opj2_decompress man page

opj_decompress — This program reads in a jpeg2000 image and converts it to another  image type. It is part of the OpenJPEG library.

Valid input image extensions are .j2k, .jp2, .j2c, .jpt

Valid output image extensions are .bmp, .pgm, .pgx, .png, .pnm, .ppm, .raw, .tga, .tif . For PNG resp. TIF it needs libpng resp. libtiff .


opj_decompress -i infile.j2k -o outfile.png

opj_decompress -ImgDir images/ -OutFor bmp

opj_decompress -h Print help message and exit

See Jpwl Options for special options


-i name

(jpeg2000 input file name)

-l n

n is the maximum number of quality layers to decode. See LAYERS below)

-o name

(output file name with extension)

-r n

(n is the highest resolution level to be discarded. See Reduction below)

-x name

(use name as index file and fill it)

-ImgDir directory_name

(directory containing input files)

-OutFor ext

(extension for output files)

Jpip Options

Options usable only if the library has been compiled with BUILD_JPIP


Embed index table box into the output JP2 file (compulsory for JPIP)


Partition a tile into tile parts of different resolution levels (compulsory for JPT-stream)

Jpwl Options

Options usable only if the library has been compiled with BUILD_JPWL

-W c[=Nc] (Nc is the number of expected components in the codestream; default:3)

-W t[=Nt] (Nt is the maximum number of tiles in the codestream; default:8192)

-W c[=Nc], t[=Nt] (same as above)


Set the number of highest resolution levels to be discarded. The image resolution is effectively divided by 2 to the power of the number of discarded levels. The reduce factor is limited by the smallest total number of decomposition levels among tiles.


Set the maximum number of quality layers to decode. If there are less quality layers than the specified number, all the quality layers are decoded.


Copyright (c) 2002-2014, Universite catholique de Louvain (UCL), Belgium
Copyright (c) 2002-2014, Professor Benoit Macq
Copyright (c) 2001-2003, David Janssens
Copyright (c) 2002-2003, Yannick Verschueren
Copyright (c) 2003-2007, Francois-Olivier Devaux and Antonin Descampe
Copyright (c) 2005, Herve Drolon, FreeImage Team
Copyright (c) 2006-2007, Parvatha Elangovan

See Also

opj_compress(1) opj_dump(1)


Version 2.1.1 opj_decompress converts jpeg2000 files