Install the imagemagick utiltities to convert from/to PPM:
brew install imagemagick # for Mac OSX
(use the convert utility to convert to/from PPM)
If desired, install the libtiff library (just for support reading TIFF):
brew install libtiff # for Mac OSX
Build (including OpenHTJ2K):
export BLOSC=/absolute/path/to/c-blosc2
make build
Then a number of commands from OpenHTJ2K will be available:
mkdir output
./bin/open_htj2k_enc -i input/teapot.ppm -o output/teapot.j2c
./bin/open_htj2k_enc -i input/teapot.ppm -o output/teapot.jphc
./bin/open_htj2k_dec -i output/teapot.jphc -o output/teapot.ppm
Using the OpenHTJ2K plugin is possible via the main program. For Mac:
DYLD_LIBRARY_PATH=$BLOSC/build/blosc ./a.out
Read OK
Register OK
Blosc version info: 2.6.2.dev ($Date:: 2022-12-15 #$)
Write OK
and the roundtrip file should appear in the output directory:
ls -l output
total 141216
-rw-r--r--@ 1 faltet staff 72000017 Jan 27 13:17 pexels-artem-saranin-1496373.ppm
-rw-r--r-- 1 faltet staff 45605 Jan 27 12:21 teapot.j2c
-rw-r--r-- 1 faltet staff 45690 Jan 27 12:24 teapot.jphc
-rw-r--r-- 1 faltet staff 196623 Jan 27 13:14 teapot.ppm
JPEG 2000 (J2K-1 block coder)
- Part 1 .JP2 file format
- Part 1 .J2K or .J2C or .JPC code stream
- Part 2 Extensions .JPX or .JPF file format
- Part 3 Motion .MJ2 file format
- Part 6 Compound .JPM file format
- Part 15 HT .JPH file format
- Part 15 HT .JHC or .JPHC code stream
We use .JPHC