using placeholders where value is empty

I am using the form where in a situation i have to use place holder or title to insert the value in the database, i know we can use

$form.serialize which picks all the values of the form, but in my case value field is always going to be empty and i want to pick placeholders value and title value if placeholder is not defined just like serialization,

is there custom build jquery code or something already build in, how can i can use it just like $(form).serializePlaceholder or $(form).serializetITLE