diff options
Diffstat (limited to 'source/blender/compositor/operations/COM_ChromaMatteOperation.cpp')
| -rw-r--r-- | source/blender/compositor/operations/COM_ChromaMatteOperation.cpp | 97 |
1 files changed, 97 insertions, 0 deletions
diff --git a/source/blender/compositor/operations/COM_ChromaMatteOperation.cpp b/source/blender/compositor/operations/COM_ChromaMatteOperation.cpp new file mode 100644 index 00000000000..8e793f08a3b --- /dev/null +++ b/source/blender/compositor/operations/COM_ChromaMatteOperation.cpp @@ -0,0 +1,97 @@ +/* + * Copyright 2011, Blender Foundation. + * + * 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. + * + * Contributor: + * Dalai Felinto + */ + +#include "COM_ChromaMatteOperation.h" +#include "BLI_math.h" + +ChromaMatteOperation::ChromaMatteOperation(): NodeOperation() { + addInputSocket(COM_DT_COLOR); + addInputSocket(COM_DT_COLOR); + addOutputSocket(COM_DT_VALUE); + + inputImageProgram = NULL; + inputKeyProgram = NULL; +} + +void ChromaMatteOperation::initExecution() { + this->inputImageProgram = this->getInputSocketReader(0); + this->inputKeyProgram = this->getInputSocketReader(1); +} + +void ChromaMatteOperation::deinitExecution() { + this->inputImageProgram= NULL; + this->inputKeyProgram= NULL; +} + +void ChromaMatteOperation::executePixel(float* outputValue, float x, float y, PixelSampler sampler, MemoryBuffer *inputBuffers[]) { + float inKey[4]; + float inImage[4]; + + const float acceptance = this->settings->t1; /* in radians */ + const float cutoff = this->settings->t2; /* in radians */ + const float gain = this->settings->fstrength; + + float x_angle, z_angle, alpha; + float theta, beta; + float kfg; + + this->inputKeyProgram->read(inKey, x, y, sampler, inputBuffers); + this->inputImageProgram->read(inImage, x, y, sampler, inputBuffers); + + /* store matte(alpha) value in [0] to go with + * COM_SetAlphaOperation and the Value output + */ + + /* Algorithm from book "Video Demistified," does not include the spill reduction part */ + /* find theta, the angle that the color space should be rotated based on key*/ + theta=atan2(inKey[2], inKey[1]); + + /*rotate the cb and cr into x/z space */ + x_angle=inImage[1]*cosf(theta)+inImage[2]*sinf(theta); + z_angle=inImage[2]*cosf(theta)-inImage[1]*sinf(theta); + + /*if within the acceptance angle */ + /* if kfg is <0 then the pixel is outside of the key color */ + kfg= x_angle-(fabsf(z_angle)/tanf(acceptance/2.f)); + + if(kfg>0.f) { /* found a pixel that is within key color */ + alpha=(1.f-kfg)*(gain); + + beta=atan2(z_angle,x_angle); + + /* if beta is within the cutoff angle */ + if(fabsf(beta) < (cutoff/2.f)) { + alpha=0.f; + } + + /* don't make something that was more transparent less transparent */ + if (alpha<inImage[3]) { + outputValue[0]=alpha; + } + else { + outputValue[0]=inImage[3]; + } + } + else { /*pixel is outside key color */ + outputValue[0]=inImage[3]; /* make pixel just as transparent as it was before */ + } +} + |