diff options
Diffstat (limited to 'source/blender/compositor/operations/COM_KeyingOperation.cc')
-rw-r--r-- | source/blender/compositor/operations/COM_KeyingOperation.cc | 109 |
1 files changed, 109 insertions, 0 deletions
diff --git a/source/blender/compositor/operations/COM_KeyingOperation.cc b/source/blender/compositor/operations/COM_KeyingOperation.cc new file mode 100644 index 00000000000..94e65181207 --- /dev/null +++ b/source/blender/compositor/operations/COM_KeyingOperation.cc @@ -0,0 +1,109 @@ +/* + * This program 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 2 + * of the License, or (at your option) any later version. + * + * This program 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 this program; if not, write to the Free Software Foundation, + * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. + * + * Copyright 2012, Blender Foundation. + */ + +#include "COM_KeyingOperation.h" + +#include "MEM_guardedalloc.h" + +#include "BLI_listbase.h" +#include "BLI_math.h" + +static float get_pixel_saturation(const float pixelColor[4], + float screen_balance, + int primary_channel) +{ + const int other_1 = (primary_channel + 1) % 3; + const int other_2 = (primary_channel + 2) % 3; + + const int min_channel = MIN2(other_1, other_2); + const int max_channel = MAX2(other_1, other_2); + + const float val = screen_balance * pixelColor[min_channel] + + (1.0f - screen_balance) * pixelColor[max_channel]; + + return (pixelColor[primary_channel] - val) * fabsf(1.0f - val); +} + +KeyingOperation::KeyingOperation() +{ + this->addInputSocket(COM_DT_COLOR); + this->addInputSocket(COM_DT_COLOR); + this->addOutputSocket(COM_DT_VALUE); + + this->m_screenBalance = 0.5f; + + this->m_pixelReader = nullptr; + this->m_screenReader = nullptr; +} + +void KeyingOperation::initExecution() +{ + this->m_pixelReader = this->getInputSocketReader(0); + this->m_screenReader = this->getInputSocketReader(1); +} + +void KeyingOperation::deinitExecution() +{ + this->m_pixelReader = nullptr; + this->m_screenReader = nullptr; +} + +void KeyingOperation::executePixelSampled(float output[4], float x, float y, PixelSampler sampler) +{ + float pixel_color[4]; + float screen_color[4]; + + this->m_pixelReader->readSampled(pixel_color, x, y, sampler); + this->m_screenReader->readSampled(screen_color, x, y, sampler); + + const int primary_channel = max_axis_v3(screen_color); + const float min_pixel_color = min_fff(pixel_color[0], pixel_color[1], pixel_color[2]); + + if (min_pixel_color > 1.0f) { + /* overexposure doesn't happen on screen itself and usually happens + * on light sources in the shot, this need to be checked separately + * because saturation and falloff calculation is based on the fact + * that pixels are not overexposed + */ + output[0] = 1.0f; + } + else { + float saturation = get_pixel_saturation(pixel_color, this->m_screenBalance, primary_channel); + float screen_saturation = get_pixel_saturation( + screen_color, this->m_screenBalance, primary_channel); + + if (saturation < 0) { + /* means main channel of pixel is different from screen, + * assume this is completely a foreground + */ + output[0] = 1.0f; + } + else if (saturation >= screen_saturation) { + /* matched main channels and higher saturation on pixel + * is treated as completely background + */ + output[0] = 0.0f; + } + else { + /* nice alpha falloff on edges */ + float distance = 1.0f - saturation / screen_saturation; + + output[0] = distance; + } + } +} |