Detect only horizontal text with Tesseract

Question

I've an image with some horizontal and vertical text. And I'm detecting text using tesseract OCR. And here is the array tesseract returns

'text': ['', '', '', '', 'Some', 'other', 'text', 'horizontal', '', '', '', 'JEDIY9A', ']xO]', 'WOPUeI', 'BWOS', 'SI', 'SIUL']

As you can see it only detect horizontal text correctly. So is there a way to force tesseract to detect only horizontal text? So later I will rotate the image by 90 and again pass image to detect vertical text(which is now horizontal).

Or is there a simple solution?

Answer 1

Read about the page segmentation you will it there . there is one valid value of psm that does exactly what you want....

Page segmentation modes:
  0    Orientation and script detection (OSD) only.
  1    Automatic page segmentation with OSD.
  2    Automatic page segmentation, but no OSD, or OCR.
  3    Fully automatic page segmentation, but no OSD. (Default)
  4    Assume a single column of text of variable sizes.
  5    Assume a single uniform block of vertically aligned text.
  6    Assume a single uniform block of text.
  7    Treat the image as a single text line.
  8    Treat the image as a single word.
  9    Treat the image as a single word in a circle.
 10    Treat the image as a single character.
 11    Sparse text. Find as much text as possible in no particular order.
 12    Sparse text with OSD.
 13    Raw line. Treat the image as a single text line,
                        bypassing hacks that are Tesseract-specific.

try --psm 6 or 12

or you can try this answer here is a solution that could work for you How do I detect vertical text with OpenCV for extraction

Answer 2

pytesseract is not rotation-invariant. Therefore you need to do additional preprocessing to read the vertical text.

For instance: rotating text 90 degreee clock-wise.

img = cv2.rotate(img, cv2.ROTATE_90_CLOCKWISE)

When you read

print(pytesseract.image_to_string(gry).split("\n")[0])

Result:

This is some random text vertical

So how can you read the both text at the same time?

• First read the horizontal text

  • import cv2
    import pytesseract
    
    img = cv2.imread("7IIrb.jpg")
    gry = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)
    txt = pytesseract.image_to_string(gry).split("\n")[0]
    print(txt)
    

  • Then rorate the image 90 degree clock-wise

    • gry = cv2.rotate(gry, cv2.ROTATE_90_CLOCKWISE)
      txt = pytesseract.image_to_string(gry).split("\n")[0]
      print(txt)
      

  • Result:

    Some other text horizontal
    This is some random text vertical
    

Code:

---

import cv2
import pytesseract

img = cv2.imread("7IIrb.jpg")
gry = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)
txt = pytesseract.image_to_string(gry).split("\n")[0]
print(txt)
gry = cv2.rotate(gry, cv2.ROTATE_90_CLOCKWISE)
txt = pytesseract.image_to_string(gry).split("\n")[0]
print(txt)