Image compression using the block k-means algorithm
Run make all and make sure that kmeans-compress.sh is marked as executable.
This uses the files from replaceR,
though it can be rewritten to use Rmath.h easily if you prefer that.
It depends on having libtiff and zpaq installed.
On Fedora, I recommend running dnf install libtiff libtiff-devel zpaq zpaq-devel,
as this depends on having libtiff and libzpaq. Appropriate packages are available
in Ubuntu as well.
Basic usage is:
./kmeans-compress.sh -i inputimage.tiff -o outputimage.tiff -p blocksize -k numberofclusters
For example, on the included test image, you may try:
./kmeans-compress.sh -i baboon.tiff -o baboon-test.tiff -p 5 -k 50
There are additional options controlling other settings (method of initialization of clustering,
assigning seeds, etc). It outputs a TIFF version of the compressed image and a file
representing the compressed version of the input image. The program also writes some diagnostic
information to logresults.txt. This works by passing your arguments to block-tiff and then
compressing the output using the zpaq library. The zpaq-compressed output is saved as
outputimage.kmns, taken from the -o argument.
The uncompressed binary files are saved as .out files. A text file,
block-means-text.out, of the first-stage means is provided as well for diagnostic purposes.
There is another program called block-master which takes in a text file representation of an
image which was used for some of the images in the corresponding paper. This is included
for the sake of reproducibility.
Usage: ./block-tiff [-v] -i input-TIFF-file
-o output-TIFF-file
-k number-clusters
[-n] number of tries
-p block size
[-m] initialization method (1 = kmeans||, 2 = kmeans++, 3 = kmeans random starts)
[-r] initialization rounds
[-l] for kmeans|| centers per round
[-L] for kmeans|| multiplication factor (k*L = l), only specify one of L and l
[-s] seed file for PRNG (takes two seeds)
[-S] seed file for PRNG, plus hash of arguments to seed
[-t] uses time(NULL) and getpid() as a seed
Note: -v indicates debugging option, default for -n = 1000, default for -m = 1
default is for L=2 and r=5 for kmeans||
default for kmeans++ is -r 25, default for kmeans random starts is r 1000
default is to hash arguments as a seed
A library of example images will be posted soon with DOI 10.5281/zenodo.3234043 when ready.
write_tiff.*is from http://paulbourke.net/dataformats/tiff/ with no license listed and the note 'Any source code found here may be freely used provided credits are given to the author.'- Mersenne Twister code is from http://www.math.sci.hiroshima-u.ac.jp/~m-mat/MT/emt.html and license
information is found in
mt19937ar.c baboon.tiffis from http://sipi.usc.edu/database/database.php?volume=misc- Everything else is GPLv3 unless otherwise noted.
- See ZPAQ for more information about the lossless compression used here.