General :: Rename Multiple Files In Multiple Directories/subdirectories Recursively?

I am to rename all the files within a directory (which contains multiple subdirectories) recursively without invalid characters.

I tried the coding posted above.

find . -type f -printf '%p
' | while read file; do
oldfile=$(basename "$file")
newfile=$(echo "$oldfile" | sed 's/[^A-Za-z0-9_.]/_/g')
if [ ! "$newfile" == "$oldfile" ]; then
echo mv "$file" "${file%$oldfile}$newfile"
code....

but I get an error on both of them stating "find: bad option -printf find: [-H | -L] path-list predicate-list"