JurassicParkTrespasser/jp2_pc/Source/Tools/QuantizerTool/NEUQUANT.C
2018-01-01 23:07:24 +01:00

488 lines
11 KiB
C

// several changes (mainly x86 and quality optimizations) by wili/hybrid 1996
/* NeuQuant Neural-Net Quantization Algorithm
* ------------------------------------------
*
* Copyright (c) 1994 Anthony Dekker
*
* NEUQUANT Neural-Net quantization algorithm by Anthony Dekker, 1994.
* See "Kohonen neural networks for optimal colour quantization"
* in "Network: Computation in Neural Systems" Vol. 5 (1994) pp 351-367.
* for a discussion of the algorithm.
*
* Any party obtaining a copy of these files from the author, directly or
* indirectly, is granted, free of charge, a full and unrestricted irrevocable,
* world-wide, paid up, royalty-free, nonexclusive right and license to deal
* in this software and documentation files (the "Software"), including without
* limitation the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons who receive
* copies from any such party to do so, with the only requirement being
* that this copyright notice remain intact.
*/
#include "neuquant.h"
#include <math.h>
extern void check_abort();
/* Network Definitions
------------------- */
#define maxnetpos (netsize-1)
#define netbiasshift 4 /* bias for colour values */
#define ncycles 100 /* no. of learning cycles */
/* defs for freq and bias */
#define intbiasshift 16 /* bias for fractions */
#define intbias (((int) 1)<<intbiasshift)
#define gammashift 10 /* gamma = 1024 */
#define gamma (((int) 1)<<gammashift)
#define betashift 10
#define beta (intbias>>betashift) /* beta = 1/1024 */
#define betagamma (intbias<<(gammashift-betashift))
/* defs for decreasing radius factor */
#define initrad (netsize>>3) /* for 256 cols, radius starts */
#define radiusbiasshift 6 /* at 32.0 biased by 6 bits */
#define radiusbias (((int) 1)<<radiusbiasshift)
#define initradius (initrad*radiusbias) /* and decreases by a */
#define radiusdec 30 /* factor of 1/30 each cycle */
/* defs for decreasing alpha factor */
#define alphabiasshift 10 /* alpha starts at 1.0 */
#define initalpha (((int) 1)<<alphabiasshift)
int alphadec; /* biased by 10 bits */
/* radbias and alpharadbias used for radpower calculation */
#define radbiasshift 8
#define radbias (((int) 1)<<radbiasshift)
#define alpharadbshift (alphabiasshift+radbiasshift)
#define alpharadbias (((int) 1)<<alpharadbshift)
/* Types and Global Variables
-------------------------- */
static unsigned char *thepicture; /* the input image itself */
static int lengthcount; /* lengthcount = H*W*3 */
static int samplefac; /* sampling factor 1..30 */
typedef int pixel[4]; /* BGRc */
static pixel network[netsize]; /* the network itself */
static int netindex[256]; /* for network lookup - really 256 */
static int bias [netsize]; /* bias and freq arrays for learning */
static int freq [netsize];
static int radpower[initrad]; /* radpower for precomputation */
/* Initialise network in range (0,0,0) to (255,255,255) and set parameters
----------------------------------------------------------------------- */
