101 lines
2.9 KiB
Python
101 lines
2.9 KiB
Python
import io
|
|
from functools import partial, lru_cache
|
|
from itertools import chain, starmap
|
|
from operator import itemgetter, truth
|
|
|
|
import fitz
|
|
from PIL import Image
|
|
from funcy import rcompose, compose, curry, merge
|
|
from tqdm import tqdm
|
|
|
|
from image_prediction.image_extractor.extractor import ImageExtractor, ImageMetadataPair
|
|
from image_prediction.info import Info
|
|
from image_prediction.stitching.stitching import stitch_pairs
|
|
|
|
rounder = rcompose(round, int)
|
|
|
|
|
|
def get_image_metadata(image_info):
|
|
x1, y1, x2, y2 = map(rounder, image_info["bbox"])
|
|
width, height = itemgetter("width", "height")(image_info)
|
|
return {
|
|
Info.WIDTH: width,
|
|
Info.HEIGHT: height,
|
|
Info.X1: x1,
|
|
Info.X2: x2,
|
|
Info.Y1: y1,
|
|
Info.Y2: y2,
|
|
}
|
|
|
|
|
|
def get_page_metadata(page):
|
|
page_width, page_height = map(rounder, page.mediabox_size)
|
|
|
|
return {
|
|
Info.PAGE_WIDTH: page_width,
|
|
Info.PAGE_HEIGHT: page_height,
|
|
Info.PAGE_IDX: page.number,
|
|
}
|
|
|
|
|
|
def extract_pages(doc, page_range):
|
|
page_range = range(page_range.start + 1, page_range.stop + 1)
|
|
pages = map(doc.load_page, page_range)
|
|
return pages
|
|
|
|
|
|
def load_image_from_xref(doc, xref):
|
|
maybe_image = doc.extract_image(xref)
|
|
return Image.open(io.BytesIO(maybe_image["image"])) if maybe_image else None
|
|
|
|
|
|
@lru_cache(maxsize=None)
|
|
def get_image_infos(page: fitz.Page):
|
|
return page.get_image_info(xrefs=True)
|
|
|
|
|
|
def get_images_on_page(doc, page: fitz.Page):
|
|
image_infos = get_image_infos(page)
|
|
xrefs = map(itemgetter("xref"), image_infos)
|
|
images = map(partial(load_image_from_xref, doc), xrefs)
|
|
return images
|
|
|
|
|
|
def get_metadata_for_images_on_page(page: fitz.Page):
|
|
image_infos = get_image_infos(page)
|
|
metadata = map(get_image_metadata, image_infos)
|
|
metadata = map(partial(merge, get_page_metadata(page)), metadata)
|
|
return metadata
|
|
|
|
|
|
class ParsablePDFImageExtractor(ImageExtractor):
|
|
def __init__(self, verbose=False):
|
|
self.doc: fitz.fitz.Document = None
|
|
self.verbose = verbose
|
|
|
|
def __process_images_on_page(self, page: fitz.fitz.Page):
|
|
images = get_images_on_page(self.doc, page)
|
|
metadata = get_metadata_for_images_on_page(page)
|
|
get_image_infos.cache_clear()
|
|
|
|
image_metadata_pairs = starmap(
|
|
ImageMetadataPair, filter(compose(all, curry(map)(truth)), zip(images, metadata))
|
|
)
|
|
image_metadata_pairs = stitch_pairs(list(image_metadata_pairs))
|
|
|
|
return image_metadata_pairs
|
|
|
|
def extract(self, pdf: bytes, page_range: range = None):
|
|
self.doc = fitz.Document(stream=pdf)
|
|
|
|
pages = extract_pages(self.doc, page_range) if page_range else self.doc
|
|
|
|
image_metadata_pairs = chain.from_iterable(
|
|
map(
|
|
self.__process_images_on_page,
|
|
tqdm(pages, desc="Extracting", disable=not self.verbose, total=len(page_range) if page_range else None),
|
|
)
|
|
)
|
|
|
|
return image_metadata_pairs
|