print_file_hex only print non-white pixels

cubesatsim/cubesatsim.ino

@@ -4478,9 +4478,12 @@ void print_file_hex(char* filename, int bytes) {
   File myFile = LittleFS.open(filename, "r"); 
   while (count < bytes) {
     myFile.readBytes(buff, 3);
-    print_hex2(buff[0]);
-    print_hex2(buff[1]);
-    print_hex2(buff[2]);
+ //   print_hex2(buff[0]);
+ //   print_hex2(buff[1]);
+ //   print_hex2(buff[2]);
+	  
+          if ((buff[0]!=0xff) || (buff[1]!=0xff) || (buff[2]!=0xff))
+            Serial.printf("3Non white pixel at %d, %d R: %d G: %d B: %d\n", line, i, buff[0], buff[1],buff[2]);	  
     count += 3;	  
   }
   Serial.println(" ");