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Here is the output of thumbnail generation for the file the script failed on.  Presumably it throws that error when `checking image resolution.`

Debugging is on (1596539215)

Request options:

Array

(

[skipNotification] => 1

[caching] =>

[debug] => 1

)

In use options:

Array

(

[skipNotification] => 1

[caching] =>

[debug] => 1

[width] => 400

[height] => 400

[geometry] => contain

[pageNo] => 0

[forceExt] => png

)

Processing: /filerun/IMG_34667.png

As: png

File size: 81025 bytes (79 KB)

File is safe for web.

File is smaller than 8 MB.

Checking image resolution.