--- /dev/null
+
+//////////////////////////////////////////////////////////////////////////////////
+// This program is free software: you can redistribute it and/or modify //
+// it under the terms of the version 3 of the GNU General Public License //
+// as published by the Free Software Foundation. //
+// //
+// 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, see <http://www.gnu.org/licenses/>. //
+// //
+// Written by Francois Fleuret //
+// (C) Ecole Polytechnique Federale de Lausanne //
+// Contact <pom@epfl.ch> for comments & bug reports //
+//////////////////////////////////////////////////////////////////////////////////
+
+#include <iostream>
+#include <stdio.h>
+
+using namespace std;
+
+#include <libpng/png.h>
+
+#include "rgb_image.h"
+
+void RGBImage::allocate() {
+ _bit_plans = new unsigned char **[RGB_DEPTH];
+ _bit_lines = new unsigned char *[RGB_DEPTH * _height];
+ _bit_map = new unsigned char [_width * _height * RGB_DEPTH];
+ for(int k = 0; k < RGB_DEPTH; k++) _bit_plans[k] = _bit_lines + k * _height;
+ for(int k = 0; k < RGB_DEPTH * _height; k++) _bit_lines[k] = _bit_map + k * _width;
+}
+
+void RGBImage::deallocate() {
+ delete[] _bit_plans;
+ delete[] _bit_lines;
+ delete[] _bit_map;
+}
+
+RGBImage::RGBImage() : _bit_plans(0), _bit_lines(0), _bit_map(0) { }
+
+RGBImage::RGBImage(int width, int height) : _width(width), _height(height) {
+ allocate();
+ memset(_bit_map, 0, _width * _height * RGB_DEPTH * sizeof(unsigned char));
+}
+
+RGBImage::~RGBImage() {
+ deallocate();
+}
+
+void RGBImage::write_ppm(const char *filename) {
+ FILE *outfile;
+
+ if ((outfile = fopen (filename, "wb")) == 0) {
+ fprintf (stderr, "Can't open %s for reading\n", filename);
+ exit(1);
+ }
+
+ fprintf(outfile, "P6\n%d %d\n255\n", _width, _height);
+
+ char *raw = new char[_width * _height * 3];
+
+ int k = 0;
+ for(int y = 0; y < _height; y++) for(int x = 0; x < _width; x++) {
+ raw[k++] = _bit_map[x + _width * (y + _height * RED)];
+ raw[k++] = _bit_map[x + _width * (y + _height * GREEN)];
+ raw[k++] = _bit_map[x + _width * (y + _height * BLUE)];
+ }
+
+ fwrite((void *) raw, sizeof(unsigned char), _width * _height * 3, outfile);
+ fclose(outfile);
+
+ delete[] raw;
+}
+
+void RGBImage::read_ppm(const char *filename) {
+ const int buffer_size = 1024;
+ FILE *infile;
+ char buffer[buffer_size];
+ int max;
+
+ deallocate();
+
+ if((infile = fopen (filename, "r")) == 0) {
+ fprintf (stderr, "Can't open %s for reading\n", filename);
+ exit(1);
+ }
+
+ fgets(buffer, buffer_size, infile);
+
+ if(strncmp(buffer, "P6", 2) == 0) {
+
+ do {
+ fgets(buffer, buffer_size, infile);
+ } while((buffer[0] < '0') || (buffer[0] > '9'));
+ sscanf(buffer, "%d %d", &_width, &_height);
+ fgets(buffer, buffer_size, infile);
+ sscanf(buffer, "%d", &max);
+
+ allocate();
+
+ unsigned char *raw = new unsigned char[_width * _height * RGB_DEPTH];
+ fread(raw, sizeof(unsigned char), _width * _height * RGB_DEPTH, infile);
+
+ int k = 0;
+ for(int y = 0; y < _height; y++) for(int x = 0; x < _width; x++) {
+ _bit_plans[RED][y][x] = raw[k++];
+ _bit_plans[GREEN][y][x] = raw[k++];
+ _bit_plans[BLUE][y][x] = raw[k++];
+ }
+
+ delete[] raw;
+
+ } else if(strncmp(buffer, "P5", 2) == 0) {
+
+ do {
+ fgets(buffer, buffer_size, infile);
+ } while((buffer[0] < '0') || (buffer[0] > '9'));
+ sscanf(buffer, "%d %d", &_width, &_height);
+ fgets(buffer, buffer_size, infile);
+ sscanf(buffer, "%d", &max);
+
+ allocate();
+
+ unsigned char *pixbuf = new unsigned char[_width * _height];
+ fread(buffer, sizeof(unsigned char), _width * _height, infile);
+
+ int k = 0, l = 0;
+ for(int y = 0; y < _height; y++) for(int x = 0; x < _width; x++) {
+ unsigned char c = pixbuf[k++];
+ _bit_map[l++] = c;
+ _bit_map[l++] = c;
+ _bit_map[l++] = c;
+ }
+
+ delete[] pixbuf;
+
+ } else {
+ cerr << "Can not read ppm of type [" << buffer << "] from " << filename << ".\n";
+ exit(1);
+ }
+}
+
+void RGBImage::read_png(const char* filename) {
+ // This is the number of bytes the read_png routine will read to
+ // decide if the file is a PNG or not. According to the png
+ // documentation, it can be 1 to 8 bytes, 8 being the max and the
+ // best.
