US Bank Check OCR Ruby

The Ruby OCR SDK supports the Bank Check API.

Using the sample below, we are going to illustrate how to extract the data that we want using the OCR SDK.
Bank Check sample


require 'mindee'

# Init a new client
mindee_client = 'my-api-key')

# Load a file from disk
input_source = mindee_client.source_from_path('/path/to/the/file.ext')

# Parse the file
result = mindee_client.parse(

# Print a full summary of the parsed data in RST format
puts result.document

# Print the document-level parsed data
# puts result.document.inference.prediction

Output (RST):

:Mindee ID: b9809586-57ae-4f84-a35d-a85b2be1f2a2
:Filename: default_sample.jpg

:Product: mindee/bank_check v1.0
:Rotation applied: Yes

:Check Issue Date: 2022-03-29
:Amount: 15332.90
:Payees: JOHN DOE
         JANE DOE
:Routing Number:
:Account Number: 7789778136
:Check Number: 0003401

Page Predictions

Page 0
:Check Position: Polygon with 21 points.
:Signature Positions: Polygon with 6 points.
:Check Issue Date: 2022-03-29
:Amount: 15332.90
:Payees: JOHN DOE
         JANE DOE
:Routing Number:
:Account Number: 7789778136
:Check Number: 0003401

Field Types

Standard Fields

These fields are generic and used in several products.

Basic Field

Each prediction object contains a set of fields that inherit from the generic Field class.
A typical Field object will have the following attributes:

  • value (String, Float, Integer, Boolean): corresponds to the field value. Can be nil if no value was extracted.
  • confidence (Float, nil): the confidence score of the field prediction.
  • bounding_box (Mindee::Geometry::Quadrilateral, nil): contains exactly 4 relative vertices (points) coordinates of a right rectangle containing the field in the document.
  • polygon (Mindee::Geometry::Polygon, nil): contains the relative vertices coordinates (Point) of a polygon containing the field in the image.
  • page_id (Integer, nil): the ID of the page, is nil when at document-level.
  • reconstructed (Boolean): indicates whether an object was reconstructed (not extracted as the API gave it).

Aside from the previous attributes, all basic fields have access to a to_s method that can be used to print their value as a string.

Amount Field

The amount field AmountField only has one constraint: its value is a Float (or nil).

Date Field

Aside from the basic Field attributes, the date field DateField also implements the following:

  • date_object (Date): an accessible representation of the value as a JavaScript object.

Position Field

The position field PositionField does not implement all the basic Field attributes, only bounding_box, polygon and page_id. On top of these, it has access to:

  • rectangle (Mindee::Geometry::Quadrilateral): a Polygon with four points that may be oriented (even beyond canvas).
  • quadrangle (Mindee::Geometry::Quadrilateral): a free polygon made up of four points.

String Field

The text field StringField only has one constraint: it's value is a String (or nil).

Page-Level Fields

Some fields are constrained to the page level, and so will not be retrievable to through the document.


The following fields are extracted for Bank Check V1:

Account Number

account_number (StringField): The check payer's account number.

puts result.document.inference.prediction.account_number.value


amount (AmountField): The amount of the check.

puts result.document.inference.prediction.amount.value

Check Number

check_number (StringField): The issuer's check number.

puts result.document.inference.prediction.check_number.value

Check Position

πŸ“„check_position (PositionField): The position of the check on the document.

for check_position_elem in result.document.check_position do
  puts check_position_elem.polygon

Check Issue Date

date (DateField): The date the check was issued.



payees (Array<StringField>): List of the check's payees (recipients).

for payees_elem in result.document.inference.prediction.payees do
  puts payees_elem.value

Routing Number

routing_number (StringField): The check issuer's routing number.

puts result.document.inference.prediction.routing_number.value

Signature Positions

πŸ“„signatures_positions (Array<PositionField>): List of signature positions

for page in result.document.inference.pages do
  for signatures_positions_elem in page.prediction.signatures_positions do
    puts signatures_positions_elem.polygon.to_s
    puts signatures_positions_elem.quadrangle.to_s
    puts signatures_positions_elem.rectangle.to_s
    puts signatures_positions_elem.boundingBox.to_s


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