Funktion aufgeteilt

imageInput.c

@@ -43,106 +43,166 @@ static int checkHeader(const GrayScalePixelType *buffer){
 
 }
 
+static FILE *openImageFile(const char *path)
+{
+    return fopen(path, "rb");
+}
+
+static int readHeaderFromFile(FILE *fp, GrayScalePixelType *headerBuffer)
+{
+    if (fread(headerBuffer, sizeof(GrayScalePixelType),HEADER_LEN, fp) != HEADER_LEN)
+    {
+        return 0;
+    }
+    return 1;
+}
+
+static int readMetaData(FILE *fp, unsigned int *numImages, unsigned int *width, unsigned int *height)
+{
+    if (fread(numImages, sizeof(unsigned int), 1, fp) != 1 || fread(width, sizeof(unsigned int), 1, fp) != 1 || fread(height, sizeof(unsigned int), 1, fp) != 1)
+
+    {
+    return 0;
+    }
+    return 1;
+}
+
+static GrayScaleImageSeries *allocateSeriesStruct(void)
+{
+    GrayScaleImageSeries *series = malloc(sizeof(GrayScaleImageSeries));
+    return series;
+}
+
+static int allocateImageAndLabelArrays(GrayScaleImageSeries *series, unsigned int numImages, FILE *fp)
+{
+    series->count = numImages;
+    //Speicher für die Pointer an sich belegen
+    series->images = malloc(numImages * sizeof(GrayScaleImage));
+    series->labels = malloc(numImages * sizeof(unsigned char));
+
+    if (!series->images || !series->labels)
+    {
+        free(series->images); //wenn trotzdem was reingeschrieben wurde, dann freigeben
+        free(series->labels);
+        free(series);
+
+        fclose(fp);
+        return 0;
+    }
+
+    return 1;
+}
+
+static int allocateBufferForImages(GrayScaleImageSeries *series, unsigned int numImages, unsigned int width, unsigned int height, FILE *fp)
+{
+    for (unsigned int i = 0; i < numImages; i++)
+    {
+        series ->images[i].buffer = malloc(width * height);
+        if (series ->images[i].buffer == NULL) 
+        {
+            for (unsigned int j = 0; j < i; j++)
+            {
+                free(series->images[j].buffer);
+            }
+
+            free(series->images);
+            free(series->labels);
+            free(series);
+
+            fclose(fp);
+            return 0;
+        }
+    }
+    return 1;
+}
+
+static int readImagesAndLabels(FILE *fp, GrayScaleImageSeries *series, unsigned int numImages, unsigned int width, unsigned int height)
+{
+    for (unsigned int i = 0; i < numImages; i++)
+    {
+        series->images[i].width = width;
+        series->images[i].height = height;
+
+        if (fread(series->images[i].buffer, 1, width *height, fp) != (width * height))
+        {
+            clearSeries(series);
+            fclose(fp);
+            return 0;
+        }
+
+        fread(&series->labels[i], 1, 1, fp);
+    }
+
+    return 1;
+}
+
+
 // TODO Vervollständigen Sie die Funktion readImages unter Benutzung Ihrer Hilfsfunktionen
 GrayScaleImageSeries *readImages(const char *path)
 {
     GrayScaleImageSeries *series = NULL;
 
-    FILE *fp = fopen(path, "rb"); //Datei im Binärmodus öffnen
+    FILE *fp = openImageFile(path);
-    if(!fp)
+    if (!fp)
-        return NULL; //Fehler: Datei konnte nicht geöffnet werden 
+    return NULL;
 
-    //Buffer zum Einlesen des Headers 
     GrayScalePixelType header[HEADER_LEN];
 
-    //Prüfen, ob genau die HEADER_LEN Bytes eingelesen werden
+    if (!readHeaderFromFile(fp, header))
-    if(fread(header, sizeof(GrayScalePixelType), HEADER_LEN, fp) != HEADER_LEN){
-        fclose(fp);
-        return NULL;
-    }
-
-    //Prüfen, ob es sich um den korrekten Header handelt mit Hilfsfunktion
-    if(!checkHeader(header)){
-        fclose(fp);
-        return NULL;
-    }
-
-    //Anzahl der Bilder, Breite und Höhe einlesen 
-    unsigned  int numImages, width, height;
-    if(fread(&numImages, sizeof(unsigned int), 1, fp) != 1 || fread(&width, sizeof(unsigned int), 1, fp) != 1 || fread(&height, sizeof(unsigned int), 1, fp)!= 1)
     {
         fclose(fp);
         return NULL;
     }
 
+    if (!checkHeader(header))
+    {
+        fclose(fp);
+        return NULL;
+    }
+
+    unsigned int numImages, width, height;
+    if (!readMetaData(fp, &numImages, &width, &height))
+    {
+        fclos(fp);
+        return NULL;
+    }
+
     if (!checkDimensions(width, height))
     {
         fclose(fp);
         return NULL;
     }
 
-    //Speicher für die gesamte Bildserie reservieren (aber nur für die Pointer und das count-Feld)
+    series = allocateSeriesStruct();
-    series = malloc(sizeof(GrayScaleImageSeries));
+    if (!series)
-    if(!series) {
+    {
         free(series);
-        fclose(fp);
-        return NULL; //Fehler bei Speicherreservierung 
-    }
-
-    series->count = numImages;
-    //Speicher für die Pointer an sich belegen
-    series->images = malloc(numImages * sizeof(GrayScaleImage));
-    series->labels = malloc(numImages * sizeof(unsigned char));
-
-    //Prüfen, ob der Speicher reserviert werden konnte
-    for(unsigned int i = 0; i < numImages; i++){
-
-        series -> images[i].buffer = malloc(width * height);
-
-        if(series->images[i].buffer == NULL){
-
-            for(unsigned int j = 0; j < i; j++){
-                free(series->images[j].buffer);
-            }
-
-        
-        free(series->images); //wenn trotzdem was reingeschrieben wurde, dann freigeben
-        free(series->labels);
-        free(series);
-
         fclose(fp);
         return NULL;
-
-        
-        }
     }
 
-   for(int i = 0; i < numImages; i++)
+    if (!allocateImageAndLabelArrays(series, numImages, fp))
-   {
+    {
-        
+        return NULL;
-        series -> images[i].width = width;
-        series -> images[i].height = height;
-
-
-        if(fread(series -> images[i].buffer, 1, width * height, fp) != (width * height))
-        {
-            clearSeries(series);
-            fclose(fp);
-            return NULL;
-        }
-
-        fread(&series -> labels[i], 1, 1, fp);
     }
 
+    if (!allocateImageAndLabelImages(series, numImages, width, height, fp))
+    {
+        return NULL;
+    }
 
-
+    if (!readImagesAndLabels(fp, series, numImages, width, height))
-    
+    {
-    
+        return NULL;
+    }
 
     return series;
+
 }   
 
+
 // TODO Vervollständigen Sie die Funktion clearSeries, welche eine Bildserie vollständig aus dem Speicher freigibt
 void clearSeries(GrayScaleImageSeries *series)
 {
+
 }