I have a directory containing about 7,000 music files.  I used lame to recursively re-encode all files in it to a separate directory, outputting all files with the same relative path and file name.  The output files have a .mp3 extension, but some of the input files had different extensions (.wma, .aac, etc).I can see that there is a file count difference of ~100 files missing in the output directory.  What I want to do is run a compare of the two directories and obtain a list of the files that exist in the source, but not in the destination.  This would be simple enough except I need to ignore differences in file extension.I've tried using rsync with dry-run turned on but I couldn't figure out a way to ignore file extensions.  I've also tried diff but was unable to find an option to only check by name but ignore file extensions.  I started thinking I could just do a recursive ls on both directories, remove the file extensions, and then compare the outputs, but I really have no idea on where to start with modifying the ls output using sed or awk since I'm a compete noob with those.
Recursively compare directory contents by name, ignoring file extensions
directory;shell script;diff;filenames