I use GeoServer-integrated GeoWebCache,there are some default format :jpg\png\png8\gif ,but no GeoTiff,how can I add this format.I develop 3D-GIS client,my client only support jpg and GeoTiff.When I Get Map with "FORMAT=image/jpeg",the empty area of result jpeg file is not clear,there is always some bad piexl. My question is: 1、can I get the GeoTiff image? 2、can I get rid of the bad piexl?

Please help me!