1 /* SPMG/JPEG-LS IMPLEMENTATION V.2.1
2 =====================================
3 These programs are Copyright (c) University of British Columbia. All rights reserved.
4 They may be freely redistributed in their entirety provided that this copyright
5 notice is not removed. THEY MAY NOT BE SOLD FOR PROFIT OR INCORPORATED IN
6 COMMERCIAL PROGRAMS WITHOUT THE WRITTEN PERMISSION OF THE COPYRIGHT HOLDER.
7 Each program is provided as is, without any express or implied warranty,
8 without even the warranty of fitness for a particular purpose.
10 =========================================================
11 THIS SOFTWARE IS BASED ON HP's implementation of jpeg-ls:
12 =========================================================
14 LOCO-I/JPEG-LS IMPLEMENTATION V.0.90
15 -------------------------------------------------------------------------------
16 (c) COPYRIGHT HEWLETT-PACKARD COMPANY, 1995-1999.
17 HEWLETT-PACKARD COMPANY ("HP") DOES NOT WARRANT THE ACCURACY OR
18 COMPLETENESS OF THE INFORMATION GIVEN HERE. ANY USE MADE OF, OR
19 RELIANCE ON, SUCH INFORMATION IS ENTIRELY AT USER'S OWN RISK.
20 BY DOWNLOADING THE LOCO-I/JPEG-LS COMPRESSORS/DECOMPRESSORS
21 ("THE SOFTWARE") YOU AGREE TO BE BOUND BY THE TERMS AND CONDITIONS
22 OF THIS LICENSING AGREEMENT.
23 YOU MAY DOWNLOAD AND USE THE SOFTWARE FOR NON-COMMERCIAL PURPOSES
24 FREE OF CHARGE OR FURTHER OBLIGATION. YOU MAY NOT, DIRECTLY OR
25 INDIRECTLY, DISTRIBUTE THE SOFTWARE FOR A FEE, INCORPORATE THIS
26 SOFTWARE INTO ANY PRODUCT OFFERED FOR SALE, OR USE THE SOFTWARE
27 TO PROVIDE A SERVICE FOR WHICH A FEE IS CHARGED.
28 YOU MAY MAKE COPIES OF THE SOFTWARE AND DISTRIBUTE SUCH COPIES TO
29 OTHER PERSONS PROVIDED THAT SUCH COPIES ARE ACCOMPANIED BY
30 HEWLETT-PACKARD'S COPYRIGHT NOTICE AND THIS AGREEMENT AND THAT
31 SUCH OTHER PERSONS AGREE TO BE BOUND BY THE TERMS OF THIS AGREEMENT.
32 THE SOFTWARE IS NOT OF PRODUCT QUALITY AND MAY HAVE ERRORS OR DEFECTS.
33 THE JPEG-LS STANDARD IS STILL UNDER DEVELOPMENT. THE SOFTWARE IS NOT A
34 FINAL OR FULL IMPLEMENTATION OF THE STANDARD. HP GIVES NO EXPRESS OR
35 IMPLIED WARRANTY OF ANY KIND AND ANY IMPLIED WARRANTIES OF
36 MERCHANTABILITY AND FITNESS FOR PURPOSE ARE DISCLAIMED.
37 HP SHALL NOT BE LIABLE FOR ANY DIRECT, INDIRECT, SPECIAL, INCIDENTAL,
38 OR CONSEQUENTIAL DAMAGES ARISING OUT OF ANY USE OF THE SOFTWARE.
39 -------------------------------------------------------------------------------
42 /* initialize.c --- functions to initialize look up tables
43 * and statistics tables
45 * Initial code by Alex Jakulin, Aug. 1995
47 * Modified and optimized: Gadiel Seroussi, October 1995
50 * Modified and added Restart marker and input tables by:
51 * David Cheng-Hsiu Chu, and Ismail R. Ismail march 1999
62 int vLUT[3][2 * LUTMAX16];
64 int classmap[CONTEXTS1];
66 int *qdiv0, *qdiv, /* quantization table (division via look-up) */
