rawTherapee/rtengine/rcd_demosaic.cc
2021-01-24 11:26:04 +01:00

349 lines
18 KiB
C++

/*
* This file is part of RawTherapee.
*
* Copyright (c) 2017-2020 Luis Sanz Rodriguez (luis.sanz.rodriguez(at)gmail(dot)com) and Ingo Weyrich (heckflosse67@gmx.de)
*
* RawTherapee is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* RawTherapee is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with RawTherapee. If not, see <https://www.gnu.org/licenses/>.
*/
#include <cmath>
#include "rawimagesource.h"
#include "rt_math.h"
#include "../rtgui/multilangmgr.h"
#include "StopWatch.h"
using namespace std;
namespace
{
unsigned fc(const unsigned int cfa[2][2], int r, int c) {
return cfa[r & 1][c & 1];
}
}
namespace rtengine
{
/*
* RATIO CORRECTED DEMOSAICING
* Luis Sanz Rodriguez (luis.sanz.rodriguez(at)gmail(dot)com)
*
* Release 2.3 @ 171125
*
* Original code from https://github.com/LuisSR/RCD-Demosaicing
* Licensed under the GNU GPL version 3
*/
// Tiled version by Ingo Weyrich (heckflosse67@gmx.de)
// Luis Sanz Rodriguez significantly optimised the v 2.3 code and simplified the directional
// coefficients in an exact, shorter and more performant formula.
// In cooperation with Hanno Schwalm (hanno@schwalm-bremen.de) and Luis Sanz Rodriguez this has been tuned for performance.
void RawImageSource::rcd_demosaic(size_t chunkSize, bool measure)
{
// Test for RGB cfa
for (int i = 0; i < 2; i++) {
for (int j = 0; j < 2; j++) {
if (FC(i, j) == 3) {
// avoid crash
std::cout << "rcd_demosaic supports only RGB Colour filter arrays. Falling back to igv_interpolate" << std::endl;
igv_interpolate(W, H);
return;
}
}
}
std::unique_ptr<StopWatch> stop;
if (measure) {
std::cout << "Demosaicing " << W << "x" << H << " image using rcd with " << chunkSize << " tiles per thread" << std::endl;
stop.reset(new StopWatch("rcd demosaic"));
}
double progress = 0.0;
if (plistener) {
plistener->setProgressStr(Glib::ustring::compose(M("TP_RAW_DMETHOD_PROGRESSBAR"), M("TP_RAW_RCD")));
plistener->setProgress(progress);
}
const unsigned int cfarray[2][2] = {{FC(0,0), FC(0,1)}, {FC(1,0), FC(1,1)}};
constexpr int tileBorder = 9; // avoid tile-overlap errors
constexpr int rcdBorder = 9;
constexpr int tileSize = 194;
constexpr int tileSizeN = tileSize - 2 * tileBorder;
const int numTh = H / (tileSizeN) + ((H % (tileSizeN)) ? 1 : 0);
const int numTw = W / (tileSizeN) + ((W % (tileSizeN)) ? 1 : 0);
constexpr int w1 = tileSize, w2 = 2 * tileSize, w3 = 3 * tileSize, w4 = 4 * tileSize;
//Tolerance to avoid dividing by zero
constexpr float eps = 1e-5f;
constexpr float epssq = 1e-10f;
constexpr float scale = 65536.f;
#ifdef _OPENMP
#pragma omp parallel
#endif
{
int progresscounter = 0;
float *const cfa = (float*) calloc(tileSize * tileSize, sizeof *cfa);
float (*const rgb)[tileSize * tileSize] = (float (*)[tileSize * tileSize])malloc(3 * sizeof *rgb);
float *const VH_Dir = (float*) calloc(tileSize * tileSize, sizeof *VH_Dir);
float *const PQ_Dir = (float*) calloc(tileSize * tileSize / 2, sizeof *PQ_Dir);
