Files
test/source/blender/compositor/operations/COM_PixelateOperation.cc
Sergey Sharybin baab14ca38 Compositor: Re-write Pixelate node for CPU compositor
The old implementation was a simple rounding operation and was not
implemented for full-frame compositor.

The issue with the old implementation is that it will not give
satisfactory results for images with high frequency details,
including cases when is used for a preview on Cycles render with
low number of samples. Additionally, when applied on animated
footage it produces very noisy result.

The new algorithm uses an explicit pixel size setting, which allows
the node to be used on its own, without need to have scale-down and
scale-up nodes. It also uses neighbour averaging, which produces
better looking result during animation and noisy input images.

The old tiled compositor setup will render without changes with
this change. This commit does not include modifications in the GPU
compositor implementation.

Ref #88150

Pull Request: https://projects.blender.org/blender/blender/pulls/117223
2024-01-18 11:30:55 +01:00

127 lines
3.6 KiB
C++

/* SPDX-FileCopyrightText: 2011 Blender Authors
*
* SPDX-License-Identifier: GPL-2.0-or-later */
#include "COM_PixelateOperation.h"
#include <algorithm>
namespace blender::compositor {
PixelateOperation::PixelateOperation()
{
this->add_input_socket(DataType::Color);
this->add_output_socket(DataType::Color);
this->set_canvas_input_index(0);
input_operation_ = nullptr;
flags_.can_be_constant = true;
pixel_size_ = 1;
}
void PixelateOperation::init_execution()
{
input_operation_ = this->get_input_socket_reader(0);
}
void PixelateOperation::deinit_execution()
{
input_operation_ = nullptr;
}
bool PixelateOperation::determine_depending_area_of_interest(rcti *input,
ReadBufferOperation *read_operation,
rcti *output)
{
rcti new_input;
new_input.xmin = input->xmin;
new_input.xmax = input->xmax + pixel_size_ - 1;
new_input.ymax = input->ymax;
new_input.ymax = input->ymax + pixel_size_ - 1;
return NodeOperation::determine_depending_area_of_interest(&new_input, read_operation, output);
}
void PixelateOperation::execute_pixel_sampled(float output[4],
const float x,
const float y,
const PixelSampler sampler)
{
const int width = this->get_width();
const int height = this->get_height();
const int x_start = (int(x) / pixel_size_) * pixel_size_;
const int y_start = (int(y) / pixel_size_) * pixel_size_;
const int x_end = std::min(x_start + pixel_size_, width);
const int y_end = std::min(y_start + pixel_size_, height);
float4 color_accum(0, 0, 0, 0);
for (int iy = y_start; iy < y_end; ++iy) {
for (int ix = x_start; ix < x_end; ++ix) {
float4 color;
input_operation_->read_sampled(color, ix, iy, sampler);
color_accum += color;
}
}
const int scale = (x_end - x_start) * (y_end - y_start);
copy_v4_v4(output, color_accum / float(scale));
}
void PixelateOperation::get_area_of_interest(const int /*input_idx*/,
const rcti &output_area,
rcti &r_input_area)
{
r_input_area.xmin = output_area.xmin;
r_input_area.ymin = output_area.ymin;
r_input_area.xmax = output_area.xmax + pixel_size_ - 1;
r_input_area.ymax = output_area.ymax + pixel_size_ - 1;
}
void PixelateOperation::update_memory_buffer_partial(MemoryBuffer *output,
const rcti &area,
Span<MemoryBuffer *> inputs)
{
MemoryBuffer *image = inputs[0];
if (image->is_a_single_elem()) {
copy_v4_v4(output->get_elem(0, 0), image->get_elem(0, 0));
return;
}
const int width = image->get_width();
const int height = image->get_height();
for (BuffersIterator<float> it = output->iterate_with(inputs, area); !it.is_end(); ++it) {
const int x_start = (it.x / pixel_size_) * pixel_size_;
const int y_start = (it.y / pixel_size_) * pixel_size_;
const int x_end = std::min(x_start + pixel_size_, width);
const int y_end = std::min(y_start + pixel_size_, height);
float4 color_accum(0, 0, 0, 0);
for (int y = y_start; y < y_end; ++y) {
for (int x = x_start; x < x_end; ++x) {
float4 color;
image->read_elem(x, y, color);
color_accum += color;
}
}
const int scale = (x_end - x_start) * (y_end - y_start);
copy_v4_v4(it.out, color_accum / float(scale));
}
}
} // namespace blender::compositor