NeuronalesNetz/imageInput.c

129 lines
3.4 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__"
static void strip_newline(char *s)
{
if (!s) return;
size_t len = strlen(s);
while (len > 0 && (s[len-1] == '\n' || s[len-1] == '\r')) {
s[len-1] = '\0';
len--;
}
}
// TODO Implementieren Sie geeignete Hilfsfunktionen für das Lesen der Bildserie aus einer Datei
// TODO Vervollständigen Sie die Funktion readImages unter Benutzung Ihrer Hilfsfunktionen
GrayScaleImageSeries *readImages(const char *path)
{
if (!path) return NULL;
FILE *fp = fopen(path, "r");
if (!fp) return NULL;
char header[BUFFER_SIZE];
if (!fgets(header, sizeof(header), fp)) {
fclose(fp);
return NULL;
}
strip_newline(header);
if (strcmp(header, FILE_HEADER_STRING) != 0) {
fclose(fp);
return NULL;
}
unsigned int count = 0;
if (fscanf(fp, "%u", &count) != 1) {
fclose(fp);
return NULL;
}
GrayScaleImageSeries *series = malloc(sizeof(GrayScaleImageSeries));
if (!series) {
fclose(fp);
return NULL;
}
series->count = count;
series->images = NULL;
series->labels = NULL;
if (count == 0) {
series->images = NULL;
series->labels = NULL;
fclose(fp);
return series;
}
series->images = calloc(count, sizeof(GrayScaleImage));
series->labels = calloc(count, sizeof(unsigned char));
if (!series->images || !series->labels) {
clearSeries(series);
fclose(fp);
return NULL;
}
for (unsigned int i = 0; i < count; ++i) {
unsigned int label = 0;
unsigned int width = 0, height = 0;
if (fscanf(fp, "%u %u %u", &label, &width, &height) != 3) {
clearSeries(series);
fclose(fp);
return NULL;
}
series->labels[i] = (unsigned char)(label & 0xFF);
series->images[i].width = width;
series->images[i].height = height;
size_t pixels = (size_t)width * (size_t)height;
if (pixels == 0) {
series->images[i].buffer = NULL;
continue;
}
series->images[i].buffer = malloc(pixels * sizeof(GrayScalePixelType));
if (!series->images[i].buffer) {
clearSeries(series);
fclose(fp);
return NULL;
}
for (size_t p = 0; p < pixels; ++p) {
int pix = 0;
if (fscanf(fp, "%d", &pix) != 1) {
clearSeries(series);
fclose(fp);
return NULL;
}
if (pix < 0) pix = 0;
if (pix > 255) pix = 255;
series->images[i].buffer[p] = (GrayScalePixelType)pix;
}
}
fclose(fp);
return series;
}
// TODO Vervollständigen Sie die Funktion clearSeries, welche eine Bildserie vollständig aus dem Speicher freigibt
void clearSeries(GrayScaleImageSeries *series)
{
if (!series) return;
if (series->images) {
for (unsigned int i = 0; i < series->count; ++i) {
free(series->images[i].buffer);
series->images[i].buffer = NULL;
}
free(series->images);
series->images = NULL;
}
if (series->labels) {
free(series->labels);
series->labels = NULL;
}
free(series);
}