Could give me a simple complete sample about drawing Pixel in Gnome..plz

["金" <unto pchome com tw>]

Hello ,
I am new to study the GTK 2.0 and I have a book of "Beginning.Linux.Programming.3rdEd" 
But it isn't mention about image processing.So I go to www.gtk.org  web site ,tutorial document  also no 
mention.
I find some example ,that can show "image file" , below is my subfunction to show image.
I also read something about "pixel buffer function" at GTK relative web site,but it's not structure ,don't 
have example.
I don't know how to use that.
so...Could give me simple complete program,about how to show  pixel in screen(if I have pixel array,and RGB 
palette array) .
Thanks a lots.

Regards.
Unto 

**********************************************************************
void showimage(char *windowsTitle,char *file)
{
GtkWidget *subwindow;
GtkWidget *image; 

  subwindow = gtk_window_new (GTK_WINDOW_TOPLEVEL);
  gtk_window_set_title (GTK_WINDOW(subwindow), windowsTitle);
  gtk_window_set_position(GTK_WINDOW(subwindow),GTK_WIN_POS_CENTER);     

g_signal_connect (G_OBJECT (subwindow), "destroy",
                    G_CALLBACK (gtk_main_quit),
                    NULL);

 image = gtk_image_new_from_file (file);
 gtk_container_add (GTK_CONTAINER (subwindow), image);

 gtk_widget_show_all (subwindow);
 gtk_main ();
}//show image end.