virtualx-engine/thirdparty/oidn/core/transfer_function.cpp
jfons dd79d1ce78 Upgrade OpenImageDenoise to v1.1.0
Upgrade OIDN to 1.1.0, the latest stable version that doesn't need
the ISPC compiler.

Documented the changes made during the removal of TBB and added a patch
file for them.
2020-06-06 19:03:16 +02:00

102 lines
3.9 KiB
C++

// ======================================================================== //
// Copyright 2009-2019 Intel Corporation //
// //
// Licensed under the Apache License, Version 2.0 (the "License"); //
// you may not use this file except in compliance with the License. //
// You may obtain a copy of the License at //
// //
// http://www.apache.org/licenses/LICENSE-2.0 //
// //
// Unless required by applicable law or agreed to in writing, software //
// distributed under the License is distributed on an "AS IS" BASIS, //
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. //
// See the License for the specific language governing permissions and //
// limitations under the License. //
// ======================================================================== //
#include "transfer_function.h"
namespace oidn {
const float LogTransferFunction::xScale = 1.f / log(LogTransferFunction::yMax + 1.f);
const float PQXTransferFunction::xScale = 1.f / PQXTransferFunction::pqxForward(PQXTransferFunction::yMax * PQXTransferFunction::yScale);
float AutoexposureNode::autoexposure(const Image& color)
{
assert(color.format == Format::Float3);
// -- GODOT start --
// We don't want to mess with TTB and we don't use autoexposure, so we disable this code
#if 0
// -- GODOT end --
constexpr float key = 0.18f;
constexpr float eps = 1e-8f;
constexpr int K = 16; // downsampling amount
// Downsample the image to minimize sensitivity to noise
const int H = color.height; // original height
const int W = color.width; // original width
const int HK = (H + K/2) / K; // downsampled height
const int WK = (W + K/2) / K; // downsampled width
// Compute the average log luminance of the downsampled image
using Sum = std::pair<float, int>;
Sum sum =
tbb::parallel_reduce(
tbb::blocked_range2d<int>(0, HK, 0, WK),
Sum(0.f, 0),
[&](const tbb::blocked_range2d<int>& r, Sum sum) -> Sum
{
// Iterate over blocks
for (int i = r.rows().begin(); i != r.rows().end(); ++i)
{
for (int j = r.cols().begin(); j != r.cols().end(); ++j)
{
// Compute the average luminance in the current block
const int beginH = int(ptrdiff_t(i) * H / HK);
const int beginW = int(ptrdiff_t(j) * W / WK);
const int endH = int(ptrdiff_t(i+1) * H / HK);
const int endW = int(ptrdiff_t(j+1) * W / WK);
float L = 0.f;
for (int h = beginH; h < endH; ++h)
{
for (int w = beginW; w < endW; ++w)
{
const float* rgb = (const float*)color.get(h, w);
const float r = maxSafe(rgb[0], 0.f);
const float g = maxSafe(rgb[1], 0.f);
const float b = maxSafe(rgb[2], 0.f);
L += luminance(r, g, b);
}
}
L /= (endH - beginH) * (endW - beginW);
// Accumulate the log luminance
if (L > eps)
{
sum.first += log2(L);
sum.second++;
}
}
}
return sum;
},
[](Sum a, Sum b) -> Sum { return Sum(a.first+b.first, a.second+b.second); },
tbb::static_partitioner()
);
return (sum.second > 0) ? (key / exp2(sum.first / float(sum.second))) : 1.f;
// -- GODOT start --
#endif
return 1.0;
// -- GODOT end --
}
} // namespace oidn