Problem
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* Currently, Thumbnailator does not have good support for large image files.

For example, there is no protection against running out of memory, and this 
behavior is completely dependent upon the JVM's memory settings.


Solution
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* Support tiled reading of image files, rather than reading the entire files at 
once, as is implemented currently.


Complications
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* Changes to support reading images by tiles will most likely lead to changes 
to the API.