Merge pull request #344 from kradalby/write-jpeg-memory-leak

Force cleanup of objects in write_jpeg (fix memory leak)

osxphotos/imageconverter.py

@@ -6,6 +6,7 @@
 
 import pathlib
 
+import objc
 import Metal
 import Quartz
 from Cocoa import NSURL
@@ -20,6 +21,7 @@ class ImageConversionError(Exception):
 
     pass
 
+
 class ImageConverter:
     """ Convert images to jpeg.  This class is a singleton
         which will re-use the Core Image CIContext to avoid
@@ -67,6 +69,12 @@ class ImageConverter:
             ImageConversionError if error during conversion
         """
 
+        # Set up a dedicated objc autorelease pool for this function call.
+        # This is to ensure that all the NSObjects are cleaned up after each
+        # call to prevent memory leaks.
+        # https://developer.apple.com/library/archive/documentation/Cocoa/Conceptual/MemoryMgmt/Articles/mmAutoreleasePools.html
+        # https://pyobjc.readthedocs.io/en/latest/api/module-objc.html#memory-management
+        with objc.autorelease_pool():
             # accept input_path or output_path as pathlib.Path
             if not isinstance(input_path, str):
                 input_path = str(input_path)
@@ -103,7 +111,10 @@ class ImageConverter:
             output_options = NSDictionary.dictionaryWithDictionary_(
                 {"kCGImageDestinationLossyCompressionQuality": compression_quality}
             )
-        _, error = self.context.writeJPEGRepresentationOfImage_toURL_colorSpace_options_error_(
+            (
+                _,
+                error,
+            ) = self.context.writeJPEGRepresentationOfImage_toURL_colorSpace_options_error_(
                 input_image, output_url, output_colorspace, output_options, None
             )
             if not error: