132 lines
4.0 KiB
C

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "imageInput.h"
#define BUFFER_SIZE 100
#define FILE_HEADER_STRING "__info2_image_file_format__"
int checkString (FILE *file){ //Checks if String at the start of File equals expected Format (0 for wrong 1 for right)
if (file == NULL){ //returns 0 for empty file
return 0;
}
char expectedString[] = FILE_HEADER_STRING;
char actualString[BUFFER_SIZE];
rewind(file);
size_t bytesRead = fread(actualString, 1,27 , file); //Stores Bytes of start of File to actualString
if (bytesRead != 27){
return 0;
} //Returns 0 if File is to short
actualString[27] = '\0';
if (strcmp(actualString, expectedString) != 0){
return 0;
}
else{
return 1;
}
}
static void setParameters(FILE* file, unsigned int* imageCount, unsigned int* width, unsigned int* height);
static int allocateMemory(GrayScaleImageSeries *series, const int imageCount, const int width, const int height);
GrayScaleImageSeries *readImages(const char *path)
{
FILE* file = fopen(path, "rb");
if(!(checkString(file))){
fclose(file);
return NULL;
}
unsigned int width, height; //uninitialised Variables, will be set by setparamters
GrayScaleImageSeries *series = malloc(sizeof(GrayScaleImageSeries)); //Reserving memory for series
setParameters(file, &(series->count), &width, &height); //setting parameters taken from image file
if(!allocateMemory(series, series->count, width, height)){
clearSeries(series); //If Memory couldnt be correctly allocated a clearing is necessary
fclose(file);
return NULL;
}
//Getting image data
for(unsigned int i = 0; i < series->count ; i++){ //Iterating for every image
for(unsigned int j = 0; j < width * height; j++){ //Iterating for every pixel
fread(&(series->images[i].buffer[j]), sizeof(GrayScalePixelType), 1, file);
}
fread(&(series->labels[i]), sizeof(unsigned char), 1, file); // TODO Added writing in labels array
}
fclose(file);
return series;
}
void clearSeries(GrayScaleImageSeries *series)
{
if (!series)
return;
//Freeing Pixelbuffer for every image
for(unsigned int i = 0; i < series->count; i++)
{
free(series->images[i].buffer);
}
free(series->images); //Freeing Images array
free(series->labels); //Freeing Labels
free(series); //Freeing Main Structure
}
static void setParameters(FILE* file, unsigned int* imageCount, unsigned int* width, unsigned int* height) { // sets the parameters
unsigned short buffer[3];
fseek(file, 27, SEEK_SET);
if(fread(buffer, sizeof(unsigned short), 3, file) != 3){ // TODO changed some stuff here, used UNSIGNED SHORT instead of UNSIGNED CHAR!!
*imageCount = 0;
*width = 0;
*height = 0;
return;
} //Stops if file is too short and clean up
*imageCount = (unsigned int) buffer[0];
*width = (unsigned int) buffer[1];
*height = (unsigned int) buffer[2];
}
static int allocateMemory(GrayScaleImageSeries *series, const int imageCount, const int width, const int height) {
series->count = imageCount; //counts number of images in series
series->images = malloc (sizeof(GrayScaleImage) * imageCount); //Reserving Memory for Images Array
if (series->images == NULL)
return 0;
series->labels = malloc (series->count * sizeof(unsigned char)); //One Label for every Image
if (series->labels == NULL){
return 0;}
for (int i = 0; i < imageCount; i++) { //Reserving Memory for every Images Pixelbuffer and setting width and height
series->images[i].width = width;
series->images[i].height = height;
series->images[i].buffer = malloc(width * height * sizeof(unsigned char)); // allocates memory for every image in the series
if (series->images[i].buffer == NULL){
for (int j = 0; j < i; j++){
free(series->images[j].buffer);
}
free(series->images);
free(series->labels);
return 0;
}
}
return 1;
}