Initial import
git-svn-id: http://moon:8086/svn/software/trunk/libsrc/libtiff_2007@1 b431acfa-c32f-4a4a-93f1-934dc6c82436
This commit is contained in:
Executable
+161
@@ -0,0 +1,161 @@
|
||||
float ycbcrCoeffs[3] = { .299, .587, .114 };
|
||||
/* default coding range is CCIR Rec 601-1 with no headroom/footroom */
|
||||
unsigned long refBlackWhite[6] = { 0, 255, 128, 255, 128, 255 };
|
||||
|
||||
#define LumaRed ycbcrCoeffs[0]
|
||||
#define LumaGreen ycbcrCoeffs[1]
|
||||
#define LumaBlue ycbcrCoeffs[2]
|
||||
|
||||
long eRtotal = 0;
|
||||
long eGtotal = 0;
|
||||
long eBtotal = 0;
|
||||
long preveRtotal = 0;
|
||||
long preveGtotal = 0;
|
||||
long preveBtotal = 0;
|
||||
unsigned long AbseRtotal = 0;
|
||||
unsigned long AbseGtotal = 0;
|
||||
unsigned long AbseBtotal = 0;
|
||||
unsigned long eCodes = 0;
|
||||
unsigned long preveCodes = 0;
|
||||
unsigned long eBits = 0;
|
||||
unsigned long preveBits = 0;
|
||||
|
||||
static void setupLumaTables();
|
||||
static int abs(int v) { return (v < 0 ? -v : v); }
|
||||
static double pct(int v,double range) { return (v*100. / range); }
|
||||
static void check(int R, int G, int B);
|
||||
|
||||
float D1, D2;
|
||||
float D3, D4;
|
||||
float D5, D6;
|
||||
|
||||
int
|
||||
main(int argc, char* argv)
|
||||
{
|
||||
int R, G, B;
|
||||
|
||||
if (argc > 1) {
|
||||
refBlackWhite[0] = 16;
|
||||
refBlackWhite[1] = 235;
|
||||
refBlackWhite[2] = 128;
|
||||
refBlackWhite[3] = 240;
|
||||
refBlackWhite[4] = 128;
|
||||
refBlackWhite[5] = 240;
|
||||
}
|
||||
D3 = 2 - 2*LumaRed;
|
||||
D4 = 2 - 2*LumaBlue;
|
||||
D1 = 1. / D3;
|
||||
D2 = 1. / D4;
|
||||
D5 = D3*LumaRed / LumaGreen;
|
||||
D6 = D4*LumaBlue / LumaGreen;
|
||||
setupLumaTables();
|
||||
for (R = 0; R < 256; R++) {
|
||||
for (G = 0; G < 256; G++)
|
||||
for (B = 0; B < 256; B++)
|
||||
check(R, G, B);
|
||||
printf("[%3u] c %u/%u b %u/%u (R %u/%d/%u G %u/%d/%u B %u/%d/%u)\n"
|
||||
, R
|
||||
, eCodes - preveCodes, eCodes
|
||||
, eBits - preveBits, eBits
|
||||
, abs(AbseRtotal - preveRtotal), eRtotal , AbseRtotal
|
||||
, abs(AbseGtotal - preveGtotal), eGtotal , AbseGtotal
|
||||
, abs(AbseBtotal - preveBtotal), eBtotal , AbseBtotal
|
||||
);
|
||||
preveRtotal = AbseRtotal;
|
||||
preveGtotal = AbseGtotal;
|
||||
preveBtotal = AbseBtotal;
|
||||
preveCodes = eCodes;
|
||||
preveBits = eBits;
|
||||
}
|
||||
printf("%u total codes\n", 256*256*256);
|
||||
printf("total error: %u codes %u bits (R %d/%u G %d/%u B %d/%u)\n"
|
||||
, eCodes
|
||||
, eBits
|
||||
, eRtotal , AbseRtotal
|
||||
, eGtotal , AbseGtotal
|
||||
