.

  vector of Quadrangle vertices found by detect() method (or some other algorithm).

Return

• retval: bool

• decoded_info: [string].

  UTF8-encoded output vector of string or empty vector of string if the codes cannot be decoded.

• straight_code: [Evision.Mat].

  The optional output vector of images containing binarized codes

Python prototype (for reference only):

decodeMulti(img, points[, straight_code]) -> retval, decoded_info, straight_code

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

Decodes graphical codes in image once it's found by the detect() method.

Positional Arguments

• self: Evision.QRCodeDetector.t()

• img: Evision.Mat.

  grayscale or color (BGR) image containing graphical codes.

• points: Evision.Mat.

  vector of Quadrangle vertices found by detect() method (or some other algorithm).

Return

• retval: bool

• decoded_info: [string].

  UTF8-encoded output vector of string or empty vector of string if the codes cannot be decoded.

• straight_code: [Evision.Mat].

  The optional output vector of images containing binarized codes

Python prototype (for reference only):

decodeMulti(img, points[, straight_code]) -> retval, decoded_info, straight_code

@spec detect(t(), Evision.Mat.maybe_mat_in()) ::
  Evision.Mat.t() | false | {:error, String.t()}

Detects graphical code in image and returns the quadrangle containing the code.

Positional Arguments

• self: Evision.QRCodeDetector.t()

• img: Evision.Mat.

  grayscale or color (BGR) image containing (or not) graphical code.

Return

• retval: bool

• points: Evision.Mat.t().

  Output vector of vertices of the minimum-area quadrangle containing the code.

Python prototype (for reference only):

detect(img[, points]) -> retval, points

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

Detects graphical code in image and returns the quadrangle containing the code.

Positional Arguments

• self: Evision.QRCodeDetector.t()

• img: Evision.Mat.

  grayscale or color (BGR) image containing (or not) graphical code.

Return

• retval: bool

• points: Evision.Mat.t().

  Output vector of vertices of the minimum-area quadrangle containing the code.

Python prototype (for reference only):

detect(img[, points]) -> retval, points

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

Both detects and decodes graphical code

Positional Arguments

• self: Evision.QRCodeDetector.t()

• img: Evision.Mat.

  grayscale or color (BGR) image containing graphical code.

Return

• retval: string

• points: Evision.Mat.t().

  optional output array of vertices of the found graphical code quadrangle, will be empty if not found.

• straight_code: Evision.Mat.t().

  The optional output image containing binarized code

Python prototype (for reference only):

detectAndDecode(img[, points[, straight_code]]) -> retval, points, straight_code

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

Both detects and decodes graphical code

Positional Arguments

• self: Evision.QRCodeDetector.t()

• img: Evision.Mat.

  grayscale or color (BGR) image containing graphical code.

Return

• retval: string

• points: Evision.Mat.t().

  optional output array of vertices of the found graphical code quadrangle, will be empty if not found.

• straight_code: Evision.Mat.t().

  The optional output image containing binarized code

Python prototype (for reference only):

detectAndDecode(img[, points[, straight_code]]) -> retval, points, straight_code

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

Both detects and decodes QR code on a curved surface

Positional Arguments

• self: Evision.QRCodeDetector.t()

• img: Evision.Mat.

  grayscale or color (BGR) image containing QR code.

Return

• retval: string

• points: Evision.Mat.t().

  optional output array of vertices of the found QR code quadrangle. Will be empty if not found.

• straight_qrcode: Evision.Mat.t().

  The optional output image containing rectified and binarized QR code

Python prototype (for reference only):

detectAndDecodeCurved(img[, points[, straight_qrcode]]) -> retval, points, straight_qrcode

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

Both detects and decodes QR code on a curved surface

Positional Arguments

• self: Evision.QRCodeDetector.t()

• img: Evision.Mat.

  grayscale or color (BGR) image containing QR code.

Return

• retval: string

• points: Evision.Mat.t().

  optional output array of vertices of the found QR code quadrangle. Will be empty if not found.

• straight_qrcode: Evision.Mat.t().