void initnet(unsigned char *thepic,int len,int sample)
{
int i;
int *p;
thepicture = thepic;
lengthcount = len;
samplefac = sample;
for (i=0; i<netsize; i++)
{
p = network[i];
p[0] = p[1] = p[2] = (i << (netbiasshift+8))/netsize;
freq[i] = intbias/netsize; /* 1/netsize */
bias[i] = 0;
}
}
/* Unbias network to give byte values 0..255 and record position i to prepare for sort
----------------------------------------------------------------------------------- */
void unbiasnet()
{
int i,j;
for (i=0; i<netsize; i++)
{
for (j=0; j<3; j++)
network[i][j] >>= netbiasshift;
network[i][3] = i; /* record colour no */
}
}
/* Output colour map
----------------- */
void copy_colourmap( char *dest)
{
int i,j;
for (i=2; i>=0; i--)
for (j=0; j<netsize; j++)
dest[j*3+i]= network[j][i];
}
/* Insertion sort of network and building of netindex[0..255] (to do after unbias)
------------------------------------------------------------------------------- */
void inxbuild()
{
int i,j,smallpos,smallval;
int *p,*q;
int previouscol,startpos;
previouscol = 0;
startpos = 0;
for (i=0; i<netsize; i++)
{
p = network[i];
smallpos = i;
smallval = p[1]; /* index on g */
/* find smallest in i..netsize-1 */
for (j=i+1; j<netsize; j++)
{
q = network[j];
if (q[1] < smallval)
{
smallpos = j;
smallval = q[1]; /* index on g */
}
}
q = network[smallpos];
/* swap p (i) and q (smallpos) entries */
if (i != smallpos)
{
j = q[0]; q[0] = p[0]; p[0] = j;
j = q[1]; q[1] = p[1]; p[1] = j;
j = q[2]; q[2] = p[2]; p[2] = j;
j = q[3]; q[3] = p[3]; p[3] = j;
}
/* smallval entry is now in position i */
if (smallval != previouscol)
{
netindex[previouscol] = (startpos+i)>>1;
for (j=previouscol+1; j<smallval; j++)
netindex[j] = i;
previouscol = smallval;
startpos = i;
}
}
netindex[previouscol] = (startpos+maxnetpos)/2;
for (j=previouscol+1; j<256; j++)
netindex[j] = maxnetpos; /* really 256 */
}
char inxsearch(int b, int g, int r)
{
int i,j,dist,a;
int *p;
int best = -1;
int bestd = 1000000;
i = netindex[g]; /* index on g */
j = i-1; /* start at netindex[g] and work outwards */
while ((i<netsize) || (j>=0))
{
if (i<netsize)
{
p = network[i];
dist = (p[1] - g); /* inx key */
if (dist >= bestd)
i = netsize; /* stop iter */
else
{
i++;
dist=abs(dist)+abs(p[2]-r); // 0 b
if (dist<bestd)
{
dist += abs(p[0]-b); // 2 r
if (dist<bestd)
{
bestd = dist;
best = p[3];
}
}
}
}
if (j>=0)
{
p = network[j];
dist = (g - p[1]); /* inx key - reverse dif */
if (dist >= bestd)
j = -1; /* stop iter */
else
{
j--;
dist=abs(dist)+abs(p[2]-r); // 0 b
if (dist<bestd)
{
dist += abs(p[0]-b); // 2 r
if (dist<bestd)
{
bestd = dist;
best = p[3];
}
}
}
}
}
return(best);
}
/* Search for biased BGR values
---------------------------- */
#define SQR(x) ((x)*(x))
int contest(int b,int g,int r)
{
/* finds closest neuron (min dist) and updates freq */
/* finds best neuron (min dist-bias) and returns position */
/* for frequently chosen neurons, freq[i] is high and bias[i] is negative */
/* bias[i] = gamma*((1/netsize)-freq[i]) */
int i,dist,a,biasdist,betafreq;
int bestpos,bestbiaspos,bestd,bestbiasd;