67 *qmul0, *qmul; /* dequantization table */
76 /* Setup Look Up Tables for quantized gradient merging */
81 lmax = min(alpha,lutmax);
83 /* implementation limitation: */
85 fprintf(stderr,"Sorry, current implementation does not support threshold T3 > %d, got %d\n",lmax-1,T3);
90 /* Build classification tables (lossless or lossy) */
94 for (i = -lmax + 1; i < lmax; i++) {
96 if ( i <= -T3 ) /* ...... -T3 */
98 else if ( i <= -T2 ) /* -(T3-1) ... -T2 */
100 else if ( i <= -T1 ) /* -(T2-1) ... -T1 */
103 else if ( i <= -1 ) /* -(T1-1) ... -1 */
105 else if ( i == 0 ) /* just 0 */
108 else if ( i < T1 ) /* 1 ... T1-1 */
110 else if ( i < T2 ) /* T1 ... T2-1 */
112 else if ( i < T3 ) /* T2 ... T3-1 */
117 vLUT[0][i + lutmax] = CREGIONS * CREGIONS * idx;
118 vLUT[1][i + lutmax] = CREGIONS * idx;
119 vLUT[2][i + lutmax] = idx;
124 for (i = -lmax + 1; i < lmax; i++) {
126 if ( NEAR >= (alpha-1) )
127 idx = 0; /* degenerate case, regardless of thresholds */
130 if ( i <= -T3 ) /* ...... -T3 */
132 else if ( i <= -T2 ) /* -(T3-1) ... -T2 */
134 else if ( i <= -T1 ) /* -(T2-1) ... -T1 */
137 else if ( i <= -NEAR-1 ) /* -(T1-1) ... -NEAR-1 */
139 else if ( i <= NEAR ) /* within NEAR of 0 */
142 else if ( i < T1 ) /* 1 ... T1-1 */
144 else if ( i < T2 ) /* T1 ... T2-1 */
146 else if ( i < T3 ) /* T2 ... T3-1 */
151 vLUT[0][i + lutmax] = CREGIONS * CREGIONS * idx;
152 vLUT[1][i + lutmax] = CREGIONS * idx;
153 vLUT[2][i + lutmax] = idx;
159 /* prepare context mapping table (symmetric context merging) */
161 for ( i=1, j=0; i<CONTEXTS1; i++) {
162 int q1, q2, q3, n1=0, n2=0, n3=0, ineg, sgn;
167 q1 = i/(CREGIONS*CREGIONS); /* first digit */
168 q2 = (i/CREGIONS)%CREGIONS; /* second digit */
169 q3 = i%CREGIONS; /* third digit */
171 if((q1%2)||(q1==0 && (q2%2))||(q1==0 && q2==0 && (q3%2)))
176 /* compute negative context */
177 if(q1) n1 = q1 + ((q1%2) ? 1 : -1);
178 if(q2) n2 = q2 + ((q2%2) ? 1 : -1);
179 if(q3) n3 = q3 + ((q3%2) ? 1 : -1);
181 ineg = (n1*CREGIONS+n2)*CREGIONS+n3;
182 j++ ; /* next class number */
184 classmap[ineg] = -sgn*j;
195 /* prepare quantization tables for near-lossless quantization */
196 void prepare_qtables(int absize, int NEAR)
204 if ( (qdiv0 = (int *)calloc(2*absize-1,sizeof(int)))==NULL ) {
205 perror("qdiv table");
208 qdiv = qdiv0+absize-1;
210 if ( (qmul0 = (int *)calloc(2*beta-1,sizeof(int)))==NULL ) {
211 perror("qmul table");
216 for ( diff = -(absize-1); diff<absize; diff++ ) {
218 qdiff = - ( (NEAR-diff)/quant );
220 qdiff = ( NEAR + diff )/quant;
223 for ( qdiff = -(beta-1); qdiff<beta; qdiff++ ) {
232 /* Initialize A[], B[], C[], and N[] arrays */
233 void init_stats(int absize)
236 int i, initabstat, slack;
238 slack = 1<<INITABSLACK;
239 initabstat = (absize + slack/2)/slack;
240 if ( initabstat < MIN_INITABSTAT ) initabstat = MIN_INITABSTAT;
242 /* do the statistics initialization */
243 for (i = 0; i < TOT_CONTEXTS; ++i) {