  The optional output image containing rectified and binarized QR code

Python prototype (for reference only):

detectAndDecodeCurved(img[, points[, straight_qrcode]]) -> retval, points, straight_qrcode

@spec detectAndDecodeMulti(t(), Evision.Mat.maybe_mat_in()) ::
  {[binary()], Evision.Mat.t(), [Evision.Mat.t()]}
  | false
  | {:error, String.t()}

Both detects and decodes graphical codes

Positional Arguments

• self: Evision.QRCodeDetector.t()

• img: Evision.Mat.

  grayscale or color (BGR) image containing graphical codes.

Return

• retval: bool

• decoded_info: [string].

  UTF8-encoded output vector of string or empty vector of string if the codes cannot be decoded.

• points: Evision.Mat.t().

  optional output vector of vertices of the found graphical code quadrangles. Will be empty if not found.

• straight_code: [Evision.Mat].

  The optional vector of images containing binarized codes

• If there are QR codes encoded with a Structured Append mode on the image and all of them detected and decoded correctly, method writes a full message to position corresponds to 0-th code in a sequence. The rest of QR codes from the same sequence have empty string.

Python prototype (for reference only):

detectAndDecodeMulti(img[, points[, straight_code]]) -> retval, decoded_info, points, straight_code

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

Both detects and decodes graphical codes

Positional Arguments

• self: Evision.QRCodeDetector.t()

• img: Evision.Mat.

  grayscale or color (BGR) image containing graphical codes.

Return

• retval: bool

• decoded_info: [string].

  UTF8-encoded output vector of string or empty vector of string if the codes cannot be decoded.

• points: Evision.Mat.t().

  optional output vector of vertices of the found graphical code quadrangles. Will be empty if not found.

• straight_code: [Evision.Mat].

  The optional vector of images containing binarized codes

• If there are QR codes encoded with a Structured Append mode on the image and all of them detected and decoded correctly, method writes a full message to position corresponds to 0-th code in a sequence. The rest of QR codes from the same sequence have empty string.

Python prototype (for reference only):

detectAndDecodeMulti(img[, points[, straight_code]]) -> retval, decoded_info, points, straight_code

@spec detectMulti(t(), Evision.Mat.maybe_mat_in()) ::
  Evision.Mat.t() | false | {:error, String.t()}

Detects graphical codes in image and returns the vector of the quadrangles containing the codes.

Positional Arguments

• self: Evision.QRCodeDetector.t()

• img: Evision.Mat.

  grayscale or color (BGR) image containing (or not) graphical codes.

Return

• retval: bool

• points: Evision.Mat.t().

  Output vector of vector of vertices of the minimum-area quadrangle containing the codes.

Python prototype (for reference only):

detectMulti(img[, points]) -> retval, points

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

Detects graphical codes in image and returns the vector of the quadrangles containing the codes.

Positional Arguments

• self: Evision.QRCodeDetector.t()

• img: Evision.Mat.

  grayscale or color (BGR) image containing (or not) graphical codes.

Return

• retval: bool

• points: Evision.Mat.t().

  Output vector of vector of vertices of the minimum-area quadrangle containing the codes.

Python prototype (for reference only):

detectMulti(img[, points]) -> retval, points

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

QRCodeDetector

Return

• self: Evision.QRCodeDetector.t()

Python prototype (for reference only):

QRCodeDetector() -> <QRCodeDetector object>

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

sets the epsilon used during the horizontal scan of QR code stop marker detection.

Positional Arguments

• self: Evision.QRCodeDetector.t()

• epsX: double.

  Epsilon neighborhood, which allows you to determine the horizontal pattern of the scheme 1:1:3:1:1 according to QR code standard.

Return

• retval: Evision.QRCodeDetector.t()

Python prototype (for reference only):

setEpsX(epsX) -> retval

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

sets the epsilon used during the vertical scan of QR code stop marker detection.

Positional Arguments

• self: Evision.QRCodeDetector.t()

• epsY: double.

  Epsilon neighborhood, which allows you to determine the vertical pattern of the scheme 1:1:3:1:1 according to QR code standard.

Return

• retval: Evision.QRCodeDetector.t()

Python prototype (for reference only):

setEpsY(epsY) -> retval

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

use markers to improve the position of the corners of the QR code

Positional Arguments

• self: Evision.QRCodeDetector.t()
• useAlignmentMarkers: bool

Return

• retval: Evision.QRCodeDetector.t()

alignmentMarkers using by default

Python prototype (for reference only):

setUseAlignmentMarkers(useAlignmentMarkers) -> retval