How to extract not original images but cropped images

[yuki-tashiro]

Hello,

Thank you for your great work on this project!

I would like to know how I can extract the cropped portion of images in a PDF, instead of the original, uncropped images.

Currently, I'm able to extract the original images using page.get_image_bbox(), but this doesn't account for images that are cropped on the page. What I need is to extract only the part of the image that is visible on the PDF page, excluding the portions that may have been cropped out.

Here’s my code along with the input PDF and the output images:

import fitz  # PyMuPDF
from PIL import Image
import io

def extract_visible_images_from_pdf(pdf_path, output_folder):

    pdf_document = fitz.open(pdf_path)

    # Process each page
    for page_num in range(len(pdf_document)):
        page = pdf_document.load_page(page_num)
        
        # Render the entire page as an image
        pix = page.get_pixmap()
        page_image = Image.frombytes("RGB", [pix.width, pix.height], pix.samples)

        image_list = page.get_images(full=True)
        print(f"image_list: {image_list}")

        # Get all images on the page
        if image_list:
            for img_index, img_info in enumerate(image_list):
                xref = img_info[0]
                base_image = pdf_document.extract_image(xref)
                image_stream = io.BytesIO(base_image["image"])
                img = Image.open(image_stream)

                # Extract the image bytes from the PDF
                image_rect = page.get_image_bbox(img_info)
                visible_image = page_image.crop((
                    int(image_rect.x0),
                    int(image_rect.y0),
                    int(image_rect.x1),
                    int(image_rect.y1)
                ))

                img_output_path = f"{output_folder}/page_{page_num + 1}_image_{img_index + 1}.png"
                
                visible_image.save(img_output_path)
                print(f"Saved cropped image: {img_output_path}")
        else:
            print(f"No images found on page {page_num + 1}")

    pdf_document.close()

# pdf_path = "/content/drive/MyDrive/MatsuoLab/LLaVA-Med-JP/tp240424-01d_02.pdf"
pdf_path = "/content/input.pdf"
output_folder = "/content/"
extract_visible_images_from_pdf(pdf_path, output_folder)

Here is my original pdf.

• input.pdf

Extrated images

• 
• 

Ideal extracted images

• 

Could you please guide me on how to modify the code to achieve this?

Thank you for your assistance!

[JorjMcKie]

This is no issue, but a typical Discussions item ... transferring.

[yuki-tashiro]

Thank you for transferring to the correct place.

[JorjMcKie]

This is not easy to achieve, because there is no definition of what "cropped" means.
Like in your example: you did not crop anything - you just covered some of the image parts. There is no way of determining which parts have remained visible.
If you however know the window of visibility, the obviously most canonic way is to make a pixmap of that region and save it.