'Insert an image with its top-left corner in a worksheet cell.
Args:
row:      The cell row (zero indexed).
col:      The cell column (zero indexed).
filename: Path and filename for image in PNG, JPG or BMP format.
options:  Position, scale, url and data stream of the image.
Returns:
0:  Success.'

@convert_cell_args
def insert_image(self, row, col, filename, options=None):

    if (options is None):
        options = {}
    x_offset = options.get('x_offset', 0)
    y_offset = options.get('y_offset', 0)
    x_scale = options.get('x_scale', 1)
    y_scale = options.get('y_scale', 1)
    url = options.get('url', None)
    tip = options.get('tip', None)
    anchor = options.get('positioning', None)
    image_data = options.get('image_data', None)
    if ((not image_data) and (not os.path.exists(filename))):
        warn(("Image    file    '%s'    not    found." % force_unicode(filename)))
        return (-1)
    self.images.append([row, col, filename, x_offset, y_offset, x_scale, y_scale, url, tip, anchor, image_data])
