/// ------------------------------------------------------------------------------------
public void Seek(long offset, SeekOrigin origin)
{
_reader.Seek(offset, origin);
_sampleChannel = new SampleChannel(_reader);
}
public static void AppendWork(Stream OutputStream, Stream InputStream, double offset, double length,
double ovr, List <KeyValuePair <double, double> > KV, double droptime, uint HeadLength = 0)
{
//Init
WaveFormat outputFormat = new WaveFormat(44100, 1);
FormatHelper fhelper = new FormatHelper(outputFormat);
MathHelper mhelper = new MathHelper();
//IOInit
WaveFileReader ifh = null;
try { ifh = new WaveFileReader(InputStream); }
catch {; }
IOHelper ofh = new IOHelper(OutputStream, outputFormat, HeadLength);
//Prepare
OutputStream.Seek(0, SeekOrigin.End);
int outputFrames = fhelper.Ms2Samples(length);
int overlapFrames = fhelper.Ms2Samples(ovr);
int offsetFrames = fhelper.Ms2Samples(offset);
List <MathHelper.SegmentLine> EnvlopeLines = fhelper.KV2SegmentLines(outputFrames, KV);
//CheckDelay
int dropFrames = fhelper.Ms2Samples(droptime);
if (dropFrames < 0)
{
dropFrames = 0;
}
if (dropFrames > 0)
{
if (dropFrames > outputFrames - overlapFrames)
{
return;
}
}
//SeekInput
if (ifh != null)
{
if (offsetFrames > 0)
{
ifh.Seek(fhelper.Samples2Bytes((uint)offsetFrames), SeekOrigin.Begin);
}
else
{
ifh.Seek(0, SeekOrigin.Begin);
}
}
//SetWritePoint
if (overlapFrames > 0)
{
long seekMap = fhelper.Samples2Bytes((uint)overlapFrames);
if (OutputStream.Length >= seekMap)
{
OutputStream.Seek((-1) * seekMap, SeekOrigin.End);
}
}
else if (overlapFrames < 0)
{
OutputStream.Seek(0, SeekOrigin.End);
for (int i = 0; i < -overlapFrames; i++)
{
if (dropFrames > 0)
{
dropFrames--;
}
else
{
ofh.WriteSample(0.0f);
}
}
overlapFrames = 0;
}
for (int currentFrame = 0; currentFrame < outputFrames; currentFrame++)
{
float[] SampleFrame = new float[1] {
0.0f
};
if (ifh != null && ifh.Position < ifh.Length)
{
SampleFrame = ifh.ReadNextSampleFrame();
if (SampleFrame == null)
{
SampleFrame = new float[1] {
0.0f
};
}
}
float SampleMono = SampleFrame.Length == 1 ? SampleFrame[0] : mhelper.floatAverage(SampleFrame);
if (SampleMono != 0)
{
//修复：切断音
double percent = MathHelper.SegmentLine.SegmentsGraphic(EnvlopeLines, currentFrame);
SampleMono = (float)(SampleMono * (percent / 100.0));
}
//OverFloat
if (overlapFrames > 0)
{
float oldFrame = 0.0f;
if (ofh.Position < ofh.Length && ofh.Length > 0)
{
float[] oft = ofh.ReadNextSampleFrame();
oldFrame = oft[0];
OutputStream.Seek(-1 * fhelper.Samples2Bytes(1), SeekOrigin.Current);
overlapFrames--;
float a2 = fhelper.FramesMix(SampleMono, oldFrame);
float SampleMix = a2;
if (dropFrames > 0)
{
ofh.WriteSample(oldFrame);//放弃Seek
dropFrames--;
}
else
{
ofh.WriteSample(SampleMix);
}
}
else
{
if (dropFrames > 0)
{
dropFrames--;
}
else
{
ofh.WriteSample(SampleMono);
}
overlapFrames = 0;
}
}
else
{
if (dropFrames > 0)
{
dropFrames--;
}
else
{
ofh.WriteSample(SampleMono);
}
}
}
}
private static void Emu_Sf_Seek(WaveFileReader wfr, int SamplesNum, SeekOrigin seekOrigin)
{
wfr.Seek(SamplesNum * wfr.BlockAlign, seekOrigin);
}