'''
PassportEye::Util: PDF processing utilities.
Author: Konstantin Tretyakov
License: MIT
'''
import sys
from pdfminer.pdfparser import PDFParser
from pdfminer.pdfdocument import PDFDocument
from pdfminer.pdfpage import PDFPage
from pdfminer.pdfinterp import PDFResourceManager
from pdfminer.pdfinterp import PDFPageInterpreter
from pdfminer.converter import PDFPageAggregator
from pdfminer.layout import LTFigure, LTImage
def extract_first_jpeg_in_pdf(fstream):
"""
Reads a given PDF file and scans for the first valid embedded JPEG image.
Returns either None (if none found) or a string of data for the image.
There is no 100% guarantee for this code, yet it seems to work fine with most
scanner-produced images around.
More testing might be needed though.
Note that in principle there is no serious problem extracting PNGs or other image types from PDFs,
however at the moment I do not have enough test data to try this, and the one I have seems to be unsuitable
for PDFMiner.
:param fstream: Readable binary stream of the PDF
:return: binary stream, containing the whole contents of the JPEG image or None if extraction failed.
"""
parser = PDFParser(fstream)
document = PDFDocument(parser)
rsrcmgr = PDFResourceManager()
device = PDFPageAggregator(rsrcmgr)
interpreter = PDFPageInterpreter(rsrcmgr, device)
pages = PDFPage.create_pages(document)
for page in pages:
interpreter.process_page(page)
layout = device.result
for el in layout:
if isinstance(el, LTFigure):
for im in el:
if isinstance(im, LTImage):
# Found one!
st = None
try:
imdata = im.stream.get_data()
except:
# Failed to decode (seems to happen nearly always - there's probably a bug in PDFMiner), oh well...
imdata = im.stream.get_rawdata()
if imdata is not None and imdata.startswith(b'\xff\xd8\xff\xe0'):
return imdata
return None
