We are getting a thumbnailer error on a png file of 16 Mpx. This error is: "Error creating thumbnail: Invalid thumbnail parameters". It appears there is an upper bound limitation somewhere, since Wikipedia has a similar problem (e.g., see http://en.wikipedia.org/wiki/ Category:Old_Ordnance_Survey_map_images).
Is this a hard limit due to limitations of Imagemagick or is there a global that controls the upper bound on image size that the thumbnailer can handle?