To determine how many eighth notes are in an audio sample, you need to know the tempo (beats per minute) and the duration of the sample.
If the sample has a specific length and a known tempo, you can calculate the number of beats and then determine how many eighth notes that amounts to. Generally, one quarter note equals two eighth notes.
If you provide the tempo and duration of the sample, I can help you calculate the number of eighth notes. Otherwise, based on the options you provided (048 or 16), I cannot definitively say which is correct without more context.