float *const lpf = PQ_Dir; // reuse buffer, they don't overlap in usage
float *const P_CDiff_Hpf = (float*) calloc(tileSize * tileSize / 2, sizeof *P_CDiff_Hpf);
float *const Q_CDiff_Hpf = (float*) calloc(tileSize * tileSize / 2, sizeof *Q_CDiff_Hpf);
#ifdef _OPENMP
#pragma omp for schedule(dynamic, chunkSize) collapse(2) nowait
#endif
for (int tr = 0; tr < numTh; ++tr) {
for (int tc = 0; tc < numTw; ++tc) {
const int rowStart = tr * tileSizeN;
const int rowEnd = std::min(rowStart + tileSize, H);
if (rowStart + tileBorder == rowEnd - tileBorder) {
continue;
}
const int colStart = tc * tileSizeN;
const int colEnd = std::min(colStart + tileSize, W);
if (colStart + tileBorder == colEnd - tileBorder) {
continue;
}
const int tileRows = std::min(rowEnd - rowStart, tileSize);
const int tilecols = std::min(colEnd - colStart, tileSize);
for (int row = rowStart; row < rowEnd; row++) {
const int c0 = fc(cfarray, row, colStart);
const int c1 = fc(cfarray, row, colStart + 1);
for (int col = colStart, indx = (row - rowStart) * tileSize; col < colEnd; ++col, ++indx) {
cfa[indx] = rgb[c0][indx] = rgb[c1][indx] = LIM01(rawData[row][col] / scale);
}
}
// Step 1: Find cardinal and diagonal interpolation directions
float bufferV[3][tileSize - 8];
// Step 1.1: Calculate the square of the vertical and horizontal color difference high pass filter
for (int row = 3; row < std::min(tileRows - 3, 5); ++row) {
for (int col = 4, indx = row * tileSize + col; col < tilecols - 4; ++col, ++indx) {
bufferV[row - 3][col - 4] = SQR((cfa[indx - w3] - cfa[indx - w1] - cfa[indx + w1] + cfa[indx + w3]) - 3.f * (cfa[indx - w2] + cfa[indx + w2]) + 6.f * cfa[indx]);
}
}
// Step 1.2: Obtain the vertical and horizontal directional discrimination strength
float bufferH[tileSize - 6] ALIGNED16;
float* V0 = bufferV[0];
float* V1 = bufferV[1];
float* V2 = bufferV[2];
for (int row = 4; row < tileRows - 4; ++row) {
for (int col = 3, indx = row * tileSize + col; col < tilecols - 3; ++col, ++indx) {
bufferH[col - 3] = SQR((cfa[indx - 3] - cfa[indx - 1] - cfa[indx + 1] + cfa[indx + 3]) - 3.f * (cfa[indx - 2] + cfa[indx + 2]) + 6.f * cfa[indx]);
}
for (int col = 4, indx = (row + 1) * tileSize + col; col < tilecols - 4; ++col, ++indx) {
V2[col - 4] = SQR((cfa[indx - w3] - cfa[indx - w1] - cfa[indx + w1] + cfa[indx + w3]) - 3.f * (cfa[indx - w2] + cfa[indx + w2]) + 6.f * cfa[indx]);
}
for (int col = 4, indx = row * tileSize + col; col < tilecols - 4; ++col, ++indx) {
float V_Stat = std::max(epssq, V0[col - 4] + V1[col - 4] + V2[col - 4]);
float H_Stat = std::max(epssq, bufferH[col - 4] + bufferH[col - 3] + bufferH[col - 2]);
VH_Dir[indx] = V_Stat / (V_Stat + H_Stat);
}
// rotate pointers from row0, row1, row2 to row1, row2, row0
std::swap(V0, V2);
std::swap(V0, V1);
}
// Step 2: Low pass filter incorporating green, red and blue local samples from the raw data
for (int row = 2; row < tileRows - 2; ++row) {
