de5a22aea0
Parameters changed for j2k_decode, jp2_decode, j2k_decode_jpt_stream |
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.. | ||
compat | ||
.cvsignore | ||
convert.c | ||
convert.h | ||
image_to_j2k.c | ||
image_to_j2k.dsp | ||
j2k_to_image.c | ||
j2k_to_image.dsp | ||
Makefile | ||
readme.txt |
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 : --------- * 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 : ------------ -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 " " " " " " "