/* -*- c-basic-offset: 2 -*- * * GStreamer * Copyright (C) 1999-2001 Erik Walthinsen <omega@cse.ogi.edu> * 2006 Dreamlab Technologies Ltd. <mathis.hofer@dreamlab.net> * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Library General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library 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 * Library General Public License for more details. * * You should have received a copy of the GNU Library General Public * License along with this library; if not, write to the * Free Software Foundation, Inc., 59 Temple Place - Suite 330, * Boston, MA 02111-1307, USA. * * * this windowed sinc filter is taken from the freely downloadable DSP book, * "The Scientist and Engineer's Guide to Digital Signal Processing", * chapter 16 * available at http://www.dspguide.com/ * */ #ifndef __GST_BPWSINC_H__ #define __GST_BPWSINC_H__ #include "gstfilter.h" #include <gst/gst.h> #include <gst/audio/gstaudiofilter.h> G_BEGIN_DECLS #define GST_TYPE_BPWSINC \ (gst_bpwsinc_get_type()) #define GST_BPWSINC(obj) \ (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_BPWSINC,GstBPWSinc)) #define GST_BPWSINC_CLASS(klass) \ (G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_BPWSINC,GstBPWSincClass)) #define GST_IS_BPWSINC(obj) \ (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_BPWSINC)) #define GST_IS_BPWSINC_CLASS(klass) \ (G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_BPWSINC)) typedef struct _GstBPWSinc GstBPWSinc; typedef struct _GstBPWSincClass GstBPWSincClass; typedef void (*GstBPWSincProcessFunc) (GstBPWSinc *, guint8 *, guint8 *, guint); /** * GstBPWSinc: * * Opaque data structure. */ struct _GstBPWSinc { GstAudioFilter element; /* < private > */ GstBPWSincProcessFunc process; gint mode; gint window; gfloat lower_frequency, upper_frequency; gint kernel_length; /* length of the filter kernel */ gdouble *residue; /* buffer for left-over samples from previous buffer */ gdouble *kernel; gboolean have_kernel; gint residue_length; guint64 latency; GstClockTime next_ts; guint64 next_off; }; struct _GstBPWSincClass { GstAudioFilterClass parent_class; }; GType gst_bpwsinc_get_type (void); G_END_DECLS #endif /* __GST_BPWSINC_H__ */