tgImageProcessor.cpp

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#include <blort/TomGine/tgImageProcessor.h>
#include <blort/TomGine/tgError.h>
#include <stdexcept>

using namespace TomGine;

tgImageProcessor::tgImageProcessor(     const char *gauss_frag_file,
                                                                        const char *sobel_frag_file,
                                                                        const char *thinning_frag_file,
                                                                        const char *spreading_frag_file,
                                                                        unsigned img_width, unsigned img_height,
                                                                        int avg_resolution)
{
        m_shadeGauss = new tgShader(NULL, gauss_frag_file, NULL);
        m_shadeSobel = new tgShader(NULL, sobel_frag_file, NULL);
        m_shadeThinning = new tgShader(NULL, thinning_frag_file, NULL);
        m_shadeSpreading = new tgShader(NULL, spreading_frag_file, NULL);
        
        init(img_width, img_height);
        initShader((float)img_width, (float)img_height);
        initFBO(avg_resolution);
        tgCheckError("[tgImageProcessor::tgImageProcessor()]");
}

tgImageProcessor::~tgImageProcessor(){
        if(glIsFramebuffer(fbo)) glDeleteFramebuffers(1, &fbo);
        if(glIsTexture(fbo_tex)) glDeleteTextures(1,&fbo_tex);
        if(glIsTexture(fbo_tex_depth)) glDeleteTextures(1,&fbo_tex_depth);

        if(m_shadeGauss) delete(m_shadeGauss);
        if(m_shadeSobel) delete(m_shadeSobel);
        if(m_shadeThinning) delete(m_shadeThinning);
        if(m_shadeSpreading) delete(m_shadeSpreading);
}

// Main initialisation function
void tgImageProcessor::init(unsigned width, unsigned height){
    
        m_width = width;
        m_height = height;

        // Initialise camera
        m_cam_ortho.Set(        0.0f, 0.0f, 1.0f,
                                                0.0f, 0.0f, 0.0f,
                                                0.0f, 1.0f, 0.0f,
                                                45.0f, m_width, m_height,
                                                0.1f, 10.0f,
                                                GL_ORTHO);
}

// Load and compile shaders and set parameters
void tgImageProcessor::initShader(float w, float h){
        float sq2 = 1.0f/sqrt(2.0f);
        
        // offsets of neighbouring pixels in texture coordinates
        GLfloat offX[9] = { -1.0f/w, 0.0, 1.0f/w,
                                                -1.0f/w, 0.0, 1.0f/w,
                                                -1.0f/w, 0.0, 1.0f/w };
        GLfloat offY[9] = {  1.0f/h, 1.0f/h,  1.0f/h,
                                                 0.0,   0.0,    0.0,
                                                -1.0f/h,-1.0f/h, -1.0f/h };
        
        // distance of neighbouring pixels
        GLfloat dist[9] = { sq2, 1.0f, sq2,
                                                1.0f, 0.0f, 1.0f,
                                                sq2, 1.0f, sq2 };
        GLfloat kernel[25] = {  2,  4,  5,  4, 2,
                                                        4,  9, 12,  9, 4,
                                                        5, 12, 15, 12, 5,
                                                        4,  9, 12,  9, 4,
                                                        2,  4,  5,  4, 2 };
        float hi = 10.0f/22; // = sqrt((3+10+3)^2 + (3+10+3)^2) = 22.6
        float lo = 3.0f/22; 
        GLfloat sobelX[9] = {   -lo,    0.0f,   lo,
                                                        -hi,    0.0f,   hi,
                                                        -lo,    0.0f,   lo };
        // dont modify structure of sobelY -> division in sobel.frag
        GLfloat sobelY[9] = {    lo,    hi,     lo,
                                                         0.0f,  0.0f,   0.0f,
                                                        -lo,   -hi,         -lo };
        
        // Gauss shader
        m_shadeGauss->bind();
        m_shadeGauss->setUniform( "kernel", 25, kernel );
        m_shadeGauss->setUniform( "width", w);
        m_shadeGauss->setUniform( "height", h);
        m_shadeGauss->unbind();
        
