Added audio analysis code into preprocessing

audio_preprocessing.ipynb

@@ -12,6 +12,37 @@
     "import librosa\n",
     "import librosa.display"
    ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "import struct\n",
+    "\n",
+    "class WavFileHelper():\n",
+    "    \n",
+    "    def read_file_properties(self, filename):\n",
+    "\n",
+    "        wave_file = open(filename,\"rb\")\n",
+    "        \n",
+    "        riff = wave_file.read(12)\n",
+    "        fmt = wave_file.read(36)\n",
+    "        \n",
+    "        num_channels_string = fmt[10:12]\n",
+    "        num_channels = struct.unpack('<H', num_channels_string)[0]\n",
+    "\n",
+    "        sample_rate_string = fmt[12:16]\n",
+    "        sample_rate = struct.unpack(\"<I\",sample_rate_string)[0]\n",
+    "        \n",
+    "        bit_depth_string = fmt[22:24]\n",
+    "        bit_depth = struct.unpack(\"<H\",bit_depth_string)[0]\n",
+    "\n",
+    "        return (num_channels, sample_rate, bit_depth)\n",
+    "\n",
+    "wavfilehelper = WavFileHelper()"
+   ]
   }
  ],
  "metadata": {