, eBtotal , AbseBtotal
|
||||
);
|
||||
return (0);
|
||||
}
|
||||
|
||||
float *lumaRed;
|
||||
float *lumaGreen;
|
||||
float *lumaBlue;
|
||||
|
||||
static float*
|
||||
setupLuma(float c)
|
||||
{
|
||||
float *v = (float *)_TIFFmalloc(256 * sizeof (float));
|
||||
int i;
|
||||
for (i = 0; i < 256; i++)
|
||||
v[i] = c * i;
|
||||
return (v);
|
||||
}
|
||||
|
||||
static void
|
||||
setupLumaTables(void)
|
||||
{
|
||||
lumaRed = setupLuma(LumaRed);
|
||||
lumaGreen = setupLuma(LumaGreen);
|
||||
lumaBlue = setupLuma(LumaBlue);
|
||||
}
|
||||
|
||||
static unsigned
|
||||
V2Code(float f, unsigned long RB, unsigned long RW, int CR)
|
||||
{
|
||||
unsigned int c = (unsigned int)((((f)*(RW-RB)/CR)+RB)+.5);
|
||||
return (c > 255 ? 255 : c);
|
||||
}
|
||||
|
||||
#define Code2V(c, RB, RW, CR) ((((c)-(int)RB)*(float)CR)/(float)(RW-RB))
|
||||
|
||||
#define CLAMP(f,min,max) \
|
||||
(int)((f)+.5 < (min) ? (min) : (f)+.5 > (max) ? (max) : (f)+.5)
|
||||
|
||||
static
|
||||
void
|
||||
check(int R, int G, int B)
|
||||
{
|
||||
float Y, Cb, Cr;
|
||||
int iY, iCb, iCr;
|
||||
float rY, rCb, rCr;
|
||||
float rR, rG, rB;
|
||||
int eR, eG, eB;
|
||||
|
||||
Y = lumaRed[R] + lumaGreen[G] + lumaBlue[B];
|
||||
Cb = (B - Y)*D2;
|
||||
Cr = (R - Y)*D1;
|
||||
iY = V2Code(Y, refBlackWhite[0], refBlackWhite[1], 255);
|
||||
iCb = V2Code(Cb, refBlackWhite[2], refBlackWhite[3], 127);
|
||||
iCr = V2Code(Cr, refBlackWhite[4], refBlackWhite[5], 127);
|
||||
rCb = Code2V(iCb, refBlackWhite[2], refBlackWhite[3], 127);
|
||||
rCr = Code2V(iCr, refBlackWhite[4], refBlackWhite[5], 127);
|
||||
rY = Code2V(iY, refBlackWhite[0], refBlackWhite[1], 255);
|
||||
rR = rY + rCr*D3;
|
||||
rB = rY + rCb*D4;
|
||||
rG = rY - rCb*D6 - rCr*D5;
|
||||
eR = R - CLAMP(rR,0,255);
|
||||
eG = G - CLAMP(rG,0,255);
|
||||
eB = B - CLAMP(rB,0,255);
|
||||
if (abs(eR) > 1 || abs(eG) > 1 || abs(eB) > 1) {
|
||||
printf("R %u G %u B %u", R, G, B);
|
||||
printf(" Y %g Cb %g Cr %g", Y, Cb, Cr);
|
||||
printf(" iY %u iCb %u iCr %u", iY, iCb, iCr);
|
||||
printf("\n -> Y %g Cb %g Cr %g", rY, rCb, rCr);
|
||||
printf(" R %g (%u) G %g (%u) B %g (%u) E=[%d %d %d])\n"
|
||||
, rR, CLAMP(rR,0,255)
|
||||
, rG, CLAMP(rG,0,255)
|
||||
, rB, CLAMP(rB,0,255)
|
||||
, eR, eG, eB
|
||||
);
|
||||
}
|
||||
eRtotal += eR;
|
||||
eGtotal += eG;
|
||||
eBtotal += eB;
|
||||
AbseRtotal += abs(eR);
|
||||
AbseGtotal += abs(eG);
|
||||
AbseBtotal += abs(eB);
|
||||
if (eR | eG | eB)
|
||||
eCodes++;
|
||||
eBits += abs(eR) + abs(eG) + abs(eB);
|
||||
}
|
||||
Reference in New Issue
Block a user