GENERATEKEYS(1)                   User Manual                  GENERATEKEYS(1)



NAME
       generatekeys - Generate SIFT keypoints from an image file

SYNOPSIS
       generatekeys.exe imagefile keyfile[.gz] [downscaleResolution]

DESCRIPTION
       Generate SIFT key descriptors for an image. It reads in the image file,
       finds SIFT keypoints for descriptive image locations  and  outputs  the
       SIFT  descriptors  to  the  keyfile. The image is internally doubled in
       size, as this increases the number of keypoints found. If  you  do  not
       want  this  behaviour  or  want to downscale the picture, see the down-
       scaleResolution option. The resulting keyfiles can be processed by  the
       other utilities in the autopano-sift package.

OPTIONS
       imagefile
              The  image  file name that will be read in and processed. It can
              be in any format readable by the  GDK  pixbuf  loaders.  Usually
              that includes JPEG, PNG and TIFF.

       keyfile
              The  name  of  the  keypoint XML file to generate. When ".gz" is
              used at the end of the filename, the file is transparently  com-
              pressed using the gzip compression. See gzip(1)

       downscaleResolution
              An  optional  integer width and height limitation. If given, the
              input image is downscaled so its larger  dimension  matches  the
              given size in pixels.  The smaller the downscale resolution, the
              smaller the memory requirements, but  also  less  keypoints  are
              found.  In  case  no downscale resolution is given, the image is
              doubled in size prior to processing, which leads  to  substantly
              more  keypoints.  If  you  use  0 as downscaleResolution you can
              switch this behaviour off and the original image is used without
              applying any scaling.

BUGS
       The  memory  requirements  are quite big. If you have 256Mb of ram, you
       should go with a 700 downscale resolution, if you have 512Mb 1300 is  a
       good value.

AUTHOR
       Sebastian Nowozin <nowozin at cs dot tu dash berlin dot de>

SEE ALSO
       autopano-complete(1), autopano(1), autopanog(1), showone(1), showtwo(1)



autopano-sift                      MAY 2004                    GENERATEKEYS(1)
