YM2HEX

using System;
using System.Text;
using System.Windows.Forms;
using System.IO;

namespace YMextractor
{
    public partial class Form1 : Form
    {
        OpenFileDialog InputFile = new OpenFileDialog();

        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            InputFile.RestoreDirectory  = true;
            InputFile.Filter = "YM-Dateien (*.YM)|*.YM";
            InputFile.ShowDialog();

            if (File.Exists(InputFile.FileName.ToString()))
            {
                FileNameBox.Text = InputFile.FileName.ToString();
                button2.Enabled = true;
            }
            else
            {
                button2.Enabled = false;
            }
        }

        private void button2_Click(object sender, EventArgs e)
        {
            Extractor.Extract(InputFile.FileName.ToString());
            MessageBox.Show("Done");
        }
    }

    public partial class Extractor
    {
        public static void Extract(string filename)
        {
            BinaryReader br = new BinaryReader(File.Open(filename, FileMode.Open));
            BinaryWriter bw = new BinaryWriter(File.Open(filename.Remove(filename.LastIndexOf('.')) + ".hex", FileMode.Create));

            string tempString;
            uint tempInt;       //4 bytes
            ushort tempShort;   //2 bytes

            int frameCount;
            int loopFrame;

            //Header
            ASCIIEncoding encoding = new ASCIIEncoding();

            tempString = encoding.GetString(br.ReadBytes(4));       //Type
            tempString = encoding.GetString(br.ReadBytes(8));       //Check string
            frameCount = (int)SwapByteOrder(br.ReadUInt32());       //Frame count
            tempInt = SwapByteOrder(br.ReadUInt32());               //Song attributes
            tempShort = SwapByteOrder(br.ReadUInt16());             //Digidrums samples
            tempInt = SwapByteOrder(br.ReadUInt32());               //YM Frequency
            tempShort = SwapByteOrder(br.ReadUInt16());             //Frame rate
            loopFrame = (int)SwapByteOrder(br.ReadUInt32());        //Loop Frame Number
            br.ReadUInt16();                                        //Unused bytes

            //Song Info
            tempString = ReadNullTerminationString(br, encoding);   //Title
            tempString = ReadNullTerminationString(br, encoding);   //Artist
            tempString = ReadNullTerminationString(br, encoding);   //Comments

            //Read interleaved frames
            byte[] output = ReadAllFrames(br, frameCount);
            byte[] outputByte = new byte[1];

            br.Close();

            //Stream frames
            for(int i = 0; i < frameCount; i++)
            {
                for(int j = 0; j < 16; j++)
                {
                    outputByte[0] = output[i * 16 + j];
                    bw.Write(outputByte);
                }

                TimeSpan ts = TimeSpan.FromSeconds(((i + 1) / 50));

                //infinite loop
                if(i == (frameCount - 1)) {}
            }

            //mute YM2149
            for(int j = 0; j < 16; j++)
            {
                outputByte[0] = 0;
                bw.Write(outputByte);
            }

            bw.Close();
        }

        public static byte[] ReadAllFrames(BinaryReader reader, int frameCount)
        {
            int totalBytes = 16 * frameCount;
            int currentRegisterStreamSize = totalBytes / 16;

            byte[] tempArray = new byte[totalBytes];
            byte[] finalArray = new byte[totalBytes];

            tempArray = reader.ReadBytes(totalBytes);

            byte currentValue;

            for(int currentRegister = 0; currentRegister < 16; currentRegister++)
            {
                int offset = (currentRegisterStreamSize * (currentRegister));
                for(int i = 0; i < currentRegisterStreamSize; i++)
                {
                    currentValue = tempArray[i + offset];
                    finalArray[16 * i + currentRegister] = currentValue;
                }
            }
            return finalArray;
        }

        public static string ReadNullTerminationString(BinaryReader reader, Encoding encoding)
        {
            byte[] temp = new byte[1];
            StringBuilder sb = new StringBuilder();

            while(true)
            {
                temp[0] = reader.ReadByte();

                if(temp[0] == 0x00) return sb.ToString();
                else sb.Append(encoding.GetString(temp));
            }
        }

        public static uint SwapByteOrder(uint valueToSwap)
        {
            uint uvalue = valueToSwap;
            uint swapped =
                ((0x000000FF) & (uvalue >> 24)
              | (0x0000FF00) & (uvalue >> 8)
              | (0x00FF0000) & (uvalue << 8)
              | (0xFF000000) & (uvalue << 24));
            return swapped;
        }

        public static ushort SwapByteOrder(ushort valueToSwap)
        {
            var uvalue = valueToSwap;
            var swapped =
                ((0x00FF) & (uvalue >> 8)
              | (0xFF00) & (uvalue << 8));
            return (ushort)swapped;
        }
    }
}