for (int col = 2 + (fc(cfarray, row, 0) & 1), indx = row * tileSize + col, lpindx = indx / 2; col < tilecols - 2; col += 2, indx += 2, ++lpindx) {
lpf[lpindx] = cfa[indx] +
0.5f * (cfa[indx - w1] + cfa[indx + w1] + cfa[indx - 1] + cfa[indx + 1]) +
0.25f * (cfa[indx - w1 - 1] + cfa[indx - w1 + 1] + cfa[indx + w1 - 1] + cfa[indx + w1 + 1]);
}
}
// Step 3: Populate the green channel at blue and red CFA positions
for (int row = 4; row < tileRows - 4; ++row) {
for (int col = 4 + (fc(cfarray, row, 0) & 1), indx = row * tileSize + col, lpindx = indx / 2; col < tilecols - 4; col += 2, indx += 2, ++lpindx) {
// Cardinal gradients
const float cfai = cfa[indx];
const float N_Grad = eps + (std::fabs(cfa[indx - w1] - cfa[indx + w1]) + std::fabs(cfai - cfa[indx - w2])) + (std::fabs(cfa[indx - w1] - cfa[indx - w3]) + std::fabs(cfa[indx - w2] - cfa[indx - w4]));
const float S_Grad = eps + (std::fabs(cfa[indx - w1] - cfa[indx + w1]) + std::fabs(cfai - cfa[indx + w2])) + (std::fabs(cfa[indx + w1] - cfa[indx + w3]) + std::fabs(cfa[indx + w2] - cfa[indx + w4]));
const float W_Grad = eps + (std::fabs(cfa[indx - 1] - cfa[indx + 1]) + std::fabs(cfai - cfa[indx - 2])) + (std::fabs(cfa[indx - 1] - cfa[indx - 3]) + std::fabs(cfa[indx - 2] - cfa[indx - 4]));
const float E_Grad = eps + (std::fabs(cfa[indx - 1] - cfa[indx + 1]) + std::fabs(cfai - cfa[indx + 2])) + (std::fabs(cfa[indx + 1] - cfa[indx + 3]) + std::fabs(cfa[indx + 2] - cfa[indx + 4]));
// Cardinal pixel estimations
const float lpfi = lpf[lpindx];
const float N_Est = cfa[indx - w1] * (lpfi + lpfi) / (eps + lpfi + lpf[lpindx - w1]);
const float S_Est = cfa[indx + w1] * (lpfi + lpfi) / (eps + lpfi + lpf[lpindx + w1]);
const float W_Est = cfa[indx - 1] * (lpfi + lpfi) / (eps + lpfi + lpf[lpindx - 1]);
const float E_Est = cfa[indx + 1] * (lpfi + lpfi) / (eps + lpfi + lpf[lpindx + 1]);
// Vertical and horizontal estimations
const float V_Est = (S_Grad * N_Est + N_Grad * S_Est) / (N_Grad + S_Grad);
const float H_Est = (W_Grad * E_Est + E_Grad * W_Est) / (E_Grad + W_Grad);
// G@B and G@R interpolation
// Refined vertical and horizontal local discrimination
const float VH_Central_Value = VH_Dir[indx];
const float VH_Neighbourhood_Value = 0.25f * ((VH_Dir[indx - w1 - 1] + VH_Dir[indx - w1 + 1]) + (VH_Dir[indx + w1 - 1] + VH_Dir[indx + w1 + 1]));
const float VH_Disc = std::fabs(0.5f - VH_Central_Value) < std::fabs(0.5f - VH_Neighbourhood_Value) ? VH_Neighbourhood_Value : VH_Central_Value;
rgb[1][indx] = intp(VH_Disc, H_Est, V_Est);
}
}
/**
* STEP 4: Populate the red and blue channels
*/
// Step 4.0: Calculate the square of the P/Q diagonals color difference high pass filter
for (int row = 3; row < tileRows - 3; ++row) {
for (int col = 3, indx = row * tileSize + col, indx2 = indx / 2; col < tilecols - 3; col+=2, indx+=2, indx2++ ) {
P_CDiff_Hpf[indx2] = SQR((cfa[indx - w3 - 3] - cfa[indx - w1 - 1] - cfa[indx + w1 + 1] + cfa[indx + w3 + 3]) - 3.f * (cfa[indx - w2 - 2] + cfa[indx + w2 + 2]) + 6.f * cfa[indx]);
