protected virtual unsafe short[] EndFrame()
{
NesApu.EndFrame(apuIndex);
int numTotalSamples = NesApu.SamplesAvailable(apuIndex);
short[] samples = new short[numTotalSamples];
fixed(short *ptr = &samples[0])
{
NesApu.ReadSamples(apuIndex, new IntPtr(ptr), numTotalSamples);
}
return(samples);
}
public unsafe static void Save(Song song, string filename, int sampleRate)
{
var advance = true;
var tempoCounter = 0;
var playPattern = 0;
var playNote = 0;
var jumpPattern = -1;
var jumpNote = -1;
var speed = song.Speed;
var wavBytes = new List <byte>();
var apuIndex = NesApu.APU_WAV_EXPORT;
var dmcCallback = new NesApu.DmcReadDelegate(NesApu.DmcReadCallback);
var dmcCallbackHandle = GCHandle.Alloc(dmcCallback); // Needed since callback can be collected.
var channels = PlayerBase.CreateChannelStates(song.Project, apuIndex);
NesApu.InitAndReset(apuIndex, sampleRate, PlayerBase.GetNesApuExpansionAudio(song.Project), dmcCallback);
for (int i = 0; i < channels.Length; i++)
{
NesApu.EnableChannel(apuIndex, i, 1);
}
while (true)
{
// Advance to next note.
if (advance)
{
foreach (var channel in channels)
{
channel.ProcessEffects(song, playPattern, playNote, ref jumpPattern, ref jumpNote, ref speed, false);
}
foreach (var channel in channels)
{
channel.Advance(song, playPattern, playNote);
}
advance = false;
}
// Update envelopes + APU registers.
foreach (var channel in channels)
{
channel.UpdateEnvelopes();
channel.UpdateAPU();
}
NesApu.EndFrame(apuIndex);
int numTotalSamples = NesApu.SamplesAvailable(apuIndex);
byte[] samples = new byte[numTotalSamples * 2];
fixed(byte *ptr = &samples[0])
{
NesApu.ReadSamples(apuIndex, new IntPtr(ptr), numTotalSamples);
}
wavBytes.AddRange(samples);
if (!PlayerBase.AdvanceTempo(song, speed, LoopMode.None, ref tempoCounter, ref playPattern, ref playNote, ref jumpPattern, ref jumpNote, ref advance))
{
break;
}
}
using (var file = new FileStream(filename, FileMode.Create))
{
var header = new WaveHeader();
// RIFF WAVE Header
header.chunkId[0] = (byte)'R';
header.chunkId[1] = (byte)'I';
header.chunkId[2] = (byte)'F';
header.chunkId[3] = (byte)'F';
header.format[0] = (byte)'W';
header.format[1] = (byte)'A';
header.format[2] = (byte)'V';
header.format[3] = (byte)'E';
// Format subchunk
header.subChunk1Id[0] = (byte)'f';
header.subChunk1Id[1] = (byte)'m';
header.subChunk1Id[2] = (byte)'t';
header.subChunk1Id[3] = (byte)' ';
header.audioFormat = 1; // FOR PCM
header.numChannels = 1; // 1 for MONO, 2 for stereo
header.sampleRate = sampleRate; // ie 44100 hertz, cd quality audio
header.bitsPerSample = 16; //
header.byteRate = header.sampleRate * header.numChannels * header.bitsPerSample / 8;
header.blockAlign = (short)(header.numChannels * header.bitsPerSample / 8);
// Data subchunk
header.subChunk2Id[0] = (byte)'d';
header.subChunk2Id[1] = (byte)'a';
header.subChunk2Id[2] = (byte)'t';
header.subChunk2Id[3] = (byte)'a';
// All sizes for later:
// chuckSize = 4 + (8 + subChunk1Size) + (8 + subChubk2Size)
// subChunk1Size is constanst, i'm using 16 and staying with PCM
// subChunk2Size = nSamples * nChannels * bitsPerSample/8
// Whenever a sample is added:
// chunkSize += (nChannels * bitsPerSample/8)
// subChunk2Size += (nChannels * bitsPerSample/8)
header.subChunk1Size = 16;
header.subChunk2Size = wavBytes.Count;
header.chunkSize = 4 + (8 + header.subChunk1Size) + (8 + header.subChunk2Size);
var headerBytes = new byte[sizeof(WaveHeader)];
Marshal.Copy(new IntPtr(&header), headerBytes, 0, headerBytes.Length);
file.Write(headerBytes, 0, headerBytes.Length);
file.Write(wavBytes.ToArray(), 0, wavBytes.Count);
}
dmcCallbackHandle.Free();
}