gstreamer/gst/spectrum/demo-osssrc.c

#include <gnome.h>
#include <gst/gst.h>

extern gboolean _gst_plugin_spew;

void spectrum_chain(GstPad *pad,GstBuffer *buf);
gboolean idle_func(gpointer data);

GtkWidget *drawingarea;

int main(int argc,char *argv[]) {
  GstElement *bin;
  GstElementFactory *srcfactory;
  GstElement *src;
  GstElementFactory *spectrumfactory;
  GstElement *spectrum;
  GstPad *spectrumpad;

  GtkWidget *appwindow;

  _gst_plugin_spew = TRUE;

  gst_init(&argc,&argv);
  gnome_init("Spectrum","0.0.1",argc,argv);

  bin = gst_bin_new("bin");

  srcfactory = gst_elementfactory_find("osssrc");
  spectrumfactory = gst_elementfactory_find("gstspectrum");

  src = gst_elementfactory_create(srcfactory,"src");
  gtk_object_set(GTK_OBJECT(src),"bytes_per_read",(gulong)1024,NULL);
  spectrum = gst_elementfactory_create(spectrumfactory,"spectrum");
  gtk_object_set(GTK_OBJECT(spectrum),"width",256,NULL);


  gst_bin_add(GST_BIN(bin),GST_ELEMENT(src));
  gst_bin_add(GST_BIN(bin),GST_ELEMENT(spectrum));

  gst_pad_connect(gst_element_get_pad(src,"src"),
                  gst_element_get_pad(spectrum,"sink"));

  spectrumpad = gst_pad_new("sink",GST_PAD_SINK);
  gst_pad_set_chain_function(spectrumpad,spectrum_chain);

  gst_pad_connect(gst_element_get_pad(spectrum,"src"),spectrumpad);

  appwindow = gnome_app_new("spectrum","Spectrum");
  drawingarea = gtk_drawing_area_new();
  gtk_drawing_area_size(GTK_DRAWING_AREA(drawingarea),256,32);
  gnome_app_set_contents(GNOME_APP(appwindow),drawingarea);
  gtk_widget_show_all(appwindow);

  gst_element_set_state(GST_ELEMENT(bin),GST_STATE_READY);
  gst_element_set_state(GST_ELEMENT(bin),GST_STATE_PLAYING);

  g_idle_add(idle_func,src);

  gtk_main();

  return 0;
}


void spectrum_chain(GstPad *pad,GstBuffer *buf) {
  gint i;
  guchar *data = buf->data;

  gdk_draw_rectangle(drawingarea->window,drawingarea->style->black_gc,
                     TRUE,0,0,GST_BUFFER_SIZE(buf),25);
  for (i=0;i<GST_BUFFER_SIZE(buf);i++) {
    gdk_draw_rectangle(drawingarea->window,drawingarea->style->white_gc,
                       TRUE,i,32-data[i],1,data[i]);
  }
  gst_buffer_unref(buf);
}

gboolean idle_func(gpointer data) {
  //gst_src_push(GST_SRC(data));
  return TRUE;
}