Q_CDiff_Hpf[indx2] = SQR((cfa[indx - w3 + 3] - cfa[indx - w1 + 1] - cfa[indx + w1 - 1] + cfa[indx + w3 - 3]) - 3.f * (cfa[indx - w2 + 2] + cfa[indx + w2 - 2]) + 6.f * cfa[indx]);
}
}
// Step 4.1: Obtain the P/Q diagonals directional discrimination strength
for (int row = 4; row < tileRows - 4; ++row) {
for (int col = 4 + (fc(cfarray, row, 0) & 1), indx = row * tileSize + col, indx2 = indx / 2, indx3 = (indx - w1 - 1) / 2, indx4 = (indx + w1 - 1) / 2; col < tilecols - 4; col += 2, indx += 2, indx2++, indx3++, indx4++ ) {
float P_Stat = std::max(epssq, P_CDiff_Hpf[indx3] + P_CDiff_Hpf[indx2] + P_CDiff_Hpf[indx4 + 1]);
float Q_Stat = std::max(epssq, Q_CDiff_Hpf[indx3 + 1] + Q_CDiff_Hpf[indx2] + Q_CDiff_Hpf[indx4]);
PQ_Dir[indx2] = P_Stat / (P_Stat + Q_Stat);
}
}
// Step 4.2: Populate the red and blue channels at blue and red CFA positions
for (int row = 4; row < tileRows - 4; ++row) {
for (int col = 4 + (fc(cfarray, row, 0) & 1), indx = row * tileSize + col, c = 2 - fc(cfarray, row, col), pqindx = indx / 2, pqindx2 = (indx - w1 - 1) / 2, pqindx3 = (indx + w1 - 1) / 2; col < tilecols - 4; col += 2, indx += 2, ++pqindx, ++pqindx2, ++pqindx3) {
// Refined P/Q diagonal local discrimination
float PQ_Central_Value = PQ_Dir[pqindx];
float PQ_Neighbourhood_Value = 0.25f * (PQ_Dir[pqindx2] + PQ_Dir[pqindx2 + 1] + PQ_Dir[pqindx3] + PQ_Dir[pqindx3 + 1]);
float PQ_Disc = (std::fabs(0.5f - PQ_Central_Value) < std::fabs(0.5f - PQ_Neighbourhood_Value)) ? PQ_Neighbourhood_Value : PQ_Central_Value;
// Diagonal gradients
float NW_Grad = eps + std::fabs(rgb[c][indx - w1 - 1] - rgb[c][indx + w1 + 1]) + std::fabs(rgb[c][indx - w1 - 1] - rgb[c][indx - w3 - 3]) + std::fabs(rgb[1][indx] - rgb[1][indx - w2 - 2]);
float NE_Grad = eps + std::fabs(rgb[c][indx - w1 + 1] - rgb[c][indx + w1 - 1]) + std::fabs(rgb[c][indx - w1 + 1] - rgb[c][indx - w3 + 3]) + std::fabs(rgb[1][indx] - rgb[1][indx - w2 + 2]);
float SW_Grad = eps + std::fabs(rgb[c][indx - w1 + 1] - rgb[c][indx + w1 - 1]) + std::fabs(rgb[c][indx + w1 - 1] - rgb[c][indx + w3 - 3]) + std::fabs(rgb[1][indx] - rgb[1][indx + w2 - 2]);
float SE_Grad = eps + std::fabs(rgb[c][indx - w1 - 1] - rgb[c][indx + w1 + 1]) + std::fabs(rgb[c][indx + w1 + 1] - rgb[c][indx + w3 + 3]) + std::fabs(rgb[1][indx] - rgb[1][indx + w2 + 2]);
// Diagonal colour differences
float NW_Est = rgb[c][indx - w1 - 1] - rgb[1][indx - w1 - 1];
float NE_Est = rgb[c][indx - w1 + 1] - rgb[1][indx - w1 + 1];
float SW_Est = rgb[c][indx + w1 - 1] - rgb[1][indx + w1 - 1];
float SE_Est = rgb[c][indx + w1 + 1] - rgb[1][indx + w1 + 1];
// P/Q estimations
float P_Est = (NW_Grad * SE_Est + SE_Grad * NW_Est) / (NW_Grad + SE_Grad);
float Q_Est = (NE_Grad * SW_Est + SW_Grad * NE_Est) / (NE_Grad + SW_Grad);
// R@B and B@R interpolation
rgb[c][indx] = rgb[1][indx] + intp(PQ_Disc, Q_Est, P_Est);
}
}
// Step 4.3: Populate the red and blue channels at green CFA positions
for (int row = 4; row < tileRows - 4; ++row) {
for (int col = 4 + (fc(cfarray, row, 1) & 1), indx = row * tileSize + col; col < tilecols - 4; col += 2, indx += 2) {
