NeuronalesNetz/imageInput.c

105 lines
2.8 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__"
// TODO Implementieren Sie geeignete Hilfsfunktionen für das Lesen der Bildserie aus einer Datei
//Hilfsfunktion Header prüfen
static int checkHeader(FILE *file) {
char buffer[100];
if (fgets(buffer, sizeof(buffer), file) == NULL)
return 0;
buffer[strcspn(buffer, "\r\n")] = 0;
return strcmp(buffer,FILE_HEADER_STRING ) == 0;
}
//Hilfsfkt. 2 Bytes als unsigned short lesen (littel Endian)
static unsigned short readUShort(FILE *file) {
unsigned char bytes[2];
fread(bytes, 1, 2, file);
return (bytes[1] << 8) | bytes[0]; // Little Endian
}
// TODO Vervollständigen Sie die Funktion readImages unter Benutzung Ihrer Hilfsfunktionen
GrayScaleImageSeries *readImages(const char *path)
{
FILE *file = fopen(path, "rb");
if (!file) return NULL;
if (!checkHeader(file)) {
fclose(file);
return NULL;
}
unsigned short count = readUShort(file);
unsigned short width = readUShort(file);
unsigned short height = readUShort(file);
if (count == 0 || width == 0 || height == 0) {
fclose(file);
return NULL;
}
GrayScaleImageSeries *series = malloc(sizeof(GrayScaleImageSeries));
if (!series) { fclose(file); return NULL; }
series->count = count;
series->labels = malloc(count * sizeof(unsigned char));
series->images = malloc(count * sizeof(GrayScaleImage));
if (!series->labels || !series->images) {
fclose(file);
free(series->labels);
free(series->images);
free(series);
return NULL;
}
for (unsigned int i = 0; i < count; i++) {
GrayScaleImage *img = &series->images[i];
img->width = width;
img->height = height;
img->buffer = malloc(width * height * sizeof(GrayScalePixelType));
if (!img->buffer) {
fclose(file);
clearSeries(series);
return NULL;
}
if (fread(img->buffer, sizeof(GrayScalePixelType), width * height, file) != width * height) {
fclose(file);
clearSeries(series);
return NULL;
}
if (fread(&series->labels[i], sizeof(unsigned char), 1, file) != 1) {
fclose(file);
clearSeries(series);
return NULL;
}
}
fclose(file);
return series;
}
// TODO Vervollständigen Sie die Funktion clearSeries, welche eine Bildserie vollständig aus dem Speicher freigibt
void clearSeries(GrayScaleImageSeries *series)
{
if (!series) return;
for (unsigned int i = 0; i < series->count; i++) {
free(series->images[i].buffer);
}
free(series->images);
free(series->labels);
free(series);
}