demo_v2.py

import os
import cv2
import numpy as np
from pdf2image import convert_from_path

from main import RapidOCR
ocr_engine = RapidOCR()

dataPath = '/home/tung/Tung_Works/OCR_code/OCR-20250423T073748Z-001/OCR/OCR辨識失敗-部分樣本'

from image_enhancement import enhance_image

list_pdf = []
for root, dirs, files in os.walk(dataPath):
    for file in files:
        if file.endswith('.pdf'):
            pdf_f = os.path.join(root, file)
            assert os.path.exists(pdf_f)
            list_pdf.append(pdf_f)
sorted(list_pdf)

def adaptive_threshold_to_rgb(image_rgb):
    """
    Apply adaptive thresholding on the L channel of LAB color space 
    and reconstruct the thresholded image as RGB.

    Parameters:
        image_rgb (numpy.ndarray): Input RGB image.

    Returns:
        thresholded_rgb (numpy.ndarray): RGB image after thresholding the L channel.
    """
    # Convert RGB to LAB color space
    image_lab = cv2.cvtColor(image_rgb, cv2.COLOR_RGB2LAB)

    # Split LAB channels
    l_channel, a_channel, b_channel = cv2.split(image_lab)

    # Apply adaptive thresholding to the L channel
    thresholded_l = cv2.adaptiveThreshold(
        l_channel, 
        maxValue=255, 
        adaptiveMethod=cv2.ADAPTIVE_THRESH_GAUSSIAN_C,  # or ADAPTIVE_THRESH_MEAN_C
        thresholdType=cv2.THRESH_BINARY, 
        blockSize=11, 
        C=2
    )

    # Merge thresholded L channel back with original A and B channels
    updated_lab = cv2.merge((thresholded_l, a_channel, b_channel))

    # Convert LAB back to RGB
    thresholded_rgb = cv2.cvtColor(updated_lab, cv2.COLOR_LAB2RGB)

    return thresholded_rgb

for idx, pdf_f in enumerate(list_pdf):
    bs_name = os.path.basename(pdf_f)
    bs_name_0 = os.path.splitext(bs_name)[0]

#    images = convert_from_path(pdf_f, dpi=900)
    images = convert_from_path(pdf_f, dpi=300, first_page=1, last_page=3)
    for i, image in enumerate(images):
        img = np.array(image)
        print(img.shape)
        parameters = {}
        parameters['local_contrast'] = 1.2  # 1.2x increase in details
        parameters['mid_tones'] = 0.5  # middle of range
        parameters['tonal_width'] = 0.5  # middle of range
        parameters['areas_dark'] = 0.7  # 70% improvement in dark areas
        parameters['areas_bright'] = 0.5  # 50% improvement in bright areas
        parameters['brightness'] = 0.1  # slight increase in overall brightness
        parameters['saturation_degree'] = 1.2  # 1.2x increase in color saturation
        parameters['preserve_tones'] = True
        parameters['color_correction'] = True
        img = enhance_image(img, parameters, verbose=False)  
        #print(img.shape, img.dtype, img.max(), img.min())
        img = np.uint8(img*255.)

        enhanced_img_bgr = cv2.cvtColor(img, cv2.COLOR_RGB2BGR)  # Save in OpenCV-compatible format
        cv2.imwrite(f'{bs_name_0}_{i + 1}.jpg', enhanced_img_bgr)
        print(bs_name_0, i )
        rotation_attempts = 0  # Track rotation count
        
        while rotation_attempts < 4:  # Rotate at most 4 times (90°, 180°, 270°, and back to original orientation)
            result, _ = ocr_engine(img, use_det=True, use_cls=False, use_rec=True)
            detected = False  # Flag to check detection status
            if result:
                test_list = [r[1] for r in result]
                #print(test_list[-5:])

                for j in range(len(test_list) - 1):  # Loop up to the second-to-last row
                    count1 = test_list[j].count("<")
                    count2 = test_list[j + 1].count("<")
                    if count1 > 1 and count2 > 1:
                        print(bs_name_0)                                                                                                                                   
                        print(f"Consecutive rows with '<' more than 2 times each:")
                        print(f"Row 1: {test_list[j]} (Occurrences: {count1})")
                        print(f"Row 2: {test_list[j + 1]} (Occurrences: {count2})")
                        detected = True
                        break
                
                if detected:
                    break  # Stop further rotation since rows are detected
                
            # Rotate the image by 90 degrees
            img = cv2.rotate(img, cv2.ROTATE_90_CLOCKWISE)
            rotation_attempts += 1
        
        if not detected:
            img = adaptive_threshold_to_rgb(img)
            rotation_attempts = 0  # Track rotation count
            
            while rotation_attempts < 4:  # Rotate at most 4 times (90°, 180°, 270°, and back to original orientation)
                result, _ = ocr_engine(img, use_det=True, use_cls=False, use_rec=True)
                detected = False  # Flag to check detection status
                if result:
                    test_list = [r[1] for r in result]
                    #print(test_list[-5:])

                    for j in range(len(test_list) - 1):  # Loop up to the second-to-last row
                        count1 = test_list[j].count("<")
                        count2 = test_list[j + 1].count("<")
                        if count1 > 1 and count2 > 1:
                            print(bs_name_0)
                            print(f"Consecutive rows with '<' more than 2 times each:")
                            print(f"Row 1: {test_list[j]} (Occurrences: {count1})")
                            print(f"Row 2: {test_list[j + 1]} (Occurrences: {count2})")
                            detected = True
                            break
                    
                    if detected:
                        break  # Stop further rotation since rows are detected
                    
                # Rotate the image by 90 degrees
                img = cv2.rotate(img, cv2.ROTATE_90_CLOCKWISE)
                rotation_attempts += 1