Description:
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For JPEG images created from a file getCompressionQuality() returns 0. (It returns a correct value following a call to setCompressionQuality).
Now I may be naive here and perhaps it is not possible to get that value once the image is compressed - in which case just close this bug.

Reproduce code:
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$image = new Imagick($jpg_file_name);
echo $image->getCompressionQuality();

Expected result:
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Some value for compression Quality

Actual result:
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0