17th/18th century painter, 'Portrait of a Bishop'

17th/18th century painter, ‘Portrait of a Bishop’, half-length portrait in blue regalia with cross necklace and book standing at an altar with crucifix, mitre and crosier to the left, lower right coat of arms cartouche with eagle, mitre and three crowns, probably Austria, unsigned, oil on canvas doubl., 99x68 cm. Pressure marks, craquelure and loss of colour, remainder, retouching. With frame. Traces of age.