gtk_pixbuf_scale_simple () can kill a machine with 512MiB of RAM (like mine) using a 1024x768 PNG and resizing it to 1x1. A 1152x864 PNG will kill a 1GiB machine too.

Test case:

/* gcc -o gdk-pixbuf-scale $(pkg-config --cflags --libs gtk+-2.0) gdk-pixbuf-scale.c */
#include <stdlib.h>
#include <gtk/gtk.h>
#include <gdk-pixbuf/gdk-pixbuf.h>

int main ()
{
        GtkWidget *image;
        GdkPixbuf *pixbuf;

        gtk_init (NULL, NULL);

        image = gtk_image_new_from_file ("800x600image.png");
        g_assert (image != NULL);

        pixbuf = gtk_image_get_pixbuf (GTK_IMAGE (image));
        g_assert (pixbuf != NULL);

        gdk_pixbuf_scale_simple (pixbuf, 1, 1, GDK_INTERP_BILINEAR);

        return EXIT_SUCCESS;
}