Pytesseract OCR multiple config options

- by mahmood 
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.

References
https://stackoverflow.com/questions/44619077/pytesseract-ocr-multiple-config-options

Pytesseract not working sometimes on perfectly clear Images

- by mahmood 
import cv2
import pytesseract

pytesseract.pytesseract.tesseract_cmd = r"C:\Program Files\Tesseract-OCR\tesseract.exe"

image = cv2.imread('2.jpg',0)
thresh = cv2.threshold(image, 150, 255, cv2.THRESH_BINARY_INV)[1]

result = cv2.GaussianBlur(thresh, (5,5), 0)
result = 255 - result

data = pytesseract.image_to_string(result, lang='eng',config='--psm 6')
print(data)

cv2.imshow('thresh', thresh)
cv2.imshow('result', result)
cv2.waitKey()

We use the --psm 6 config flag since we want to treat the image as a single uniform block of text.

References
https://stackoverflow.com/questions/57719983/pytesseract-not-working-sometimes-on-perfectly-clear-images
https://stackoverflow.com/questions/44619077/pytesseract-ocr-multiple-config-options

Read text in image using pytesseract

- by mahmood 
from PIL import Image
import pytesseract

im = Image.open("sample1.jpg")

text = pytesseract.image_to_string(im, lang = 'eng')

print(text)

Or

import pytesseract
import cv2

pytesseract.pytesseract.tesseract_cmd = 'C:\\Program Files (x86)\\Tesseract-OCR\\tesseract.exe'

image = cv2.imread("ocr.png")
image_grayscal = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY)

data = pytesseract.image_to_string(image_grayscal)

Read texts in white color

import pytesseract
import cv2

pytesseract.pytesseract.tesseract_cmd = 'C:\\Program Files (x86)\\Tesseract-OCR\\tesseract.exe'

image = cv2.imread("ocr.png")
image_grayscal = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY)
inverted_image = cv2.bitwise_not(image_grayscal) # color of text is white so we should invert colors

data = pytesseract.image_to_string(inverted_image)

References
https://stackoverflow.com/questions/50951955/pytesseract-tesseractnotfound-error-tesseract-is-not-installed-or-its-not-i
https://pupli.net/2020/05/inverting-colors-of-image-in-python-with-opencv/

Echo Bot using Python Telegram Bot

- by mahmood 
#!/usr/bin/env python
# -*- coding: utf-8 -*-
# This program is dedicated to the public domain under the CC0 license.

"""
Simple Bot to reply to Telegram messages.
First, a few handler functions are defined. Then, those functions are passed to
the Dispatcher and registered at their respective places.
Then, the bot is started and runs until we press Ctrl-C on the command line.
Usage:
Basic Echobot example, repeats messages.
Press Ctrl-C on the command line or send a signal to the process to stop the
bot.
"""

import logging

from telegram.ext import Updater, CommandHandler, MessageHandler, Filters

# Enable logging
logging.basicConfig(format='%(asctime)s - %(name)s - %(levelname)s - %(message)s',
                    level=logging.INFO)

logger = logging.getLogger(__name__)


# Define a few command handlers. These usually take the two arguments update and
# context. Error handlers also receive the raised TelegramError object in error.
def start(update, context):
    """Send a message when the command /start is issued."""
    update.message.reply_text('Hi!')


def help(update, context):
    """Send a message when the command /help is issued."""
    update.message.reply_text('Help!')


def echo(update, context):
    """Echo the user message."""
    update.message.reply_text(update.message.text)


def error(update, context):
    """Log Errors caused by Updates."""
    logger.warning('Update "%s" caused error "%s"', update, context.error)


def main():
    """Start the bot."""
    # Create the Updater and pass it your bot's token.
    # Make sure to set use_context=True to use the new context based callbacks
    # Post version 12 this will no longer be necessary
    updater = Updater("TOKEN", use_context=True)

    # Get the dispatcher to register handlers
    dp = updater.dispatcher

    # on different commands - answer in Telegram
    dp.add_handler(CommandHandler("start", start))
    dp.add_handler(CommandHandler("help", help))

    # on noncommand i.e message - echo the message on Telegram
    dp.add_handler(MessageHandler(Filters.text, echo))

    # log all errors
    dp.add_error_handler(error)

    # Start the Bot
    updater.start_polling()

    # Run the bot until you press Ctrl-C or the process receives SIGINT,
    # SIGTERM or SIGABRT. This should be used most of the time, since
    # start_polling() is non-blocking and will stop the bot gracefully.
    updater.idle()


if __name__ == '__main__':
    main()

References
https://github.com/python-telegram-bot/python-telegram-bot/blob/master/examples/echobot2.py