BizHawk/BizHawk.Emulation.Common/Sound/Utilities/ISynchronizingAudioBuffer.cs

653 lines
18 KiB
C#

using System;
using System.Collections.Generic;
namespace BizHawk.Emulation.Common
{
public interface ISynchronizingAudioBuffer
{
void EnqueueSamples(short[] buf, int samplesProvided);
void EnqueueSample(short left, short right);
void Clear();
// returns the number of samples actually supplied, which may not match the number requested
// ^^ what the hell is that supposed to mean.
// the entire point of an ISynchronzingAudioBuffer
// is to provide exact amounts of output samples,
// even when the input provided varies....
int OutputSamples(short[] buf, int samplesRequested);
}
internal class ZeromusSynchronizer : ISynchronizingAudioBuffer
{
public ZeromusSynchronizer()
{
////#ifdef NDEBUG
_adjustobuf = new Adjustobuf(200, 1000);
////#else
////adjustobuf = new Adjustobuf(22000, 44000);
////#endif
}
// adjustobuf(200,1000)
private bool _mixqueueGo;
public void Clear()
{
_adjustobuf.Clear();
}
public void EnqueueSample(short left, short right)
{
_adjustobuf.Enqueue(left, right);
}
public void EnqueueSamples(short[] buf, int samplesProvided)
{
int ctr = 0;
for (int i = 0; i < samplesProvided; i++)
{
short left = buf[ctr++];
short right = buf[ctr++];
_adjustobuf.Enqueue(left, right);
}
}
// returns the number of samples actually supplied, which may not match the number requested
public int OutputSamples(short[] buf, int samplesRequested)
{
int ctr = 0;
int done = 0;
if (!_mixqueueGo)
{
if (_adjustobuf.Size > 200)
{
_mixqueueGo = true;
}
}
else
{
for (int i = 0; i < samplesRequested; i++)
{
if (_adjustobuf.Size == 0)
{
_mixqueueGo = false;
break;
}
done++;
short left, right;
_adjustobuf.Dequeue(out left, out right);
buf[ctr++] = left;
buf[ctr++] = right;
}
}
return done;
}
private readonly Adjustobuf _adjustobuf;
private class Adjustobuf
{
public Adjustobuf(int minLatency, int maxLatency)
{
_minLatency = minLatency;
_maxLatency = maxLatency;
Clear();
}
private readonly int _minLatency;
private readonly int _maxLatency;
private readonly short[] _curr = new short[2];
private readonly Queue<short> _buffer = new Queue<short>();
private readonly Queue<int> _statsHistory = new Queue<int>();
private float _rate, _cursor;
private int _targetLatency;
private long _rollingTotalSize;
private uint _kAverageSize;
public int Size { get; private set; }
public void Clear()
{
_buffer.Clear();
_statsHistory.Clear();
_rollingTotalSize = 0;
_targetLatency = (_maxLatency + _minLatency) / 2;
_rate = 1.0f;
_cursor = 0.0f;
_curr[0] = _curr[1] = 0;
_kAverageSize = 80000;
Size = 0;
}
public void Enqueue(short left, short right)
{
_buffer.Enqueue(left);
_buffer.Enqueue(right);
Size++;
}
private void AddStatistic()
{
_statsHistory.Enqueue(Size);
_rollingTotalSize += Size;
if (_statsHistory.Count > _kAverageSize)
{
_rollingTotalSize -= _statsHistory.Peek();
_statsHistory.Dequeue();
float averageSize = (float)(_rollingTotalSize / _kAverageSize);
////static int ctr=0; ctr++; if((ctr&127)==0) printf("avg size: %f curr size: %d rate: %f\n",averageSize,size,rate);
{
float targetRate;
if (averageSize < _targetLatency)
{
targetRate = 1.0f - ((_targetLatency - averageSize) / _kAverageSize);
}
else if (averageSize > _targetLatency)
{
targetRate = 1.0f + ((averageSize - _targetLatency) / _kAverageSize);
}
else
{
targetRate = 1.0f;
}
////rate = moveValueTowards(rate,targetRate,0.001f);
_rate = targetRate;
}
}
}
public void Dequeue(out short left, out short right)
{
left = right = 0;
AddStatistic();
if (Size == 0)
{
return;
}
_cursor += _rate;
while (_cursor > 1.0f)
{
_cursor -= 1.0f;
if (Size > 0)
{
_curr[0] = _buffer.Dequeue();
_curr[1] = _buffer.Dequeue();
Size--;
}
}
left = _curr[0];
right = _curr[1];
}
}
}
internal class NitsujaSynchronizer : ISynchronizingAudioBuffer
{
private struct Ssamp
{
public readonly short L, R;
