generic-library/openjpeg
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Replaced the large ctxno_mag lookup table with a small bit of inline-able branchless code

Browse Source
This commit is contained in:
Francois-Olivier Devaux
2007-08-21 12:42:55 +00:00
parent 1cfbdcc9ce
commit 2952874cb8
4 changed files with 6 additions and 288 deletions
Download Patch File Download Diff File Expand all files Collapse all files

26
libopenjpeg/t1_generate_luts.c
View File

@@ -146,16 +146,6 @@ static int t1_init_ctxno_sc(int f) {
return (T1_CTXNO_SC + n);
}
static int t1_init_ctxno_mag(int f) {
int n;
if (!(f & T1_REFINE))
n = (f & (T1_SIG_OTH)) ? 1 : 0;
else
n = 2;
return (T1_CTXNO_MAG + n);
}
static int t1_init_spb(int f) {
int hc, vc, n;
@@ -197,7 +187,6 @@ int main(){
double u, v, t;
int lut_ctxno_zc[1024];
int lut_ctxno_mag[4096];
int lut_nmsedec_sig[1 << T1_NMSEDEC_BITS];
int lut_nmsedec_sig0[1 << T1_NMSEDEC_BITS];
int lut_nmsedec_ref[1 << T1_NMSEDEC_BITS];
@@ -229,21 +218,6 @@ int main(){
}
printf("0x%x\n};\n\n", t1_init_ctxno_sc(255 << 4));
// lut_ctxno_mag
for (j = 0; j < 2; ++j) {
for (i = 0; i < 2048; ++i) {
lut_ctxno_mag[(j << 11) + i] = t1_init_ctxno_mag((j ? T1_REFINE : 0) | i);
}
}
printf("static char lut_ctxno_mag[4096] = {\n ");
for (i = 0; i < 4095; ++i) {
printf("%i, ", lut_ctxno_mag[i]);
if(!((i+1)&0xf))
printf("\n ");
}
printf("%i\n};\n\n", lut_ctxno_mag[4095]);
// lut_spb
printf("static char lut_spb[256] = {\n ");
for (i = 0; i < 255; ++i) {