Tone-mapping and OpenMP see issue1670

This commit is contained in:
jdc
2013-01-07 13:08:15 +01:00
parent 989cfb5fbd
commit 658c06b03d
2 changed files with 72 additions and 34 deletions

View File

@@ -1,6 +1,9 @@
#include <cmath>
#include "rt_math.h"
#include "EdgePreservingDecomposition.h"
#ifdef _OPENMP
#include <omp.h>
#endif
/* Solves A x = b by the conjugate gradient method, where instead of feeding it the matrix A you feed it a function which
calculates A x where x is some vector. Stops when rms residual < RMSResidual or when maximum iterates is reached.
@@ -12,25 +15,33 @@ float *SparseConjugateGradient(void Ax(float *Product, float *x, void *Pass), fl
float *x, float RMSResidual, void *Pass, unsigned int MaximumIterates, void Preconditioner(float *Product, float *x, void *Pass)){
unsigned int iterate, i;
//Start r and x.
float *r = new float[n];
//Start r and x.
if(x == NULL){
x = new float[n];
memset(x, 0, sizeof(float)*n); //Zero initial guess if x == NULL.
memcpy(r, b, sizeof(float)*n);
}else{
Ax(r, x, Pass);
for(i = 0; i != n; i++) r[i] = b[i] - r[i]; //r = b - A x.
#ifdef _OPENMP
#pragma omp parallel for schedule(dynamic,10)
#endif
for(int ii = 0; ii < n; ii++) r[ii] = b[ii] - r[ii]; //r = b - A x.
}
//s is preconditionment of r. Without, direct to r.
float *s = r, rs = 0.0f;
float *s = r, rs = 0.0f, fp=0.f;
if(Preconditioner != NULL){
s = new float[n];
Preconditioner(s, r, Pass);
}
for(i = 0; i != n; i++) rs += r[i]*s[i];
#ifdef _OPENMP
#pragma omp parallel for schedule(dynamic,10) firstprivate(fp) reduction(+:rs)
#endif
for(int ii = 0; ii < n; ii++) {
fp = r[ii]*s[ii];
rs=rs+fp;
}
//Search direction d.
float *d = new float[n];
memcpy(d, s, sizeof(float)*n);
@@ -41,21 +52,21 @@ float *SparseConjugateGradient(void Ax(float *Product, float *x, void *Pass), fl
//Start iterating!
if(MaximumIterates == 0) MaximumIterates = n;
for(iterate = 0; iterate != MaximumIterates; iterate++){
for(iterate = 0; iterate < MaximumIterates; iterate++){
//Get step size alpha, store ax while at it.
float ab = 0.0f;
Ax(ax, d, Pass);
for(i = 0; i != n; i++) ab += d[i]*ax[i];
for(int ii = 0; ii < n; ii++) ab += d[ii]*ax[ii];
if(ab == 0.0f) break; //So unlikely. It means perfectly converged or singular, stop either way.
ab = rs/ab;
//Update x and r with this step size.
float rms = 0.0;
for(i = 0; i != n; i++){
x[i] += ab*d[i];
r[i] -= ab*ax[i]; //"Fast recursive formula", use explicit r = b - Ax occasionally?
rms += r[i]*r[i];
for(int ii = 0; ii < n; ii++){
x[ii] += ab*d[ii];
r[ii] -= ab*ax[ii]; //"Fast recursive formula", use explicit r = b - Ax occasionally?
rms += r[ii]*r[ii];
}
rms = sqrtf(rms/n);
//printf("%f\n", rms);
@@ -67,12 +78,13 @@ float *SparseConjugateGradient(void Ax(float *Product, float *x, void *Pass), fl
//Get beta.
ab = rs;
rs = 0.0f;
for(i = 0; i != n; i++) rs += r[i]*s[i];
for(int ii = 0; ii < n; ii++) rs += r[ii]*s[ii];
ab = rs/ab;
//Update search direction p.
for(i = 0; i != n; i++) d[i] = s[i] + ab*d[i];
for(int ii = 0; ii < n; ii++) d[ii] = s[ii] + ab*d[ii];
}
if(iterate == MaximumIterates)
if(iterate != n && RMSResidual != 0.0f)
printf("Warning: MaximumIterates (%u) reached in SparseConjugateGradient.\n", MaximumIterates);
@@ -84,7 +96,6 @@ float *SparseConjugateGradient(void Ax(float *Product, float *x, void *Pass), fl
return x;
}
MultiDiagonalSymmetricMatrix::MultiDiagonalSymmetricMatrix(unsigned int Dimension, unsigned int NumberOfDiagonalsInLowerTriangle){
n = Dimension;
m = NumberOfDiagonalsInLowerTriangle;
@@ -183,20 +194,27 @@ bool MultiDiagonalSymmetricMatrix::CreateIncompleteCholeskyFactorization(unsigne
//How many diagonals in the decomposition?
MaxFillAbove++; //Conceptually, now "fill" includes an existing diagonal. Simpler in the math that follows.
unsigned int i, j, mic;
for(mic = i = 1; i != m; i++)
mic += rtengine::min(StartRows[i] - StartRows[i - 1], MaxFillAbove); //Guarunteed positive since StartRows must be created in increasing order.
unsigned int i, j, mic, fp;
mic=1;
fp=1;
#ifdef _OPENMP
#pragma omp parallel for schedule(dynamic,10) firstprivate(fp) reduction(+:mic)
#endif
for(int ii = 1; ii < m; ii++) {
fp = rtengine::min(StartRows[ii] - StartRows[ii - 1], MaxFillAbove); //Guarunteed positive since StartRows must be created in increasing order.
