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#Pdf image extractor python pdf#
#Pdf image extractor python install#
#Pdf image extractor python update#

# get coordinates (y,x) - alternately see below for (x,y) Gray = cv2.cvtColor(img,cv2.COLOR_BGR2GRAY)

#Pdf image extractor python pdf#

# you could do the same for imBox and page.cropBoxĮxtract x y coordinates from image in pdf pythonĮxtract x,y coordinates of each pixel from an image in Python argv, sys.Previous Post Next Post Extract x y coordinates from image in pdf python

# recreate the PDF file with the new_sign

#Pdf image extractor python update#

# Process the metadata and update with new image's details # Include the \n to ensure extact match and avoid partials from 111, 211… You can use the following Python script to achieve that. Now the job is to switch the object 11’s image data with our image’s data. Step 5 – Replacing the image with another image Now we can identify the object identifier, in this case it is 11 0 obj. I opened the uncompressed.pdf in VIM and searched for the most unique value I have found for the image – its size. Step 4 – Identifying the object in PDF that represents the image There are two images which matches the height and width, thankfully they have different file sizes.

Now open your images check their file’s height, width and file size and mark the details for the one to replace. That extracts the files and names them after the prefix we provided like this image-000.jpg image-001.jpg image-002.jpg. Next extract all the images in their original formats using This will list all the images in the PDF with their metadata.

#Pdf image extractor python install#

To do that install pdfimages command-line tool (part of poppler-utils) and run pdfimages -list uncompressed.pdf. We will have to first extract the images from the PDF and match the PDF object to the image using its metadata like height and width. PDF is essentially a collection of objects and a PDF file might contain multiple images, there is no way to identify a particular image in the binary data of the PDF file (unless you are from Matrix). Step 3 – Identifying the image to replace Let us open the uncompressed.pdf in VIM to see the difference. What this command does is, it uncompresses the file and makes it easier to read and manipulate. Pdftk sample.pdf output uncompressed.pdf uncompress Use a PDF manipulation called toolkit called PDFtk. Step 2 – Uncompressing the PDF and extracting the images Image binary data here like to successfully replace an image we will have to replace the image binary data and the metadata like width and height. A image in our case would be represented as There is usually an identifier like int int obj followed by some metadata and then a stream of binary information starting with stream and ends with endstream and endobj.

Without getting into the entirety of the PDF spec, let us see what this means.

So opening a PDF file in a text editor like VIM will show something like this. Humans invented the PDF format, which means they used words to describe things in the file, which means we can read them. With that learnt, I set out to achieve the goal anyway.

The issue is when you want to delete something and replace it with something else.

Almost all positive changes like adding text or image and whole page changes like rotating, cropping are usually possible and so are all read operations like text, image extraction. There is no logical way it is done that make general purposes tools manipulate the PDF in a consistent way.

PDF is a dump of instructions to put things in specific places.

While there are a number of tools to deal with PDF in Python, the general purpose tools can only do so much because… reason 2.

I recently worked on a project involving replacing images in a PDF which taught me a couple of things. Being a freelancer is an interesting role.