private int OverlapSamples()
{
// window
var window = _mode.GetWindow(_prevFlag, _nextFlag);
// this is applied as part of the lapping operation
// now lap the data into the buffer...
var sizeW = _mode.BlockSize;
var right = sizeW;
var center = right >> 1;
var left = 0;
var begin = -center;
var end = center;
if (_mode.BlockFlag)
{
// if the flag is true, it's a long block
// if the flag is false, it's a short block
if (!_prevFlag)
{
// previous block was short
left = Block1Size / 4 - Block0Size / 4; // where to start in pcm[][]
center = left + Block0Size / 2; // adjust the center so we're correctly clearing the buffer...
begin = Block0Size / -2 - left; // where to start in _outputBuffer[,]
}
if (!_nextFlag)
{
// next block is short
right -= sizeW / 4 - Block0Size / 4;
end = sizeW / 4 + Block0Size / 4;
}
}
// short blocks don't need any adjustments
var idx = _outputBuffer.Length / _channels + begin;
for (var c = 0; c < _channels; c++)
{
_outputBuffer.Write(c, idx, left, center, right, _residue[c], window);
}
var newPrepLen = _outputBuffer.Length / _channels - end;
var samplesDecoded = newPrepLen - _preparedLength;
_preparedLength = newPrepLen;
return(samplesDecoded);
}