mic=mic+fp;
}
//Initialize the decomposition - setup memory, start rows, etc.
MultiDiagonalSymmetricMatrix *ic = new MultiDiagonalSymmetricMatrix(n, mic);
ic->CreateDiagonal(0, 0); //There's always a main diagonal in this type of decomposition.
for(mic = i = 1; i != m; i++){
mic=1;
for(int ii = 1; ii < m; ii++){
//Set j to the number of diagonals to be created corresponding to a diagonal on this source matrix...
j = rtengine::min(StartRows[i] - StartRows[i - 1], MaxFillAbove);
j = rtengine::min(StartRows[ii] - StartRows[ii - 1], MaxFillAbove);
//...and create those diagonals. I want to take a moment to tell you about how much I love minimalistic loops: very much.
while(j-- != 0)
if(!ic->CreateDiagonal(mic++, StartRows[i] - j)){
if(!ic->CreateDiagonal(mic++, StartRows[ii] - j)){
//Beware of out of memory, possible for large, sparse problems if you ask for too much fill.
printf("Error in MultiDiagonalSymmetricMatrix::CreateIncompleteCholeskyFactorization: Out of memory. Ask for less fill?\n");
delete ic;
@@ -350,12 +368,16 @@ float *EdgePreservingDecomposition::CreateBlur(float *Source, float Scale, float
if(UseBlurForEdgeStop) a = new float[n], g = Blur;
else a = Blur, g = Source;
unsigned int x, y, i;
//unsigned int x, y;
unsigned int i;
unsigned int w1 = w - 1, h1 = h - 1;
float eps = 0.02f;
for(y = 0; y != h1; y++){
#ifdef _OPENMP
#pragma omp parallel for schedule(dynamic,10)
#endif
for(int y = 0; y < h1; y++){
float *rg = &g[w*y];
for(x = 0; x != w1; x++){
for(int x = 0; x < w1; x++){
//Estimate the central difference gradient in the center of a four pixel square. (gx, gy) is actually 2*gradient.
float gx = (rg[x + 1] - rg[x]) + (rg[x + w + 1] - rg[x + w]);
float gy = (rg[x + w] - rg[x]) + (rg[x + w + 1] - rg[x + 1]);
@@ -364,7 +386,7 @@ float *EdgePreservingDecomposition::CreateBlur(float *Source, float Scale, float
a[x + w*y] = Scale*powf(0.5f*sqrtf(gx*gx + gy*gy + eps*eps), -EdgeStopping);
}
}
//unsigned int x,y;
/* Now setup the linear problem. I use the Maxima CAS, here's code for making an FEM formulation for the smoothness term:
p(x, y) := (1 - x)*(1 - y);
P(m, n) := A[m][n]*p(x, y) + A[m + 1][n]*p(1 - x, y) + A[m + 1][n + 1]*p(1 - x, 1 - y) + A[m][n + 1]*p(x, 1 - y);
@@ -379,6 +401,7 @@ float *EdgePreservingDecomposition::CreateBlur(float *Source, float Scale, float
memset(a_w1, 0, A->DiagonalLength(w - 1)*sizeof(float));
memset(a_w, 0, A->DiagonalLength(w)*sizeof(float));
memset(a_w_1, 0, A->DiagonalLength(w + 1)*sizeof(float));
unsigned int x, y;
for(i = y = 0; y != h; y++){
for(x = 0; x != w; x++, i++){
float ac;
@@ -403,6 +426,7 @@ float *EdgePreservingDecomposition::CreateBlur(float *Source, float Scale, float
a0[i] += 4.0f*a[i]/6.0f;
}
}
if(UseBlurForEdgeStop) delete[] a;
//Solve & return.
@@ -428,7 +452,7 @@ float *EdgePreservingDecomposition::CreateIteratedBlur(float *Source, float Scal
//Iteratively improve the blur.
Reweightings++;
for(unsigned int i = 0; i != Reweightings; i++)
for(unsigned int i = 0; i < Reweightings; i++)
CreateBlur(Source, Scale, EdgeStopping, Iterates, Blur, true);
return Blur;
@@ -440,21 +464,29 @@ float *EdgePreservingDecomposition::CompressDynamicRange(float *Source, float Sc
//We're working with luminance, which does better logarithmic.
unsigned int i;
for(i = 0; i != n; i++)
Source[i] = logf(Source[i] + eps);
#ifdef _OPENMP
#pragma omp parallel for schedule(dynamic,10)
#endif
for(int ii = 0; ii < n; ii++)
Source[ii] = logf(Source[ii] + eps);
//Blur. Also setup memory for Compressed (we can just use u since each element of u is used in one calculation).
float *u = CreateIteratedBlur(Source, Scale, EdgeStopping, Iterates, Reweightings);
if(Compressed == NULL) Compressed = u;
//Apply compression, detail boost, unlogging. Compression is done on the logged data and detail boost on unlogged.
for(int i = 0; i != n; i++){
#ifdef _OPENMP
#pragma omp parallel for schedule(dynamic,10)
#endif
for(int i = 0; i < n; i++){
float ce = expf(Source[i] + u[i]*(CompressionExponent - 1.0f)) - eps;
float ue = expf(u[i]) - eps;
Source[i] = expf(Source[i]) - eps;
Compressed[i] = ce + DetailBoost*(Source[i] - ue);
}
if(Compressed != u) delete[] u;
return Compressed;
}

