2025-11-04 14:43:24 +01:00

134 lines
3.5 KiB
C

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "imageInput.h"
#define FILE_HEADER_STRING "__info2_image_file_format__"
// --------------------------
// Hilfsfunktion: Prüft den Header der Datei
// --------------------------
static int checkFileHeader(FILE *file)
{
char buffer[100] = {0};
size_t headerLen = strlen(FILE_HEADER_STRING);
// Lese Header aus Datei
if (fread(buffer, sizeof(char), headerLen, file) != headerLen)
return 0;
// Prüfe, ob Header korrekt ist
return strcmp(buffer, FILE_HEADER_STRING) == 0;
}
// --------------------------
// Hilfsfunktion: Liest ein einzelnes Bild
// --------------------------
static int readImage(FILE *file, GrayScaleImage *image, unsigned int width, unsigned int height)
{
image->width = width; // Breite setzen
image->height = height; // Höhe setzen
image->buffer = (GrayScalePixelType *)malloc(width * height * sizeof(GrayScalePixelType));
if (!image->buffer)
return 0; // Speicherfehler
// Lese Pixelwerte
if (fread(image->buffer, sizeof(GrayScalePixelType), width * height, file) != width * height)
{
free(image->buffer);
image->buffer = NULL;
return 0; // Lese Fehler
}
return 1; // Erfolg
}
// --------------------------
// Funktion: Liest eine Serie von Bildern aus einer Datei
// --------------------------
GrayScaleImageSeries *readImages(const char *path)
{
FILE *file = fopen(path, "rb");
if (!file)
return NULL; // Datei existiert nicht
// Prüfe Header
if (!checkFileHeader(file))
{
fclose(file);
return NULL; // Falsches Format
}
// Lese Anzahl der Bilder und deren Dimensionen
unsigned int count = 0;
unsigned short width = 0, height = 0;
if (fread(&count, sizeof(unsigned int), 1, file) != 1 ||
fread(&width, sizeof(unsigned short), 1, file) != 1 ||
fread(&height, sizeof(unsigned short), 1, file) != 1)
{
fclose(file);
return NULL;
}
// Speicher für Serie allozieren
GrayScaleImageSeries *series = (GrayScaleImageSeries *)malloc(sizeof(GrayScaleImageSeries));
if (!series)
{
fclose(file);
return NULL;
}
series->count = count;
series->images = (GrayScaleImage *)calloc(count, sizeof(GrayScaleImage));
series->labels = (unsigned char *)calloc(count, sizeof(unsigned char));
if (!series->images || !series->labels)
{
clearSeries(series);
fclose(file);
return NULL;
}
// Lese jedes Bild und Label
for (unsigned int i = 0; i < count; i++)
{
if (!readImage(file, &series->images[i], width, height) ||
fread(&series->labels[i], sizeof(unsigned char), 1, file) != 1)
{
clearSeries(series);
fclose(file);
return NULL;
}
}
fclose(file);
return series;
}
// --------------------------
// Funktion: Gibt eine Bildserie vollständig frei
// --------------------------
void clearSeries(GrayScaleImageSeries *series)
{
if (!series)
return;
if (series->images)
{
for (unsigned int i = 0; i < series->count; i++)
{
free(series->images[i].buffer); // Speicher jedes Bildes freigeben
series->images[i].buffer = NULL;
series->images[i].width = 0;
series->images[i].height = 0;
}
free(series->images); // Array der Bilder freigeben
}
if (series->labels)
free(series->labels); // Labels freigeben
free(series); // Serie selbst freigeben
}