This script help to combine a very big image from EasyZoom.

easyzoom_gluer.py

# Image tiler for EasyZoom's image

# This script requires Pillow (https://pillow.readthedocs.io/en/stable/)

# You have to download the .szi file of the EasyZoom image.

# You can find the URL of this file in by "inspecting" the page in the browser
#  and looking at the "Network" tab. Be sure to remove the "?bytes=xxxxxx-yyyyyyy"
#  of the URL params before downloading.

import sys
import re
import io
from functools import cmp_to_key
from PIL import Image

# NOTE: You can use '-' for using stdin/stdout
SRC = sys.argv[1]  # Your .szi file
DST = sys.argv[2]  # The final image path


def eprint(s):
    if DST != '-':
        print(s, file=sys.stderr)


def get_img(jpeg):
    return Image.open(io.BytesIO(jpeg))


szi = (sys.stdin.buffer if SRC == '-' else open(SRC, 'rb')).read()

ZOOM = max(int(x.group(1))
           for x in re.finditer(b'_files/(\d+)/\d+_\d+\.jpgII', szi))

eprint(f'Zoom level: {ZOOM}')

TILES = sorted((
    (int(i.group(1)),
     int(i.group(2)),
     i.group(3))
    for i in re.finditer(b'_files/%i/(\d+)_(\d+)\.jpgII.*?(\xFF\xD8.*?\xFF\xD9)' % ZOOM, szi, re.DOTALL)),
    key=cmp_to_key(lambda t1, t2: t1[0] > t2[0] and t1[1] > t2[1]))

if len(TILES) == 0:
    eprint(f'Zoom level {ZOOM} not found.')
    exit(1)

TILE_W, TILE_H = get_img(TILES[0][2]).size
W, H, LAST_JPEG = TILES[-1]  # Take the last tile's X and Y
LAST_W, LAST_H = get_img(LAST_JPEG).size

img = Image.new('RGB', (TILE_W*W+LAST_W, TILE_H*H+LAST_H))

for x, y, jpeg in TILES:
    eprint(f'{x}x{y}')
    tile_img = get_img(jpeg)
    img.paste(tile_img, (x * TILE_W, y * TILE_H))
    tile_img.close()

if DST == '-':
    DST = sys.stdout

eprint(f'Saving {DST}...')

img.save(DST, "JPEG", optimize=True, quality=100)