public Ssamp(short left, short right)
{
L = left;
R = right;
}
}
private readonly List<Ssamp> _sampleQueue = new List<Ssamp>();
// returns values going between 0 and y-1 in a saw wave pattern, based on x
private static int Pingpong(int x, int y)
{
x %= 2 * y;
if (x >= y)
{
x = (2 * y) - x - 1;
}
return x;
// in case we want to switch to odd buffer sizes for more sharpness
////x %= 2*(y-1);
////if(x >= y)
////x = 2*(y-1) - x;
////return x;
}
private static Ssamp Crossfade(Ssamp lhs, Ssamp rhs, int cur, int start, int end)
{
if (cur <= start)
{
return lhs;
}
if (cur >= end)
{
return rhs;
}
// in case we want sine wave interpolation instead of linear here
////float ang = 3.14159f * (float)(cur - start) / (float)(end - start);
////cur = start + (int)((1-cosf(ang))*0.5f * (end - start));
int inNum = cur - start;
int outNum = end - cur;
int denom = end - start;
int lrv = ((lhs.L * outNum) + (rhs.L * inNum)) / denom;
int rrv = ((lhs.R * outNum) + (rhs.R * inNum)) / denom;
return new Ssamp((short)lrv, (short)rrv);
}
public void Clear()
{
_sampleQueue.Clear();
}
private static void EmitSample(short[] outbuf, ref int cursor, Ssamp sample)
{
outbuf[cursor++] = sample.L;
outbuf[cursor++] = sample.R;
}
private static void EmitSamples(short[] outbuf, ref int outcursor, Ssamp[] samplebuf, int incursor, int samples)
{
for (int i = 0; i < samples; i++)
{
EmitSample(outbuf, ref outcursor, samplebuf[i + incursor]);
}
}
private static short Abs(short value)
{
if (value < 0)
{
return (short)-value;
}
return value;
}
private static int Abs(int value)
{
if (value < 0)
{
return -value;
}
return value;
}
public void EnqueueSamples(short[] buf, int samplesProvided)
{
int cursor = 0;
for (int i = 0; i < samplesProvided; i++)
{
_sampleQueue.Add(new Ssamp(buf[cursor + 0], buf[cursor + 1]));
cursor += 2;
}
}
public void EnqueueSample(short left, short right)
{
_sampleQueue.Add(new Ssamp(left, right));
}
public int OutputSamples(short[] buf, int samplesRequested)
{
Console.WriteLine("{0} {1}", samplesRequested, _sampleQueue.Count); // add this line
int bufcursor = 0;
int audiosize = samplesRequested;
int queued = _sampleQueue.Count;
// I am too lazy to deal with odd numbers
audiosize &= ~1;
queued &= ~1;
if (queued > 0x200 && audiosize > 0) // is there any work to do?
{
// are we going at normal speed?
// or more precisely, are the input and output queues/buffers of similar size?
if (queued > 900 || audiosize > queued * 2)
{
// not normal speed. we have to resample it somehow in this case.
if (audiosize <= queued)
{
// fast forward speed
// this is the easy case, just crossfade it and it sounds ok
for (int i = 0; i < audiosize; i++)
{
int j = i + queued - audiosize;
Ssamp outsamp = Crossfade(_sampleQueue[i], _sampleQueue[j], i, 0, audiosize);
EmitSample(buf, ref bufcursor, outsamp);
}
}
else
{
// slow motion speed
// here we take a very different approach,
// instead of crossfading it, we select a single sample from the queue
// and make sure that the index we use to select a sample is constantly moving
// and that it starts at the first sample in the queue and ends on the last one.
//
// hopefully the index doesn't move discontinuously or we'll get slight crackling
// (there might still be a minor bug here that causes this occasionally)
//
// here's a diagram of how the index we sample from moves:
//
// queued (this axis represents the index we sample from. the top means the end of the queue)
// ^
// | --> audiosize (this axis represents the output index we write to, right meaning forward in output time/position)
// | A C C end
// A A B C C C
// A A A B C C C
// A A A B C C
// A A C
// start
//
// yes, this means we are spending some stretches of time playing the sound backwards,
// but the stretches are short enough that this doesn't sound weird.
// this lets us avoid most crackling problems due to the endpoints matching up.
