List of parameters for the coder JPEG 2000 :
Date : June the 25th, 2003
Author : Yannick Verschueren
Contact : verschueren@tele.ucl.ac.be
- the option -help displays the readme.txt file on screen
- The markers COD and QCD are writed both of two in the main_header and never appear in the tile_header. The markers in the main header are : SOC SIZ COD QCD COM.
- This coder can encode mega image, a test was made on a 24000x24000 pixels color image. You need enough disk space memory (twice the original) to encode the image. (i.e. for a 1.5 Gb image you need a minimum of 3Gb of disk memory)
REMARKS :
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* the value of rate enter in the code line is the compression factor !
exemple :
-r 20,10,1 means quality 1 : compress 20x, quality 2 : compress 10x and quality 3 : compress 1x = lossless
* The number of resolution can be modified by the program in view to respect profile-0 conditions (Taubman, Marcelin (2002), "JPEG2000, image compression fundamentals, standards and practice", p700)
By default :
------------
* lossless
* 1 tile
* size of precinct 2^15 x 2^15 (means 1 precinct)
* size of code-block 64 x 64
* Number of resolution : 6
* No SOP marker in the codestream
* No EPH marker in the codestream
* No sub-sampling in x and y direction
* No mode switch activated
* progression order : LRCP
* No index file
* No ROI upshifted
* No offset of the origin of the image
* No offset of the origin of the tiles
* Reversible DWT 5-3
Parameters :
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-i : source file (-i source.pnm also *.pgm, *.ppm) "required"
-o : destination file (-o dest.j2k) "required"
-r : different rates (-r 20,10,5) "optional"
-n : Number of resolution (-n 3) "optional"
-b : size of code block (-b 32,32) "optional"
-c : size of precinct (-c 128,128) "optional"
-t : size of tile (-t 512,512) "optional"
-p : progression order (-p LRCP) [LRCP, RLCP, RPCL, PCRL, CPRL] "optional"
-s : subsampling factor (-s 2,2) [-s X,Y] "optional"
-SOP : write SOP marker before each packet "optional"
-EPH : write EPH marker after each header packet "optional"
-M : mode switch (-M 3) [1= BYPASS(LAZY) 2=RESET 4=RESTART(TERMALL) 8=VSC 16=ERTERM(SEGTERM) 32=SEGMARK(SEGSYM)] "optional"
for several mode switch you have to add the value of each mode you want
ex : RESTART(4) + RESET(2) + SEGMARK(32) = -M 38
-x : Create an index file *.Idx (-x index_name.Idx) "optional"
-ROI:c=%d,U=%d : quantization indices upshifted for component c=%d [%d = 0,1,2]
with a value of U=%d [0 <= %d <= 37] (i.e. -ROI:c=0,U=25) "optional"
-d : offset of the origin of the image (-d 150,300) "optional"
-T : offset of the origin of the tiles (-T 100,75) "optional"
-I : Use the irreversible DWT 9-7 (-I) "optional"
IMPORTANT :
-----------
* subsampling bigger than 2 can produce error
The index file respect the structure below :
---------------------------------------------
Image_height Image_width
progression order
Tiles_size_X Tiles_size_Y
Components_nb
Layers_nb
decomposition_levels
Precincts_size_X Precincts_size_Y
Main_header_end_position
Codestream_size
Tile0 start_pos end_Theader end_pos
Tile1 " " "
...
TileN " " "
Tpacket_0 Tile layer res. comp. prec. start_pos end_pos
...
Tpacket_M " " " " " " "
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