+
+ const int header_size = 8;
+
+ png_byte header[header_size];
+ png_bytep *row_pointers;
+
+ deallocate();
+
+ // open file
+ FILE *fp = fopen(filename, "rb");
+ if (!fp) {
+ cerr << "Unable to open file " << filename << " for reading.\n";
+ exit(1);
+ }
+
+ // read header
+ fread(header, 1, header_size, fp);
+ if (png_sig_cmp(header, 0, header_size)) {
+ cerr << "File " << filename << " does not look like PNG.\n";
+ fclose(fp);
+ exit(1);
+ }
+
+ // create png pointer
+ png_structp png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, 0, 0, 0);
+ if (!png_ptr) {
+ cerr << "png_create_read_struct failed\n";
+ fclose(fp);
+ exit(1);
+ }
+
+ // create png info struct
+ png_infop info_ptr = png_create_info_struct(png_ptr);
+ if (!info_ptr) {
+ png_destroy_read_struct(&png_ptr, (png_infopp) 0, (png_infopp) 0);
+ cerr << "png_create_info_struct failed\n";
+ fclose(fp);
+ exit(1);
+ }
+
+ // get image info
+ png_init_io(png_ptr, fp);
+ png_set_sig_bytes(png_ptr, header_size);
+ png_read_info(png_ptr, info_ptr);
+
+ _width = info_ptr->width;
+ _height = info_ptr->height;
+
+ png_byte bit_depth, color_type, channels;
+ color_type = info_ptr->color_type;
+ bit_depth = info_ptr->bit_depth;
+ channels = info_ptr->channels;
+
+ if(bit_depth != 8) {
+ cerr << "Can only read 8-bits PNG images." << endl;
+ exit(1);
+ }
+
+ // allocate image pointer
+ row_pointers = (png_bytep*) malloc(sizeof(png_bytep) * _height);
+ for (int y = 0; y < _height; y++)
+ row_pointers[y] = (png_byte*) malloc(info_ptr->rowbytes);
+
+ allocate();
+
+ // read image
+ png_read_image(png_ptr, row_pointers);
+
+ // send image to red, green and blue buffers
+ switch (color_type) {
+ case PNG_COLOR_TYPE_GRAY:
+ {
+ unsigned char pixel = 0;
+ for (int y = 0; y < _height; y++) for (int x = 0; x < _width; x++) {
+ pixel = row_pointers[y][x];
+ _bit_plans[RED][y][x] = pixel;
+ _bit_plans[GREEN][y][x] = pixel;
+ _bit_plans[BLUE][y][x] = pixel;
+ }
+ }
+ break;
+
+ case PNG_COLOR_TYPE_GRAY_ALPHA:
+ cerr << "PNG type GRAY_ALPHA not supported.\n";
+ exit(1);
+ break;
+
+ case PNG_COLOR_TYPE_PALETTE:
+ cerr << "PNG type PALETTE not supported.\n";
+ exit(1);
+ break;
+
+ case PNG_COLOR_TYPE_RGB:
+ {
+ if(channels != RGB_DEPTH) {
+ cerr << "Unsupported number of channels for RGB type\n";
+ break;
+ }
+ int k;
+ for (int y = 0; y < _height; y++) {
+ k = 0;
+ for (int x = 0; x < _width; x++) {
+ _bit_plans[RED][y][x] = row_pointers[y][k++];
+ _bit_plans[GREEN][y][x] = row_pointers[y][k++];
+ _bit_plans[BLUE][y][x] = row_pointers[y][k++];
+ }
+ }
+ }
+ break;
+
+ case PNG_COLOR_TYPE_RGB_ALPHA:
+ cerr << "PNG type RGB_ALPHA not supported.\n";
+ exit(1);
+ break;
+
+ default:
+ cerr << "Unknown PNG type\n";
+ exit(1);
+ }
+
+ // release memory
+ png_destroy_read_struct(&png_ptr, &info_ptr, 0);
+
+ for (int y = 0; y < _height; y++) free(row_pointers[y]);
+ free(row_pointers);
+
+ fclose(fp);
+}
+
+void RGBImage::write_png(const char *filename) {
+ png_bytep *row_pointers;
+
+ // create file
+ FILE *fp = fopen(filename, "wb");
+
+ if (!fp) {
+ cerr << "Unable to create image '" << filename << "'\n";
+ exit(1);
+ }
+
+ png_structp png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, 0, 0, 0);
+
+ if (!png_ptr) {
+ cerr << "png_create_write_struct failed\n";
+ fclose(fp);
+ exit(1);
+ }
+
+ png_infop info_ptr = png_create_info_struct(png_ptr);
+ if (!info_ptr) {
+ cerr << "png_create_info_struct failed\n";
+ fclose(fp);
+ exit(1);
+ }
+
+ png_init_io(png_ptr, fp);
+
+ png_set_IHDR(png_ptr, info_ptr, _width, _height,
+ 8, 2, PNG_INTERLACE_NONE,
+ PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
+
+ png_write_info(png_ptr, info_ptr);
+
+ // allocate memory
+ row_pointers = (png_bytep*) malloc(sizeof(png_bytep) * _height);
+ for (int y = 0; y < _height; y++)
+ row_pointers[y] = (png_byte*) malloc(info_ptr->rowbytes);
+
+ int k;
+ for (int y = 0; y < _height; y++) {
+ k = 0;
+ for (int x = 0; x < _width; x++) {
+ row_pointers[y][k++] = _bit_map[x + _width * (y + _height * RED)];
+ row_pointers[y][k++] = _bit_map[x + _width * (y + _height * GREEN)];
+ row_pointers[y][k++] = _bit_map[x + _width * (y + _height * BLUE)];
+ }
+ }
+
+ png_write_image(png_ptr, row_pointers);
+ png_write_end(png_ptr, 0);
+
+ png_destroy_write_struct(&png_ptr, &info_ptr);
+
+ // cleanup heap allocation
+ for (int y = 0; y < _height; y++) free(row_pointers[y]);
+ free(row_pointers);
+
+ fclose(fp);
+}