View File

@@ -2679,6 +2679,9 @@ if(!params->edgePreservingDecompositionUI.enabled) return;
//Restore past range, also desaturate a bit per Mantiuk's Color correction for tone mapping.
float s = (1.0f + 38.7889f)*powf(Compression, 1.5856f)/(1.0f + 38.7889f*powf(Compression, 1.5856f));
#ifndef _DEBUG
#pragma omp parallel for schedule(dynamic,10)
#endif
for (int i=0; i<Hei; i++)
for (int j=0; j<Wid; j++) {
ncie->Q_p[i][j]=(Qpr[i*Wid+j]+eps)*Qpro;
@@ -2773,10 +2776,13 @@ fclose(f);*/
//Restore past range, also desaturate a bit per Mantiuk's Color correction for tone mapping.
float s = (1.0f + 38.7889f)*powf(Compression, 1.5856f)/(1.0f + 38.7889f*powf(Compression, 1.5856f));
for(i = 0; i != N; i++)
a[i] *= s,
b[i] *= s,
L[i] = L[i]*32767.0f + minL;
#ifdef _OPENMP
#pragma omp parallel for schedule(dynamic,10)
#endif
for(int ii = 0; ii < N; ii++)
a[ii] *= s,
b[ii] *= s,
L[ii] = L[ii]*32767.0f + minL;
}