        // Sobel shader
        m_shadeSobel->bind();
        m_shadeSobel->setUniform( "frame", 0 );
        m_shadeSobel->setUniform( "mask", 1);
        m_shadeSobel->setUniform( "binary", false);
        m_shadeSobel->setUniform( "mOffsetX", mat3(offX), GL_FALSE );
        m_shadeSobel->setUniform( "mOffsetY", mat3(offY), GL_FALSE );
        m_shadeSobel->setUniform( "mSobelX", mat3(sobelX), GL_FALSE );
        m_shadeSobel->setUniform( "mSobelY", mat3(sobelY), GL_FALSE );
        m_shadeSobel->setUniform( "fThreshold", 0.1f );
        m_shadeSobel->unbind();
        
        // Thinning shader
        m_shadeThinning->bind();
        m_shadeThinning->setUniform( "frame", 0 );
        m_shadeThinning->setUniform( "mask", 1);
        m_shadeThinning->setUniform( "mOffsetX", mat3(offX), GL_FALSE );
        m_shadeThinning->setUniform( "mOffsetY", mat3(offY), GL_FALSE );
        m_shadeThinning->setUniform( "fThreshold", 0.1f );
        m_shadeThinning->unbind();
        
        // Spreading shader
        m_shadeSpreading->bind();
        m_shadeSpreading->setUniform( "mOffsetX", mat3(offX), GL_FALSE );
        m_shadeSpreading->setUniform( "mOffsetY", mat3(offY), GL_FALSE );
        m_shadeSpreading->setUniform( "mDistance", mat3(dist), GL_FALSE );
        m_shadeSpreading->setUniform( "fThreshold", 0.1f );
        m_shadeSpreading->setUniform( "fDistScale", 0.5f );
        m_shadeSpreading->unbind();
}

void tgImageProcessor::initFBO(int res)
{
        if(res < 16)
                printf("[tgImageProcessor::avgInit] Warning: resolution too low\n"); // doesn't make sense computing low number of sums on GPU
        
        bool res_valid = false;
        for(unsigned i=4; i<13; i++)
                if(res == pow(2,i))
                        res_valid = true;
        
        if(!res_valid)
                printf("[tgImageProcessor::avgInit] Warning: resolution must be power of 2 and in the range of 16 to 4048\n");
        
        fbo_res = res;
        
        glGenTextures(1, &fbo_tex_depth);
        glBindTexture(GL_TEXTURE_2D, fbo_tex_depth);
        glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR); 
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
        glTexParameteri(GL_TEXTURE_2D, GL_GENERATE_MIPMAP, GL_TRUE); // for attaching to fbo texture must be mipmap complete
//      glTexImage2D( GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT32, fbo_res, fbo_res, 0, GL_DEPTH_COMPONENT, GL_UNSIGNED_BYTE, NULL);
        
        // tgTexture (=memory) for fbo
        glGenTextures(1, &fbo_tex);
        glBindTexture(GL_TEXTURE_2D, fbo_tex);
        glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR); 
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
        glTexParameteri(GL_TEXTURE_2D, GL_GENERATE_MIPMAP, GL_TRUE); // for attaching to fbo texture must be mipmap complete
        glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA32F, fbo_res, fbo_res, 0, GL_RGB, GL_UNSIGNED_BYTE, NULL);
        
        
        // fbo = framebuffer object
        glGenFramebuffers(1,&fbo);
        glBindFramebuffer(GL_FRAMEBUFFER, fbo);
        glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, fbo_tex, 0);
//      glFramebuffertgTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, fbo_tex_depth, 0);
        
        m_cam_ortho_fbo.Set(    0.0f, 0.0f, 1.0f,
                                                        0.0f, 0.0f, 0.0f,
                                                        0.0f, 1.0f, 0.0f,
                                                        45.0f, fbo_res, fbo_res,
                                                        0.0f, 1.0f,
                                                        GL_ORTHO);

        glBindFramebuffer(GL_FRAMEBUFFER, 0);
        