int *p,*f, *n;
bestd = ~(((int) 1)<<31);
bestbiasd = bestd;
bestpos = -1;
bestbiaspos = bestpos;
p = bias;
f = freq;
for (i=0; i<netsize; i++)
{
n = network[i];
dist = (SQR(n[2]-r)*30+SQR(n[1]-g)*59+SQR(n[0]-b)*11);
// dist = abs(n[0] - b) + abs(n[1]-g) + abs(n[2]-r); // original
if (dist<bestd)
{
bestd=dist;
bestpos=i;
}
biasdist = dist - ((*p)>>(intbiasshift-netbiasshift));
if (biasdist<bestbiasd)
{
bestbiasd=biasdist;
bestbiaspos=i;
}
betafreq = (*f >> betashift);
*f++ -= betafreq;
*p++ += (betafreq<<gammashift);
}
freq[bestpos] += beta;
bias[bestpos] -= betagamma;
return(bestbiaspos);
}
int FTOI(float foo);
#pragma aux FTOI = \
"push eax"\
"fistp dword ptr [esp]" \
"pop eax" \
parm [8087] value [eax];
/* Move neuron i towards biased (b,g,r) by factor alpha
---------------------------------------------------- */
void altersingle(int alpha,int i,int b,int g,int r)
{
int *n;
float f;
n = network[i]; /* alter hit neuron */
f = alpha*(1.0/(float)initalpha);
n[0] -= FTOI((n[0] - b)*f);
n[1] -= FTOI((n[1] - g)*f);
n[2] -= FTOI((n[2] - r)*f);
}
/* Move adjacent neurons by precomputed alpha*(1-((i-j)^2/[r]^2)) in radpower[|i-j|]
--------------------------------------------------------------------------------- */
void alterneigh (int rad, int i, int b, int g, int r)
{
int j,k,lo,hi;
int *p, *q;
float mul;
lo = i-rad;
if (lo<-1)
lo=-1;
hi = i+rad;
if (hi>netsize)
hi=netsize;
j = i+1;
k = i-1;
q = radpower;
while ((j<hi) || (k>lo))
{
mul = (float)(*(++q))/alpharadbias;
if (j<hi)
{
p = network[j];
p[0] -= FTOI((p[0]-b)*mul);
p[1] -= FTOI((p[1]-g)*mul);
p[2] -= FTOI((p[2]-r)*mul);
j++;
}
if (k>lo)
{
p = network[k];
p[0] -= FTOI ((p[0]-b)*mul);
p[1] -= FTOI ((p[1]-g)*mul);
p[2] -= FTOI ((p[2]-r)*mul);
k--;
}
}
}
/* Main Learning Loop
------------------ */
void learn()
{
int i,j,b,g,r;
int radius,rad,alpha,step,delta,samplepixels,r2;
unsigned char *p;
unsigned char *lim;
int percadd,perc;
alphadec = 30 + ((samplefac-1)/3);
p = thepicture;
lim = thepicture + lengthcount;
samplepixels = lengthcount/(3*samplefac);
delta = samplepixels/ncycles;
alpha = initalpha;
radius = initradius;
rad = radius >> radiusbiasshift;
if (rad <= 1)
rad = 0;
for (i=0; i<rad; i++)
radpower[i] = alpha*(((rad*rad - i*i)*radbias)/(rad*rad));
if ((lengthcount%prime1))
step = 3*prime1;
else
{
if ((lengthcount%prime2))
step = 3*prime2;
else
{
if ((lengthcount%prime3))
step = 3*prime3;
else
step = 3*prime4;
}
}
i = 0;
percadd = (samplepixels/70);
perc = percadd;
while (i < samplepixels)
{
if (i>perc)
{
check_abort();
printf("%cLearning (%d%%)",13,(i*100)/samplepixels);
perc = i+percadd;
fflush(stdout);
}
b = p[0] << netbiasshift;
g = p[1] << netbiasshift;
r = p[2] << netbiasshift;
j = contest(b,g,r);
altersingle(alpha,j,b,g,r);
if (rad)
alterneigh(rad,j,b,g,r); /* alter neighbours */
p += step;
if (p >= lim)
p -= lengthcount;
i++;
if (!(i%delta))
{
alpha -= alpha / alphadec;
radius -= radius / radiusdec;
rad = radius >> radiusbiasshift;
if (rad <= 1)
rad = 0;
r2 = rad*rad;
for (j=0; j<rad; j++)
radpower[j] = alpha*(((r2 - j*j)*radbias)/r2);
}
}
}