gstreamer/gst/spectrum/gstspectrum.c

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/* GStreamer
* Copyright (C) <1999> Erik Walthinsen <omega@cse.ogi.edu>
*
* 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.
*/
#include <string.h>
#include "gstspectrum.h"
static GstElementDetails gst_spectrum_details = {
"Spectrum analyzer",
"Filter/Analysis",
"Run an FFT on the audio signal, output spectrum data",
VERSION,
"Erik Walthinsen <omega@cse.ogi.edu>",
"(C) 1999",
};
/* Spectrum signals and args */
enum {
/* FILL ME */
LAST_SIGNAL
};
enum {
ARG_0,
ARG_WIDTH,
};
static void gst_spectrum_class_init (GstSpectrumClass *klass);
static void gst_spectrum_init (GstSpectrum *spectrum);
static void gst_spectrum_set_property (GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec);
static void gst_spectrum_chain (GstPad *pad, GstBuffer *buf);
#define fixed short
int gst_spectrum_fix_fft(fixed fr[], fixed fi[], int m, int inverse);
void gst_spectrum_fix_loud(fixed loud[], fixed fr[], fixed fi[], int n, int scale_shift);
void gst_spectrum_window(fixed fr[], int n);
static GstElementClass *parent_class = NULL;
/*static guint gst_spectrum_signals[LAST_SIGNAL] = { 0 }; */
GType
gst_spectrum_get_type (void)
{
static GType spectrum_type = 0;
if (!spectrum_type) {
static const GTypeInfo spectrum_info = {
sizeof(GstSpectrumClass), NULL,
NULL,
(GClassInitFunc)gst_spectrum_class_init,
NULL,
NULL,
sizeof(GstSpectrum),
0,
(GInstanceInitFunc)gst_spectrum_init,
};
spectrum_type = g_type_register_static(GST_TYPE_ELEMENT, "GstSpectrum", &spectrum_info, 0);
}
return spectrum_type;
}
static void
gst_spectrum_class_init (GstSpectrumClass *klass)
{
GObjectClass *gobject_class;
gobject_class = (GObjectClass*)klass;
parent_class = g_type_class_ref(GST_TYPE_ELEMENT);
g_object_class_install_property(G_OBJECT_CLASS(klass), ARG_WIDTH,
g_param_spec_int("width","width","width",
G_MININT,G_MAXINT,0,G_PARAM_WRITABLE)); /* CHECKME */
gobject_class->set_property = gst_spectrum_set_property;
}
static void
gst_spectrum_init (GstSpectrum *spectrum)
{
spectrum->sinkpad = gst_pad_new("sink",GST_PAD_SINK);
gst_element_add_pad(GST_ELEMENT(spectrum),spectrum->sinkpad);
gst_pad_set_chain_function(spectrum->sinkpad,gst_spectrum_chain);
spectrum->srcpad = gst_pad_new("src",GST_PAD_SRC);
gst_element_add_pad(GST_ELEMENT(spectrum),spectrum->srcpad);
spectrum->width = 75;
}
static void
gst_spectrum_set_property (GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec)
{
GstSpectrum *spectrum;
/* it's not null if we got it, but it might not be ours */
g_return_if_fail(GST_IS_SPECTRUM(object));
spectrum = GST_SPECTRUM(object);
switch (prop_id) {
case ARG_WIDTH:
spectrum->width = g_value_get_int (value);
break;
default:
break;
}
}
static void
gst_spectrum_chain (GstPad *pad, GstBuffer *buf)
{
GstSpectrum *spectrum;
gint spec_base, spec_len;
gint16 *re, *im, *loud;
gint16 *samples;
gint step,pos,i;
guchar *spect;
GstBuffer *newbuf;
g_return_if_fail(pad != NULL);
g_return_if_fail(GST_IS_PAD(pad));
g_return_if_fail(buf != NULL);
spectrum = GST_SPECTRUM (GST_OBJECT_PARENT (pad));
samples = (gint16 *)GST_BUFFER_DATA(buf);
spec_base = 8;
spec_len = 1024;
im = g_malloc(spec_len * sizeof(gint16));
g_return_if_fail(im != NULL);
loud = g_malloc(spec_len * sizeof(gint16));
g_return_if_fail(loud != NULL);
memset(im,0,spec_len * sizeof(gint16));
/*if (spectrum->meta->channels == 2) { */
re = g_malloc(spec_len * sizeof(gint16));
for (i=0;i<spec_len;i++)
re[i] = (samples[(i*2)] + samples[(i*2)+1]) >> 1;
/*} else */
/* re = samples; */
gst_spectrum_window(re,spec_len);
gst_spectrum_fix_fft(re,im,spec_base,FALSE);
gst_spectrum_fix_loud(loud,re,im,spec_len,0);
if (re != samples) g_free(re);
g_free(im);
step = spec_len / (spectrum->width*2);
spect = (guchar *)g_malloc(spectrum->width);
for (i=0,pos=0;i<spectrum->width;i++,pos += step) {
if (loud[pos] > -60)
spect[i] = (loud[pos] + 60) / 2;
else
spect[i] = 0;
/* if (spect[i] > 15); */
/* spect[i] = 15; */
}
g_free(loud);
gst_buffer_unref(buf);
/* g_free(samples); */
newbuf = gst_buffer_new();
g_return_if_fail(newbuf != NULL);
GST_BUFFER_DATA(newbuf) = spect;
GST_BUFFER_SIZE(newbuf) = spectrum->width;
gst_pad_push(spectrum->srcpad,newbuf);
}
static gboolean
plugin_init (GModule *module, GstPlugin *plugin)
{
GstElementFactory *factory;
/* create an elementfactory for the spectrum element */
factory = gst_element_factory_new ("spectrum",GST_TYPE_SPECTRUM,
&gst_spectrum_details);
g_return_val_if_fail (factory != NULL, FALSE);
gst_plugin_add_feature (plugin, GST_PLUGIN_FEATURE (factory));
return TRUE;
}
GstPluginDesc plugin_desc = {
GST_VERSION_MAJOR,
GST_VERSION_MINOR,
"spectrum",
plugin_init
};