Implement progress bars for DZI creation

They are off by default. To show them, call: `create(..., quiet=False)`

Implements openzoom#6

deepzoom/__init__.py

@@ -36,6 +36,7 @@
 #
 
 import io
+import itertools
 import math
 import optparse
 import os
@@ -48,6 +49,7 @@
 import xml.dom.minidom
 
 import PIL.Image
+from tqdm import tqdm, trange
 
 from collections import deque
 
@@ -401,14 +403,16 @@ def get_image(self, level):
             return self.image.resize((width, height), PIL.Image.ANTIALIAS)
         return self.image.resize((width, height), RESIZE_FILTERS[self.resize_filter])
 
-    def tiles(self, level):
+    def tiles(self, level, quiet=True):
         """Iterator for all tiles in the given level. Returns (column, row) of a tile."""
         columns, rows = self.descriptor.get_num_tiles(level)
-        for column in range(columns):
-            for row in range(rows):
-                yield (column, row)
+        quiet = quiet or (columns * rows < 500)
+        yield from tqdm(
+            itertools.product(range(columns), range(rows)),
+            unit="tile", total=columns*rows, leave=None, disable=quiet
+        )
 
-    def create(self, source, destination):
+    def create(self, source, destination, quiet=True):
         """Creates Deep Zoom image from source file and saves it to destination."""
         self.image = PIL.Image.open(safe_open(source))
         width, height = self.image.size
@@ -421,10 +425,13 @@ def create(self, source, destination):
         )
         # Create tiles
         image_files = _get_or_create_path(_get_files_path(destination))
-        for level in range(self.descriptor.num_levels):
+        for level in trange(
+            self.descriptor.num_levels,
+            desc="Creating DZI", unit="level", disable=quiet
+        ):
             level_dir = _get_or_create_path(os.path.join(image_files, str(level)))
             level_image = self.get_image(level)
-            for (column, row) in self.tiles(level):
+            for (column, row) in self.tiles(level, quiet=quiet):
                 bounds = self.descriptor.get_tile_bounds(level, column, row)
                 tile = level_image.crop(bounds)
                 format = self.descriptor.tile_format

setup.py

@@ -13,7 +13,7 @@
     keywords="deepzoom seadragon dzi dzc seadragonajax seadragonmobile silverlightdeepzoom microsoft openzoom",
     packages=find_packages(),
     license="BSD 3-Clause License",
-    install_requires=["Pillow>=6"],
+    install_requires=["Pillow>=6", "tqdm"],
     url="https://github.com/openzoom/deepzoom.py",
     include_package_data=True,
     classifiers=[