mpeg3
Note: This is taken from the Chicken Wiki, where a more recent version could be available.
The MPEG3 is a thin wrapper around the libmpeg3 C library.
The official documentation for the C library is available here:
(use mpeg3 format-modular)
(define *path* "/tmp/file.mp3")
; Verify that the file has the right signature:
(unless (mpeg3-check-sig *path*)
(error "Invalid file type"))
; Open the file:
(define *file* (mpeg3-open *path*))
; Make sure the file has audio:
(unless (mpeg3-has-audio *file*)
(error "File doesn't have audio"))
; Get the total number of audio streams in the file:
(define *total-streams* (mpeg3-total-astreams *file*))
; Print information for each audio stream in the file:
(let loop ((stream 0))
(unless (= stream *total-streams*)
(format #t "Stream: ~A~% Channels: ~A~% Sample rate: ~A~% Samples: ~A~%"
stream
(mpeg3-audio-channels *file* stream)
(mpeg3-sample-rate *file* stream)
(mpeg3-audio-samples *file* stream))
(loop (+ stream 1))))
; Close the file. This step is optional: if you don't do it, Chicken
; will close it when it no longer is required. However, if you open
; a lot of files you will want to close them as soon as you know you'll
; no longer require them.
(mpeg3-close *file*)
The mpeg3 egg was created by Alejandro Forero Cuervo.
Copyright © 2006 Alejandro Forero Cuervo <azul@freaks-unidos.net>
The mpeg3 egg is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.
The mpeg3 egg is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with the mpeg3 egg; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.