// first calculate a shorter-than-full window
// that has minimal slope at the endpoints
// (to further reduce crackling, especially in sine waves)
int beststart = 0, extraAtEnd = 0;
{
int bestend = queued;
const int Worstdiff = 99999999;
int beststartdiff = Worstdiff;
int bestenddiff = Worstdiff;
for (int i = 0; i < 128; i += 2)
{
int diff = Abs(_sampleQueue[i].L - _sampleQueue[i + 1].L) + Abs(_sampleQueue[i].R - _sampleQueue[i + 1].R);
if (diff < beststartdiff)
{
beststartdiff = diff;
beststart = i;
}
}
for (int i = queued - 3; i > queued - 3 - 128; i -= 2)
{
int diff = Abs(_sampleQueue[i].L - _sampleQueue[i + 1].L) + Abs(_sampleQueue[i].R - _sampleQueue[i + 1].R);
if (diff < bestenddiff)
{
bestenddiff = diff;
bestend = i + 1;
}
}
extraAtEnd = queued - bestend;
queued = bestend - beststart;
int oksize = queued;
while (oksize + (queued * 2) + beststart + extraAtEnd <= samplesRequested)
{
oksize += queued * 2;
}
audiosize = oksize;
for (int x = 0; x < beststart; x++)
{
EmitSample(buf, ref bufcursor, _sampleQueue[x]);
}
// sampleQueue.erase(sampleQueue.begin(), sampleQueue.begin() + beststart);
_sampleQueue.RemoveRange(0, beststart); // zero 08-nov-2010: did i do this right?
}
int midpointX = audiosize >> 1;
int midpointY = queued >> 1;
// all we need to do here is calculate the X position of the leftmost "B" in the above diagram.
// TODO: we should calculate it with a simple equation like
// midpointXOffset = min(something,somethingElse);
// but it's a little difficult to work it out exactly
// so here's a stupid search for the value for now:
int prevA = 999999;
int midpointXOffset = queued / 2;
while (true)
{
int a = Abs(Pingpong(midpointX - midpointXOffset, queued) - midpointY) - midpointXOffset;
if (((a > 0) != (prevA > 0) || (a < 0) != (prevA < 0)) && prevA != 999999)
{
if (((a + prevA) & 1) != 0) // there's some sort of off-by-one problem with this search since we're moving diagonally...
{
midpointXOffset++; // but this fixes it most of the time...
}
break; // found it
}
prevA = a;
midpointXOffset--;
if (midpointXOffset < 0)
{
midpointXOffset = 0;
break; // failed to find it. the two sides probably meet exactly in the center.
}
}
int leftMidpointX = midpointX - midpointXOffset;
int rightMidpointX = midpointX + midpointXOffset;
int leftMidpointY = Pingpong(leftMidpointX, queued);
int rightMidpointY = (queued - 1) - Pingpong((int)audiosize - 1 - rightMidpointX + (queued * 2), queued);
// output the left almost-half of the sound (section "A")
for (int x = 0; x < leftMidpointX; x++)
{
int i = Pingpong(x, queued);
EmitSample(buf, ref bufcursor, _sampleQueue[i]);
}
// output the middle stretch (section "B")
int y = leftMidpointY;
int dyMidLeft = (leftMidpointY < midpointY) ? 1 : -1;
int dyMidRight = (rightMidpointY > midpointY) ? 1 : -1;
for (int x = leftMidpointX; x < midpointX; x++, y += dyMidLeft)
{
EmitSample(buf, ref bufcursor, _sampleQueue[y]);
}
for (int x = midpointX; x < rightMidpointX; x++, y += dyMidRight)
{
EmitSample(buf, ref bufcursor, _sampleQueue[y]);
}
// output the end of the queued sound (section "C")
for (int x = rightMidpointX; x < audiosize; x++)
{
int i = (queued - 1) - Pingpong((int)audiosize - 1 - x + (queued * 2), queued);
EmitSample(buf, ref bufcursor, _sampleQueue[i]);
}
for (int x = 0; x < extraAtEnd; x++)
{
int i = queued + x;
EmitSample(buf, ref bufcursor, _sampleQueue[i]);
}
queued += extraAtEnd;
audiosize += beststart + extraAtEnd;
} // end else
// sampleQueue.erase(sampleQueue.begin(), sampleQueue.begin() + queued);
_sampleQueue.RemoveRange(0, queued);
// zero 08-nov-2010: did i do this right?
return audiosize;
}
else
{
// normal speed
// just output the samples straightforwardly.
