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MP3 reader

 Saturday, April 06, 2013 published by Exercises C#
Proposed exercise

Create a program to read and display the information stored in a MP3 file (with a "TAG ID3 V1" header): title, artist, album, year.

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ID3 specifications apply to any file or audiovisual container. However, it is usually applied primarily audio containers. There are three versions of the specification that are compatible. For example, a file may contain labels simultaneously version 1.1 and version 2.0. In this case, the media player must decide which are relevant.

ID3 version 1
This first specification is very simple. It consists of attaching a fixed block size of 128 bytes at the end of the file in question. This block contains the following tags:
A header that identifies the presence of block ID3 and version. Specifically, said header comprises TAG characters.
Title: 30 characters.
Artist: 30 characters.
Album: 30 characters.
Year: 4 characters.
Comment: 30 characters.
Genre (music): a character.
All tags using ASCII characters except gender, an integer stored within a single byte. The musical genre associated with each byte is predefined in the standard definitions and includes 80 genera, numbered 0 to 79. Some breeding programs have expanded their own defined genres (from 80th).


Output



Solution


using System;
using System.IO;

public class MP3Reader
{
public static void Main()
{
const int SIZE = 128;

byte[] data;
int width, height;

Console.Write("Enter name: ");
string name = Console.ReadLine();

if(!File.Exists(name))
{
Console.WriteLine("Not exists");
return;
}

try
{
FileStream file = File.OpenRead(name);
data = new byte[SIZE];

file.Seek(-128, SeekOrigin.End);
file.Read(data, 0, SIZE);

file.Close();

byte b1 = data[0];
byte b2 = data[1];
byte b3 = data[2];

if( Convert.ToChar(b1) != 'T' || Convert.ToChar(b2) != 'A' || 
Convert.ToChar(b3) != 'G')
{
Console.WriteLine("not mp3 valid");
return;
}

int i = 3;

string title = "";
for (; i < 33; i++)
{
if (data[i] != 0)
title += Convert.ToChar(data[i]);
}

string author = "";
for (i = 33; i < 63; i++)
{
if (data[i] != 0)
author += Convert.ToChar(data[i]);
}

string album = "";
for (i = 63; i < 93; i++)
{
if (data[i] != 0)
album += Convert.ToChar(data[i]);
}

string year = "";
for (i = 93; i < 97; i++)
{
if (data[i] != 0)
year += Convert.ToChar(data[i]);
}

string comments = "";
for (i = 97; i < 127; i++)
{
if (data[i] != 0)
comments += Convert.ToChar(data[i]);
}

Console.WriteLine("Data of MP3:");
Console.WriteLine("----------------------------");
Console.WriteLine();

Console.WriteLine("Title: " + title);
Console.WriteLine("Author: " + author);
Console.WriteLine("Album: " + album);
Console.WriteLine("Year: " + year);
Console.WriteLine("Comments: " + comments);
Console.WriteLine("Genre: " + data[127] );
}
catch(Exception)
{
Console.WriteLine("Error");
}
}
}