Looking for Files with Blank Metadata

If you had the free ExifTool installed, you could ask it to show you the filenames of those audio files that are missing some or all of the following information:

exiftool -s -Filename -if '(not $Title or not $Artist or not $AudioSampleRate or not $Album or not $Genre or not $MediaCreateDate)' -ext mp3 -ext m4a *.{mp3,m4a}

Which produces this output:

Because the only .m4a has all of the tested fields filled, and thus fails the condition(s), and two .mp3 have some of the fields missing, and satisfy the test, resulting in output.

If you want to recursively (-r) look through a directory structure and return the full file path to the resulting files:

exiftool -s -Filepath -if '(not $Title or not $Artist or not $AudioSampleRate or not $Album or not $Genre or not $MediaCreateDate)' -r -ext mp3 -ext m4a ~/Music

Try the following in Terminal:

The magic is in the not equal to anything !='*' portion.

mdfind -onlyin ~/Music "kMDItemAlbum !='*'" -name .m4p > results.txt

It returns the full path to each file it finds which I am sure you will find useful. If you run it without the "> results.txt" you can peruse the results in the terminal instead of dumping the results to the results.txt file.

You can read up on the mdfind command by issuing "man mdfind" to view the manual page. You can also issue the "mdimport -X" command to get a schema list of all the metadata kMD attributes.

The assumption is that the candidate audio files are in the current directory that ExifTool is run in, or you must tell it to look in a directory. It is not going to scan your entire Mac for .mp3 or .m4a, nor is it limited to those two extensions. There were two .mp3 and one .m4a on my Desktop when I ran that command there.

Any designated audio file extension that had all, or any, missing metadata item would be reported.

I have no media here that has all of these fields blank, so in order to test alternative ExifTool syntax, I will have to make copies of a few in a separate folder, and then use ExifTool to change these specific fields to have no content. This will take some time…

I have found that ExifTool will not let me add all (some) of your preferred blank tags to my available .mp3 and .m4a media. Any reference to an undefined tag blows up the command. Because of that, any attempt at writing a command-line test for all tags that are blank is costing me more time (>2hrs) than I have available to give to this issue.