97 lines
2.3 KiB
C++
97 lines
2.3 KiB
C++
//========= Copyright Valve Corporation, All rights reserved. ============//
|
|
//
|
|
// Purpose:
|
|
//
|
|
// $NoKeywords: $
|
|
//
|
|
//=============================================================================//
|
|
#include <quantize.h>
|
|
#include <minmax.h>
|
|
|
|
#define N_EXTRAVALUES 1
|
|
#define N_DIMENSIONS (3+N_EXTRAVALUES)
|
|
|
|
#define PIXEL(x,y,c) Image[4*((x)+((Width*(y))))+c]
|
|
|
|
static uint8 Weights[]={5,7,4,8};
|
|
static int ExtraValueXForms[3*N_EXTRAVALUES]={
|
|
76,151,28,
|
|
};
|
|
|
|
|
|
|
|
#define MAX_QUANTIZE_IMAGE_WIDTH 4096
|
|
|
|
void ColorQuantize(uint8 const *Image,
|
|
int Width,
|
|
int Height,
|
|
int flags, int ncolors,
|
|
uint8 *out_pixels,
|
|
uint8 *out_palette,
|
|
int firstcolor)
|
|
{
|
|
int Error[MAX_QUANTIZE_IMAGE_WIDTH+1][3][2];
|
|
struct Sample *s=AllocSamples(Width*Height,N_DIMENSIONS);
|
|
int x,y,c;
|
|
for(y=0;y<Height;y++)
|
|
for(x=0;x<Width;x++)
|
|
{
|
|
for(c=0;c<3;c++)
|
|
NthSample(s,y*Width+x,N_DIMENSIONS)->Value[c]=PIXEL(x,y,c);
|
|
// now, let's generate extra values to quantize on
|
|
for(int i=0;i<N_EXTRAVALUES;i++)
|
|
{
|
|
int val1=0;
|
|
for(c=0;c<3;c++)
|
|
val1+=PIXEL(x,y,c)*ExtraValueXForms[i*3+c];
|
|
val1>>=8;
|
|
NthSample(s,y*Width+x,N_DIMENSIONS)->Value[c]=(uint8)
|
|
(min(255,max(0,val1)));
|
|
}
|
|
}
|
|
struct QuantizedValue *q=Quantize(s,Width*Height,N_DIMENSIONS,
|
|
ncolors,Weights,firstcolor);
|
|
delete[] s;
|
|
memset(out_palette,0x55,768);
|
|
for(int p=0;p<256;p++)
|
|
{
|
|
struct QuantizedValue *v=FindQNode(q,p);
|
|
if (v)
|
|
for(c=0;c<3;c++)
|
|
out_palette[p*3+c]=v->Mean[c];
|
|
}
|
|
memset(Error,0,sizeof(Error));
|
|
for(y=0;y<Height;y++)
|
|
{
|
|
int ErrorUse=y & 1;
|
|
int ErrorUpdate=ErrorUse^1;
|
|
for(x=0;x<Width;x++)
|
|
{
|
|
uint8 samp[3];
|
|
for(c=0;c<3;c++)
|
|
{
|
|
int tryc=PIXEL(x,y,c);
|
|
if (! (flags & QUANTFLAGS_NODITHER))
|
|
{
|
|
tryc+=Error[x][c][ErrorUse];
|
|
Error[x][c][ErrorUse]=0;
|
|
}
|
|
samp[c]=(uint8) min(255,max(0,tryc));
|
|
}
|
|
struct QuantizedValue *f=FindMatch(samp,3,Weights,q);
|
|
out_pixels[Width*y+x]=(uint8) (f->value);
|
|
if (! (flags & QUANTFLAGS_NODITHER))
|
|
for(int i=0;i<3;i++)
|
|
{
|
|
int newerr=samp[i]-f->Mean[i];
|
|
int orthog_error=(newerr*3)/8;
|
|
Error[x+1][i][ErrorUse]+=orthog_error;
|
|
Error[x][i][ErrorUpdate]=orthog_error;
|
|
Error[x+1][i][ErrorUpdate]=newerr-2*orthog_error;
|
|
}
|
|
}
|
|
}
|
|
if (q) FreeQuantization(q);
|
|
}
|
|
|