//
// at almost-full speeds (like 50/60 FPS)
// what will happen is that we rapidly fluctuate between entering this branch
// and entering the "slow motion speed" branch above.
// but that's ok! because all of these branches sound similar enough that we can get away with it.
// so the two cases actually complement each other.
if (audiosize >= queued)
{
EmitSamples(buf, ref bufcursor, _sampleQueue.ToArray(), 0, queued);
// sampleQueue.erase(sampleQueue.begin(), sampleQueue.begin() + queued);
_sampleQueue.RemoveRange(0, queued);
// zero 08-nov-2010: did i do this right?
return queued;
}
else
{
EmitSamples(buf, ref bufcursor, _sampleQueue.ToArray(), 0, audiosize);
// sampleQueue.erase(sampleQueue.begin(), sampleQueue.begin()+audiosize);
_sampleQueue.RemoveRange(0, audiosize);
// zero 08-nov-2010: did i do this right?
return audiosize;
}
} // end normal speed
} // end if there is any work to do
else
{
return 0;
}
} // output_samples
} // NitsujaSynchronizer
internal class VecnaSynchronizer : ISynchronizingAudioBuffer
{
// vecna's attempt at a fully synchronous sound provider.
// It's similar in philosophy to my "BufferedAsync" provider, but BufferedAsync is not
// fully synchronous.
// Like BufferedAsync, it tries to make most frames 100% correct and just suck it up
// periodically and have a big bad-sounding mistake frame if it has to.
// It is significantly less ambitious and elaborate than the other methods.
// We'll see if it works better or not!
// It has a min and maximum amount of excess buffer to deal with minor overflows.
// When fastforwarding, it will discard samples above the maximum excess buffer.
// When underflowing, it will attempt to resample to a certain threshhold.
// If it underflows beyond that threshhold, it will give up and output silence.
// Since it has done this, it will go ahead and generate some excess silence in order
// to restock its excess buffer.
private struct Sample
{
public readonly short Left;
public readonly short Right;
public Sample(short left, short right)
{
Left = left;
Right = right;
}
}
private const int SamplesInOneFrame = 735;
private const int MaxExcessSamples = 2048;
private readonly Queue<Sample> _buffer;
private readonly Sample[] _resampleBuffer;
public VecnaSynchronizer()
{
_buffer = new Queue<Sample>(2048);
_resampleBuffer = new Sample[2730]; // 2048 * 1.25
// Give us a little buffer wiggle-room
for (int i = 0; i < 367; i++)
{
_buffer.Enqueue(new Sample(0, 0));
}
}
public void EnqueueSamples(short[] buf, int samplesProvided)
{
int ctr = 0;
for (int i = 0; i < samplesProvided; i++)
{
short left = buf[ctr++];
short right = buf[ctr++];
EnqueueSample(left, right);
}
}
public void EnqueueSample(short left, short right)
{
if (_buffer.Count >= MaxExcessSamples - 1)
{
// if buffer is overfull, dequeue old samples to make room for new samples.
_buffer.Dequeue();
}
_buffer.Enqueue(new Sample(left, right));
}
public void Clear()
{
_buffer.Clear();
}
public int OutputSamples(short[] buf, int samplesRequested)
{
if (samplesRequested > _buffer.Count)
{
// underflow!
if (_buffer.Count > samplesRequested * 3 / 4)
{
// if we're within 75% of target, then I guess we suck it up and resample.
// we sample in a goofy way, we could probably do it a bit smarter, if we cared more.
int samplesAvailable = _buffer.Count;
for (int i = 0; _buffer.Count > 0; i++)
{
_resampleBuffer[i] = _buffer.Dequeue();
}
int index = 0;
for (int i = 0; i < samplesRequested; i++)
{
Sample sample = _resampleBuffer[i * samplesAvailable / samplesRequested];
buf[index++] += sample.Left;
buf[index++] += sample.Right;
}
}
else
{
// we're outside of a "reasonable" underflow. Give up and output silence.
// Do nothing. The whole frame will be excess buffer.
}
}
else
{
// normal operation
////Console.WriteLine("samples in buffer {0}, requested {1}", buffer.Count, samples_requested);
int index = 0;
for (int i = 0; i < samplesRequested && _buffer.Count > 0; i++)
{
Sample sample = _buffer.Dequeue();
buf[index++] += sample.Left;
buf[index++] += sample.Right;
}
}
return samplesRequested;
}
}
}