2004.05.13 08:37 "[Tiff] Easy and low resource rotating of tiff images", by Steven Enderle

2004.05.13 15:13 "Re: [Tiff] Easy and low resource rotating of tiff images", by Richard Morris


Take a look at VIPS (http://www.vips.ecs.soton.ac.uk/). It is a high-performance image processing library. The nice thing about VIPS is that every function can also be called as a command-line utility. Rotating an image by 90 degrees, for example, is as easy as "im_rot90 [input_filename] [output_filename]". It also does automatic format conversion, such as "im_rot90 infile.tif outfile.png".

I will note that I found the best performance by temporarily converting files to the raw VIPS format (filename.v), as in "im_rot90 inputfile.tif temp.v", and then converting the temp file back to tiff with "im_vips2tiff temp.v outputfile.tif". Using those two commands in order generally processed even fairly large TIFF files almost instantly. In addition, to compress those output tiff files, there are various flags, such as "im_vips2tiff temp.v outputfile.tif:packbits", for Packbits compression or "im_vips2tiff temp.v outputfile.tif:jpeg" or even "im_vips2tiff temp.v outputfile.tif:packbits,,,onebit", to convert the output file to one-bit format (the other commas are for additional arguments that can be used, but we are ignoring for now ;-) ).

Hope this helps,

Rick Morris
Application Developer
MOS Imaging Systems
305-779-1247 Direct Line