1 """

     2     Rendering images as thumbnails/previews.

     3 """

     4 

     5 import PIL.Image

     6 

     7 class RenderMachine (object) :

     8     """

     9         RAWR! I'm the render machine!

    10 

    11         TODO: use multithreaded rendering (PIL supports it)

    12     """

    13 

    14     def __init__ (self, config) :

    15         """

    16             Use the given Configuration object's settings for rendering

    17         """

    18 

    19         self.config = config

    20 

    21     def render_out (self, image, size, file) :

    22         """

    23             Creates a thumbnail from the given Image of the given `size`, and saves it at `out`.

    24 

    25             Returns the file for convenience

    26         """

    27 

    28         # load the PIL.Image

    29         img = image.image

    30 

    31         # we need to create a copy, as .thumbnail mutates the Image

    32         img_out = img.copy()

    33 

    34         # then resample to given size

    35         img_out.thumbnail(size, resample=True)

    36 

    37         # and write out

    38         img_out.save(file.path)

    39 

    40         return file

    41    

    42     def render_lazy (self, image, size, out) :

    43         """

    44             Renders the given image with render_out if `out` does not yet exist or is older than image.

    45         """

    46 

    47         # stat the output file

    48         out_stat = out.stat(soft=True)

    49 

    50         # compare

    51         if not out_stat or out_stat.st_mtime < image.stat.st_mtime :

    52             # render anew

    53             return self.render_out(image, size, out)

    54 

    55         else :

    56             # already rendered

    57             return out