        fbo_stage = ilog2(fbo_res);
        m_avg_init = true;
        
        if(     tgCheckFBError(GL_FRAMEBUFFER, "tgImageProcessor::avgInit()")!=GL_FRAMEBUFFER_COMPLETE ||
                tgCheckError("tgImageProcessor::avgInit()")!=GL_NO_ERROR)
        {
                std::string errmsg = std::string("[tgImageProcessor::initFBO()] Error generating frame buffer objects");
                throw std::runtime_error(errmsg.c_str());
        }
}

void tgImageProcessor::drawQuad(float w, float h){    
        glBegin(GL_QUADS);
                glTexCoord2f(0.0f,0.0f); glVertex3f( 0, 0, 0.0f);
                glTexCoord2f(1.0f,0.0f); glVertex3f( w, 0, 0.0f);
                glTexCoord2f(1.0f,1.0f); glVertex3f( w, h, 0.0f);
                glTexCoord2f(0.0f,1.0f); glVertex3f( 0, h, 0.0f);
        glEnd();
}

// Display list for flipping image upside down
void tgImageProcessor::drawQuadUpsideDown(float w, float h){    
        glBegin(GL_QUADS);
                glTexCoord2f(0.0f,1.0f); glVertex3f( 0, 0, 0.0f);
                glTexCoord2f(1.0f,1.0f); glVertex3f( w, 0, 0.0f);
                glTexCoord2f(1.0f,0.0f); glVertex3f( w, h, 0.0f);
                glTexCoord2f(0.0f,0.0f); glVertex3f( 0, h, 0.0f);
        glEnd();
}

// Set functions
void tgImageProcessor::setCamOrtho(){ 
        m_cam_ortho.Activate();
}

// *** Image Processing functions ***
void tgImageProcessor::flipUpsideDown(const tgTexture& source, tgTexture& result){
        int w = source.GetWidth();
        int h = source.GetHeight();
        m_cam_ortho.Activate();
        glEnable(GL_TEXTURE_2D);
                source.Bind();
                drawQuadUpsideDown(w, h);
                result.CopyTexImage2D(w, h);
        glDisable(GL_TEXTURE_2D);
}

void tgImageProcessor::copy(const tgTexture& source, tgTexture& result){
        int w = source.GetWidth();
        int h = source.GetHeight();
        m_cam_ortho.Activate();
        glEnable(GL_TEXTURE_2D);
                source.Bind();
                drawQuad(w,h);
                result.CopyTexImage2D(w, h);
        glDisable(GL_TEXTURE_2D);
}

void tgImageProcessor::gauss(const tgTexture& source, tgTexture& result){
        int w = source.GetWidth();
        int h = source.GetHeight();
        m_cam_ortho.Activate();
        m_shadeGauss->bind();
        glEnable(GL_TEXTURE_2D);
                source.Bind();
                drawQuad(w,h);
                result.CopyTexImage2D(w, h);
        glDisable(GL_TEXTURE_2D);
        m_shadeGauss->unbind();
}

void tgImageProcessor::sobel(const tgTexture& source, tgTexture& result, float threshold, bool normalise, bool binary){
        int w = source.GetWidth();
        int h = source.GetHeight();
        m_cam_ortho.Activate();
        m_shadeSobel->bind();
        m_shadeSobel->setUniform( "fThreshold", threshold );
        m_shadeSobel->setUniform( "norm", normalise);
        m_shadeSobel->setUniform( "binary", binary);
    glEnable(GL_TEXTURE_2D);
                source.Bind();
                drawQuad(w,h);
                result.CopyTexImage2D(w, h);
        glDisable(GL_TEXTURE_2D);
        m_shadeSobel->unbind();
}

