OCR Utils

Quick Start

To get started:

• Select an operation from the Choose Operation dropdown
• Send OCR bounding boxes and the target word/phrase via msg.payload
• Receive matching results in msg.payload

Configuration

Configuration varies by operation type.

Common Input Format

msg.payload.word_to_search (string | array)

Word or phrase (or a list of words/phrases) to search for.

msg.payload.list_of_bboxes (array)

OCR corpus bounding boxes. This must be a list in one of these common formats:

• Word-level: [[[x1, y1, x2, y2], "text"], ...]
• Phrase-level: [[[x1, y1, x2, y2], [[[x1, y1, x2, y2], "text"], ...], "phrase text"], ...]

msg.payload.region_bounding_boxes (array, optional)

Restrict matching to one or more regions.

Format: [[x1, y1, x2, y2], ...]

Output by Operation

msg.payload contains an output field with the results.

Return Matches (matching)

msg.payload.output is a dictionary keyed by the searched word/phrase.

Validate Word (validate_word)

msg.payload.output is an object with a matches field.

Available Operations

This block currently supports:

• Return Matches (matching)
• Validate Word (validate_word)

Example

Input (msg.payload)

{
  "word_to_search": "Invoice",
  "list_of_bboxes": [[[10, 20, 50, 40], "Invoice"], [[60, 70, 100, 90], "Total"]]
}

Output (msg.payload)

{
  "output": {
    "Invoice": [
      { "word": "Invoice", "word_bbox": [10, 20, 50, 40], "confidence": 100.0, "edit_distance": 0 }
    ]
  }
}

Errors

When the block fails, it raises an error. Use a Catch block in your flow to handle failures and inspect the error payload.

Common mistakes

• Invalid OCR format: Input data doesn't match expected OCR format.
• Missing required fields: word_to_search and list_of_bboxes are required.
• Service unavailable: The service is unavailable or unreachable.

Best Practices

• Use OCR Utils after OCR block to post-process results
• Group words into lines for better readability
• Filter low-confidence results to improve quality
• Sort results by position for logical text flow