PngReader added to io

AMDiS/src/io/PngReader.cc

+//
+// Software License for AMDiS
+//
+// Copyright (c) 2010 Dresden University of Technology 
+// All rights reserved.
+// Authors: Simon Vey, Thomas Witkowski et al.
+//
+// This file is part of AMDiS
+//
+// See also license.opensource.txt in the distribution.
+
+#include "PngReader.h"
+#include "png.h"
+
+namespace AMDiS {
+
+  /** \brief
+   * Copies the values of a value file to a DOF vector.
+   */
+  void PngReader::readValue(std::string filename,
+			      DOFVector<double> *vec)
+  {
+    FUNCNAME("ValueReader::readValue()");
+
+    TEST_EXIT(filename != "")("Filename not specified!\n");
+    TEST_EXIT(vec)("no DOF vector specified\n");
+
+    png_structp png_ptr;
+    png_infop info_ptr;
+    FILE *fp;
+    unsigned int sig_read = 0;
+    int row, col, nVertices, nElements;
+    int bytesPerPixel = 0;
+
+    // Open files and create the png data structures.
+    if ((fp = fopen(filename.c_str(), "rb")) == NULL)
+		  TEST_EXIT(0)("ERROR: file can not be opened\n");
+
+    png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
+    if (png_ptr == NULL)
+      TEST_EXIT(0)("ERROR in png_create_read_struct\n");
+
+    info_ptr = png_create_info_struct(png_ptr);
+    if (info_ptr == NULL)
+      TEST_EXIT(0)("ERROR in png_create_info_struct\n");
+
+    if (setjmp(png_jmpbuf(png_ptr)))
+      TEST_EXIT(0)("ERROR in png_jmpbuf\n");
+
+    png_init_io(png_ptr, fp);
+    png_set_sig_bytes(png_ptr, sig_read);
+
+    // Read the whole png at once to the pointer info_ptr.
+    png_read_png(png_ptr, info_ptr, PNG_TRANSFORM_IDENTITY, NULL);
+
+    bytesPerPixel = info_ptr->rowbytes /  info_ptr->width;
+
+    cout << "Read image: " << filename << endl;
+    cout << "Size: " << info_ptr->width << " x " << info_ptr->height << " pixel" << endl;
+    cout << "Bytes per pixel: " << bytesPerPixel << endl;
+
+    double value = 0;
+    const DOFAdmin* admin = vec->getFeSpace()->getAdmin();
+    int n0 = admin->getNumberOfPreDofs(VERTEX); //offset zum globale DOF-managment
+    int dim = vec->getFeSpace()->getMesh()->getDim();
+    int dow = Global::getGeo(WORLD);
+    const BasisFunction *basFcts = vec->getFeSpace()->getBasisFcts();
+    int numBasFcts = basFcts->getNumber();
+    DegreeOfFreedom *localIndices = new DegreeOfFreedom[numBasFcts];
+    
+    TraverseStack stack;
+    ElInfo *elInfo = stack.traverseFirst(vec->getFeSpace()->getMesh(), -1,
+					 Mesh::CALL_LEAF_EL |
+					 Mesh::FILL_COORDS);
+    while (elInfo) {
+      const DegreeOfFreedom **dof = elInfo->getElement()->getDof();
+      Element *el = elInfo->getElement();
+      basFcts->getLocalIndices(el, vec->getFeSpace()->getAdmin(), localIndices);
+      
+      for (int i = 0; i < numBasFcts; i++) {
+	col = static_cast<int>(((elInfo->getCoords())[i][0])*(info_ptr->width-1));
+	row = static_cast<int>((1.0-(elInfo->getCoords())[i][1])*(info_ptr->height-1));
+	switch (bytesPerPixel) {
+	  case 1:
+	    value = static_cast<double>(info_ptr->row_pointers[row][col]);
+	    break;
+	  case 3:
+	    value =
+	      1.0/3.0/255.0 * (static_cast<double>(info_ptr->row_pointers[row][3*col]) +
+		static_cast<double>(info_ptr->row_pointers[row][col*3 + 1]) +
+		static_cast<double>(info_ptr->row_pointers[row][col*3 + 2]));
+	    break;
+	  default:
+	    TEST_EXIT(false)("ERROR: bytesPerPixel=%d is unknown case!\n",bytesPerPixel)
+	}
+	(*vec)[localIndices[i]] = value;
+      }
+      elInfo = stack.traverseNext(elInfo);
+    }
+
+    delete [] localIndices;
+
+    png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+    fclose(fp);
+
+    return(0);
+  }
+}

AMDiS/src/io/PngReader.h

+// ============================================================================
+// ==                                                                        ==
+// == AMDiS - Adaptive multidimensional simulations                          ==
+// ==                                                                        ==
+// ==  http://www.amdis-fem.org                                              ==
+// ==                                                                        ==
+// ============================================================================
+//
+// Software License for AMDiS
+//
+// Copyright (c) 2010 Dresden University of Technology 
+// All rights reserved.
+// Authors: Simon Vey, Thomas Witkowski et al.
+//
+// This file is part of AMDiS
+//
+// See also license.opensource.txt in the distribution.
+
+
+
+/** \file ValueReader.h */
+
+#ifndef AMDIS_VALUEREADER_H
+#define AMDIS_VALUEREADER_H
+
+#include "AMDiS.h"
+
+namespace AMDiS {
+
+  /** \ingroup Input
+   *  
+   * \brief
+   * Static class which reads a png file and gets values for each pixel
+   */ 
+  class PngReader
+  {
+  public:
+    /// Copies the values of a value file to a DOF vector.
+    static void readValue(std::string filename,
+			  DOFVector<double> *dofVector);
+  };
+
+}
+
+#endif