void tgImageProcessor::sobel(const tgTexture& source, tgTexture& result, tgTexture& mask, float threshold, bool normalise, bool binary){
        int w = source.GetWidth();
        int h = source.GetHeight();
        m_cam_ortho.Activate();
        m_shadeSobel->bind();
        m_shadeSobel->setUniform( "fThreshold", threshold );
        m_shadeSobel->setUniform( "norm", normalise);
        m_shadeSobel->setUniform( "masked", true);
        m_shadeSobel->setUniform( "binary", binary);
        glEnable(GL_TEXTURE_2D);
                source.Bind(0);
                mask.Bind(1);
                drawQuad(w,h);
                result.CopyTexImage2D(w, h);
        glDisable(GL_TEXTURE_2D);
        m_shadeSobel->unbind();
        m_shadeSobel->setUniform( "masked", false);
}

void tgImageProcessor::thinning(const tgTexture& source, tgTexture& result){
        int w = source.GetWidth();
        int h = source.GetHeight();
        m_cam_ortho.Activate();
        m_shadeThinning->bind();
        glEnable(GL_TEXTURE_2D);
                source.Bind();
                drawQuad(w,h);
        result.CopyTexImage2D(w, h);
    glDisable(GL_TEXTURE_2D);
        m_shadeThinning->unbind();
}

void tgImageProcessor::thinning(const tgTexture& source, tgTexture& result, tgTexture& mask){
        int w = source.GetWidth();
        int h = source.GetHeight();
        m_cam_ortho.Activate();
        m_shadeThinning->bind();
        m_shadeThinning->setUniform( "masked", true);
        glEnable(GL_TEXTURE_2D);
                source.Bind(0);
                mask.Bind(1);
                drawQuad(w,h);
        result.CopyTexImage2D(w, h);
    glDisable(GL_TEXTURE_2D);
        m_shadeThinning->setUniform( "masked", false);
        m_shadeThinning->unbind();
}

void tgImageProcessor::spreading(const tgTexture& source, tgTexture& result){
        int w = source.GetWidth();
        int h = source.GetHeight();
        m_cam_ortho.Activate();
        m_shadeSpreading->bind();
        glEnable(GL_TEXTURE_2D);
                source.Bind();
                drawQuad(w,h);
        result.CopyTexImage2D(w, h);
    glDisable(GL_TEXTURE_2D);
        m_shadeSpreading->unbind();
}

void tgImageProcessor::render(const tgTexture& tex){
        m_cam_ortho.Activate();
        glEnable(GL_TEXTURE_2D);
                tex.Bind();
                drawQuad(tex.GetWidth(), tex.GetHeight());
        glDisable(GL_TEXTURE_2D);
}

void tgImageProcessor::avgActivate(){
        if(m_avg_init){
                glBindFramebuffer(GL_FRAMEBUFFER, fbo);
                tgCheckError("tgImageProcessor::avgActivate() A");
                glClearColor(0,0,0,0);
                glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
                tgCheckError("tgImageProcessor::avgActivate() B");
        }
}

void tgImageProcessor::avgGet(float *avg, int lvl){
        if(m_avg_init){
                if(lvl==0){
                        // for some reason glGetTexImage doesen't get the value of the very last mipmap stage
//                      float tmp[16];
//                      glBindtgTexture(GL_TEXTURE_2D, fbo_tex);
//                      glGenerateMipmap(GL_TEXTURE_2D);
//                      glGetTexImage(GL_TEXTURE_2D, fbo_stage-1, GL_RGBA, GL_FLOAT, tmp);
//                      avg[0] = 0;
//                      for(unsigned i=0; i<4; i++)
//                              avg[0] += 0.25 * tmp[i];
                        printf("[tgImageProcessor::avgGet] Warning: not implemented\n");
                }else{
                        glBindTexture(GL_TEXTURE_2D, fbo_tex);
//                      glCopyTexImage2D(GL_TEXTURE_2D, 0, GL_RGB16,0, 0, fbo_res,fbo_res,0);
                        glGenerateMipmap(GL_TEXTURE_2D);
                        glGetTexImage(GL_TEXTURE_2D, fbo_stage-lvl, GL_RED, GL_FLOAT, avg);
                        tgCheckError("tgImageProcessor::avgGet()");
                }
        }
}

void tgImageProcessor::avgDeactivate(){
        if(m_avg_init){
                glBindFramebuffer(GL_FRAMEBUFFER, 0);
        }
}