// Refined vertical and horizontal local discrimination
float VH_Central_Value = VH_Dir[indx];
float VH_Neighbourhood_Value = 0.25f * ((VH_Dir[indx - w1 - 1] + VH_Dir[indx - w1 + 1]) + (VH_Dir[indx + w1 - 1] + VH_Dir[indx + w1 + 1]));
float VH_Disc = (std::fabs(0.5f - VH_Central_Value) < std::fabs(0.5f - VH_Neighbourhood_Value)) ? VH_Neighbourhood_Value : VH_Central_Value;
float rgb1 = rgb[1][indx];
float N1 = eps + std::fabs(rgb1 - rgb[1][indx - w2]);
float S1 = eps + std::fabs(rgb1 - rgb[1][indx + w2]);
float W1 = eps + std::fabs(rgb1 - rgb[1][indx - 2]);
float E1 = eps + std::fabs(rgb1 - rgb[1][indx + 2]);
float rgb1mw1 = rgb[1][indx - w1];
float rgb1pw1 = rgb[1][indx + w1];
float rgb1m1 = rgb[1][indx - 1];
float rgb1p1 = rgb[1][indx + 1];
for (int c = 0; c <= 2; c += 2) {
// Cardinal gradients
float SNabs = std::fabs(rgb[c][indx - w1] - rgb[c][indx + w1]);
float EWabs = std::fabs(rgb[c][indx - 1] - rgb[c][indx + 1]);
float N_Grad = N1 + SNabs + std::fabs(rgb[c][indx - w1] - rgb[c][indx - w3]);
float S_Grad = S1 + SNabs + std::fabs(rgb[c][indx + w1] - rgb[c][indx + w3]);
float W_Grad = W1 + EWabs + std::fabs(rgb[c][indx - 1] - rgb[c][indx - 3]);
float E_Grad = E1 + EWabs + std::fabs(rgb[c][indx + 1] - rgb[c][indx + 3]);
// Cardinal colour differences
float N_Est = rgb[c][indx - w1] - rgb1mw1;
float S_Est = rgb[c][indx + w1] - rgb1pw1;
float W_Est = rgb[c][indx - 1] - rgb1m1;
float E_Est = rgb[c][indx + 1] - rgb1p1;
// Vertical and horizontal estimations
float V_Est = (N_Grad * S_Est + S_Grad * N_Est) / (N_Grad + S_Grad);
float H_Est = (E_Grad * W_Est + W_Grad * E_Est) / (E_Grad + W_Grad);
// R@G and B@G interpolation
rgb[c][indx] = rgb1 + intp(VH_Disc, H_Est, V_Est);
}
}
}
// For the outermost tiles in all directions we can use a smaller border margin
const int firstVertical = rowStart + ((tr == 0) ? rcdBorder : tileBorder);
const int lastVertical = rowEnd - ((tr == numTh - 1) ? rcdBorder : tileBorder);
const int firstHorizontal = colStart + ((tc == 0) ? rcdBorder : tileBorder);
const int lastHorizontal = colEnd - ((tc == numTw - 1) ? rcdBorder : tileBorder);
for (int row = firstVertical; row < lastVertical; ++row) {
for (int col = firstHorizontal; col < lastHorizontal; ++col) {
int idx = (row - rowStart) * tileSize + col - colStart ;
red[row][col] = std::max(0.f, rgb[0][idx] * scale);
green[row][col] = std::max(0.f, rgb[1][idx] * scale);
blue[row][col] = std::max(0.f, rgb[2][idx] * scale);
}
}
if (plistener) {
progresscounter++;
if (progresscounter % 32 == 0) {
#ifdef _OPENMP
#pragma omp critical (rcdprogress)
#endif
{
progress += (double)32 * ((tileSizeN) * (tileSizeN)) / (H * W);
progress = progress > 1.0 ? 1.0 : progress;
plistener->setProgress(progress);
}
}
}
}
}
free(cfa);
free(rgb);
free(VH_Dir);
free(PQ_Dir);
free(P_CDiff_Hpf);
free(Q_CDiff_Hpf);
}
border_interpolate(W, H, rcdBorder, rawData, red, green, blue);
if (plistener) {
plistener->setProgress(1);
}
}
} /* namespace */