func Main(gc draw2d.GraphicContext, ext string) (string, error) {
	// Margin between the image and the frame
	const margin = 30
	// Line width od the frame
	const lineWidth = 3

	// Gopher image
	gopher := samples.Resource("image", "gopher.png", ext)

	// Draw gopher
	err := Draw(gc, gopher, 297, 210, margin, lineWidth)

	// Return the output filename
	return samples.Output("frameimage", ext), err
}
func Main(gc draw2d.GraphicContext, ext string) (string, error) {
	// Margin between the image and the frame
	const margin = 30
	// Line width od the frame
	const lineWidth = 3

	// Gopher image
	gopher := samples.Resource("image", "gopher.png", ext)

	// Draw gopher
	err := Draw(gc, gopher, 297, 210, margin, lineWidth)

	// Return the output filename
	return samples.Output("frameimage", ext), err
}
// Main draws the image frame and returns the filename.
// This should only be used during testing.