ruby on rails - How to detect extension of image without extension? -

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my situation: have application, based on rubyonrails. use carrierwave images uploading.

i have many files saved without extensions mistakenly. so, of these have content_type empty value

is there way restore extensions these images?

thanks

you might have infer file signatures: http://en.wikipedia.org/wiki/list_of_file_signatures


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